Welcome to tech Stuff, a production from iHeartRadio. Hey there, and welcome to tech Stuff. I'm your host Jonathan Strickland. I'm an executive producer with iHeartRadio. And how the tech are you? It's time for another tech Stuff classic. This time we are concluding a discussion that we started last Friday with tech Stuff Goes Transmitter Hunting Part two. Joe McCormick joined me for this episode Joe as a host of Stuff to Blow your Mind, and we had a discussion about transmitter hunting that I hope you will find enjoyable. Take it away past Jonathan and Joe. So we need to move into more of a discussion about radio specifically, because even though radio is a subset of electromagnetic radiation, it covers an enormous range of frequencies and therefore.

Welcome to tech Stuff, a production from iHeartRadio. Hey there, and welcome to tech Stuff. I'm your host Jonathan Strickland. I'm an executive producer with iHeartRadio. And how the tech are you? It's time for another tech Stuff classic. This time we are concluding a discussion that we started last Friday with tech Stuff Goes Transmitter Hunting Part two. Joe McCormick joined me for this episode Joe as a host of Stuff to Blow your Mind, and we had a discussion about transmitter hunting that I hope you will find enjoyable. Take it away past Jonathan and Joe. So we need to move into more of a discussion about radio specifically, because even though radio is a subset of electromagnetic radiation, it covers an enormous range of frequencies and therefore.

And not all frequencies behave the same on Earth.

And not all frequencies behave the same on Earth.

True.

True.

Yeah, so you've got different bands you might have You've seen terms like HF or VHF, FEU HF. These are specific subbands of frequencies on the electromagnetic spectrum, all what we would call radio frequencies. But so yeah, you've got like high frequency, very high frequency, and a lot of what we're going to be talking about today is going to be in the VHF part of the spectrum.

Yeah, so you've got different bands you might have You've seen terms like HF or VHF, FEU HF. These are specific subbands of frequencies on the electromagnetic spectrum, all what we would call radio frequencies. But so yeah, you've got like high frequency, very high frequency, and a lot of what we're going to be talking about today is going to be in the VHF part of the spectrum.

Yeah, that very high frequency. So yeah, this radio spectrum is pretty broad and it goes well beyond the types of radio that the typical person can listen into, unless you happen to be one of those folks who you know, maybe you operate a maritime radio to help with navigation, in which case you are using frequencies most of us don't touch. But or maybe you are a doctor working with experimental medical imaging equipment, in which case you're using radio frequencies on the opposite end of the spectrum, because maritime radio uses very low frequency radio waves, whereas medical imaging uses extremely high frequency radio waves. So the range goes from the bottom is that like three herts, which means you get three waves passing a given point in a second, all the way up to tremendously high frequency, which is three thousand gigaherts or three trillion hurts, meaning three trillion waves pass a given point within a second. Actually, I like extremely low frequency more because the acronym is elf so elves. Elves communicate kind of like ense very long wave forms. The elves at the bottom of the ocean. Yeah, that's where we've stuck them. So again, you know, we talked about how all these waves are traveling at the speed of light, so it's really just the number of waves that pass a given point in a second that tells you a frequency, not speed of transmission, because that's going to remain the same no matter what. So a three hurts frequent and see wave will tell you that the wavelength for that particular wave has to be a one hundred thousand kilometers in length. That's a long radio wave, one hundred thousand kilometers. Meanwhile, and the opposite end of the spectrum, if you go all the way to that three thousand gigahertz wave, you're talking about one hundred micrometers in length. So teeny tiny micrometers are very tiny, huge difference obviously in the length of these waves. So that's why you know, the whole frequency wavelength relationship is important. So we use the different frequencies for very specific purposes. It's also important to point out that this is not universal. There are usually some sort of governing body within a country that designates what frequencies can be used for what purposes. In the US we have the FCC. So if you're looking at the terror hertz side of things, that's that ultra ultra high or terribly high frequency as is some sometimes referred to. It's for medical imaging, that kind of stuff, also molecular dynamics measurements, and other high tech information. The extremely low frequency would be like radio communication with submarines. Can't You can't use very high frequency when communicating with stuff that's underwater. The waves attenue are the radio waves get attenuated by the ocean water, and that creates problems with communication, But it's less of a problem with extremely low frequency and very long wavelength radio transmissions.

Yeah, that very high frequency. So yeah, this radio spectrum is pretty broad and it goes well beyond the types of radio that the typical person can listen into, unless you happen to be one of those folks who you know, maybe you operate a maritime radio to help with navigation, in which case you are using frequencies most of us don't touch. But or maybe you are a doctor working with experimental medical imaging equipment, in which case you're using radio frequencies on the opposite end of the spectrum, because maritime radio uses very low frequency radio waves, whereas medical imaging uses extremely high frequency radio waves. So the range goes from the bottom is that like three herts, which means you get three waves passing a given point in a second, all the way up to tremendously high frequency, which is three thousand gigaherts or three trillion hurts, meaning three trillion waves pass a given point within a second. Actually, I like extremely low frequency more because the acronym is elf so elves. Elves communicate kind of like ense very long wave forms. The elves at the bottom of the ocean. Yeah, that's where we've stuck them. So again, you know, we talked about how all these waves are traveling at the speed of light, so it's really just the number of waves that pass a given point in a second that tells you a frequency, not speed of transmission, because that's going to remain the same no matter what. So a three hurts frequent and see wave will tell you that the wavelength for that particular wave has to be a one hundred thousand kilometers in length. That's a long radio wave, one hundred thousand kilometers. Meanwhile, and the opposite end of the spectrum, if you go all the way to that three thousand gigahertz wave, you're talking about one hundred micrometers in length. So teeny tiny micrometers are very tiny, huge difference obviously in the length of these waves. So that's why you know, the whole frequency wavelength relationship is important. So we use the different frequencies for very specific purposes. It's also important to point out that this is not universal. There are usually some sort of governing body within a country that designates what frequencies can be used for what purposes. In the US we have the FCC. So if you're looking at the terror hertz side of things, that's that ultra ultra high or terribly high frequency as is some sometimes referred to. It's for medical imaging, that kind of stuff, also molecular dynamics measurements, and other high tech information. The extremely low frequency would be like radio communication with submarines. Can't You can't use very high frequency when communicating with stuff that's underwater. The waves attenue are the radio waves get attenuated by the ocean water, and that creates problems with communication, But it's less of a problem with extremely low frequency and very long wavelength radio transmissions.

Now, what about the kind of radio we think of as standard radio, as in radio accessible to the average consumer AM FM. That kind of stuff, so AM would be in the medium frequency. Medium frequency ranges from three hundred killer hertz to three thousand kill herts or three megaherts if you prefer AM radio specifically in the United States is in an even more narrow range than that, right, that's all of medium frequency AM radio in the US goes from five hundred third five killer hurts to one thousand, seven hundred killer hurts or one point seven mega hurts. If you wanted to talk about short wave radio, that's from five point nine mega hurts to twenty six point one mega hurts.

Now, what about the kind of radio we think of as standard radio, as in radio accessible to the average consumer AM FM. That kind of stuff, so AM would be in the medium frequency. Medium frequency ranges from three hundred killer hertz to three thousand kill herts or three megaherts if you prefer AM radio specifically in the United States is in an even more narrow range than that, right, that's all of medium frequency AM radio in the US goes from five hundred third five killer hurts to one thousand, seven hundred killer hurts or one point seven mega hurts. If you wanted to talk about short wave radio, that's from five point nine mega hurts to twenty six point one mega hurts.

CB goes to twenty six point ninety six mega hurts to twenty seven point four one mega hurts, and so on and so forth.

CB goes to twenty six point ninety six mega hurts to twenty seven point four one mega hurts, and so on and so forth.

So so FM radio is going to be that's mega hurts, right, So it's going to be around around one hundred mega.

So so FM radio is going to be that's mega hurts, right, So it's going to be around around one hundred mega.

Hurts, yes, exactly. So yeah, because power ninety nine, that would be at ninety nine mega hurts right, ninety nine point one I think originally maybe.

Hurts, yes, exactly. So yeah, because power ninety nine, that would be at ninety nine mega hurts right, ninety nine point one I think originally maybe.

Starts high eighties, I think, yeah, and.

Starts high eighties, I think, yeah, and.

Goes up to like one oh seven I think somewhere around there. So different countries have allocated their broad broadcast spectrum in different ways, so not everyone follows those exact same rules. There's usually some overlap. Now, when you know something about the wavelength of the radio frequency, that tells you what you need, how you need to build your antenna right, Because the length of your antenna is dependent upon the frequencies you're looking for. You want your antenna to be the right length to resonate properly with the radio frequencies you're searching for. There's no such thing as really a perfect universal antenna that can equally pick up all frequencies across the radio range. Now, you might wonder, how can you have like a pocket AM radio, because if AM radio is broadcasting in the medium frequency and has pretty long radio waves, and you need to have an antenna that is the right length to pick that up. Typically we're talking about half the length of the wavelength of the radio frequency you're looking at right, So if you're talking about like a wavelength that's one hundred meters long, then you're looking at a radio antenna that's between forty and fifty meters. How the heck do you fit that on like that? That seems ridiculous. Well, the antenna for AM radios are typical wire that are and that wire is wrapped around the core. Because it doesn't matter if the wire's straight or not straight or whatever, you can you can coil it inside a device and have it completely housed within the radio. So if you were to open up an AM radio, chances are you'd find a wire where one end is not attached to anything and it's just wrapped around around around around around a core of some sort. That's the antenna. It's it's not like it's providing any sort of electrical stimulation apart from convert you know, pulling in radio waves and having that induce an electric current. So that's why AM radios don't necessarily have a visible, incredibly long antenna. And this is important when it comes to things like transmitter hunting.

Goes up to like one oh seven I think somewhere around there. So different countries have allocated their broad broadcast spectrum in different ways, so not everyone follows those exact same rules. There's usually some overlap. Now, when you know something about the wavelength of the radio frequency, that tells you what you need, how you need to build your antenna right, Because the length of your antenna is dependent upon the frequencies you're looking for. You want your antenna to be the right length to resonate properly with the radio frequencies you're searching for. There's no such thing as really a perfect universal antenna that can equally pick up all frequencies across the radio range. Now, you might wonder, how can you have like a pocket AM radio, because if AM radio is broadcasting in the medium frequency and has pretty long radio waves, and you need to have an antenna that is the right length to pick that up. Typically we're talking about half the length of the wavelength of the radio frequency you're looking at right, So if you're talking about like a wavelength that's one hundred meters long, then you're looking at a radio antenna that's between forty and fifty meters. How the heck do you fit that on like that? That seems ridiculous. Well, the antenna for AM radios are typical wire that are and that wire is wrapped around the core. Because it doesn't matter if the wire's straight or not straight or whatever, you can you can coil it inside a device and have it completely housed within the radio. So if you were to open up an AM radio, chances are you'd find a wire where one end is not attached to anything and it's just wrapped around around around around around a core of some sort. That's the antenna. It's it's not like it's providing any sort of electrical stimulation apart from convert you know, pulling in radio waves and having that induce an electric current. So that's why AM radios don't necessarily have a visible, incredibly long antenna. And this is important when it comes to things like transmitter hunting.

Yeah, because if you look at transmitter hunting sites and we'll get into the specifics of the sport here in a minute, you see a lot of jargon that obviously has to do with stuff about like antenna length and frequencies and stuff like that. One of the common things you'll see is like the idea of a two meter hunt. Yes, the two meter arena is often considered the sweet spot for transmitter hunting. Now what does that mean When a HAM radio enthusiast talks about two meters.

Yeah, because if you look at transmitter hunting sites and we'll get into the specifics of the sport here in a minute, you see a lot of jargon that obviously has to do with stuff about like antenna length and frequencies and stuff like that. One of the common things you'll see is like the idea of a two meter hunt. Yes, the two meter arena is often considered the sweet spot for transmitter hunting. Now what does that mean When a HAM radio enthusiast talks about two meters.

They're telling you specifically about the size of the antenna that they are using. To two meters is a pretty decent sized antenna, right, like you know, a meter's like here in the United States, we don't necessarily think in terms of meters that frequently because we're not on the metric system. But yeah, that's the reason is because the frequencies that are being used by ham radio enthusiasts are falling in the VHF radio frequency band, that very high frequency. Now, that frequency band goes from thirty mega hurts to three hundred megaherts, and the radio wavelengths go from ten meters down to one meter. And we're using descending sizes because remember as frequency increases, the wavelength decreases, right, So if you're if you're hunting for a radio signal that's somewhere in that that four to five meter range, you need a two meter antenna in order to pick them up effectively to have it be particularly sensitive to those transmissions. Now, the specific range within VHF designated for amateur radio use is in the United States one hundred and forty four megahurts tow one hundred and forty eight megahertz. It's a little different in Europe where it's one forty four to one forty six.

They're telling you specifically about the size of the antenna that they are using. To two meters is a pretty decent sized antenna, right, like you know, a meter's like here in the United States, we don't necessarily think in terms of meters that frequently because we're not on the metric system. But yeah, that's the reason is because the frequencies that are being used by ham radio enthusiasts are falling in the VHF radio frequency band, that very high frequency. Now, that frequency band goes from thirty mega hurts to three hundred megaherts, and the radio wavelengths go from ten meters down to one meter. And we're using descending sizes because remember as frequency increases, the wavelength decreases, right, So if you're if you're hunting for a radio signal that's somewhere in that that four to five meter range, you need a two meter antenna in order to pick them up effectively to have it be particularly sensitive to those transmissions. Now, the specific range within VHF designated for amateur radio use is in the United States one hundred and forty four megahurts tow one hundred and forty eight megahertz. It's a little different in Europe where it's one forty four to one forty six.

So stingy with it over there and not quite as wide a range. Give us our two megaherts come on, yeah.

So stingy with it over there and not quite as wide a range. Give us our two megaherts come on, yeah.

And well, to be fair though, it's not the only band for amateur radio. Amateur radio actually has bands and several different frequency ranges. It's just for the VHF frequency range. It's this specific UH range of frequencies from eight in the US one forty four to one forty six in Europe. But you can also find amateur radio frequency bands in low, medium, and high frequency as well as all the way up to like terribly fast, terribly high frequency. You can find them up there too. Now, because of the wavelengths involved, that two meter antenna is best able to pick up those transmissions because it resonates more readily with transmissions in that frequency. Yeah, like it can pick up stuff outside of it, but not as effectively as the stuff it was designed for. It's that's the sweet spot. So you can build your own if you wanted to. There are a lot of different resources, both online and in libraries that will teach you how to build an antenna. I watched one that actually was so cool that I think I might do it as a project here at how stuff works and do a video about it. What kind of antenna was it would be? It would be a quad antenna. I'll talk about a little bit a little bit later.

And well, to be fair though, it's not the only band for amateur radio. Amateur radio actually has bands and several different frequency ranges. It's just for the VHF frequency range. It's this specific UH range of frequencies from eight in the US one forty four to one forty six in Europe. But you can also find amateur radio frequency bands in low, medium, and high frequency as well as all the way up to like terribly fast, terribly high frequency. You can find them up there too. Now, because of the wavelengths involved, that two meter antenna is best able to pick up those transmissions because it resonates more readily with transmissions in that frequency. Yeah, like it can pick up stuff outside of it, but not as effectively as the stuff it was designed for. It's that's the sweet spot. So you can build your own if you wanted to. There are a lot of different resources, both online and in libraries that will teach you how to build an antenna. I watched one that actually was so cool that I think I might do it as a project here at how stuff works and do a video about it. What kind of antenna was it would be? It would be a quad antenna. I'll talk about a little bit a little bit later.

Mostly guys, now, I've been thinking about trying to build a yacky antenna.

Mostly guys, now, I've been thinking about trying to build a yacky antenna.

Yeah, well, that would be great, both of them.

Yeah, well, that would be great, both of them.

As some of the Hams pronounce it, yaggy yaggy.

As some of the Hams pronounce it, yaggy yaggy.

Yeah, I think that that project would be really kind of fun. And also I like the way a quad antenna can look. I'll talk more about that in a little bit.

Yeah, I think that that project would be really kind of fun. And also I like the way a quad antenna can look. I'll talk more about that in a little bit.

Anyway, Well, well, I challenge you to an antenna built off.

Anyway, Well, well, I challenge you to an antenna built off.

That sounds great. Yeah, let's do it. Totally do it. To be fair, it's way easier to do it now than it was in the old hobbyist days, where you had to do all the calculations by hand. Now there are so many online tools that will allow you to just plug in what you're an attempting to do, and they'll tell you exactly how long each element.

That sounds great. Yeah, let's do it. Totally do it. To be fair, it's way easier to do it now than it was in the old hobbyist days, where you had to do all the calculations by hand. Now there are so many online tools that will allow you to just plug in what you're an attempting to do, and they'll tell you exactly how long each element.

I've been to exactly one of these calculators. I found one online that says like, Okay, here's the frequency I want to look for, here's the decibel gain I want. Yeah, and then it'll tell you the relative size of your of your elements for your antenna.

I've been to exactly one of these calculators. I found one online that says like, Okay, here's the frequency I want to look for, here's the decibel gain I want. Yeah, and then it'll tell you the relative size of your of your elements for your antenna.

Yeah. So, if you are a transmitter hunter, chances are you have multiple antenna or as I put, a veritable array of antenna, oh, perhaps a literal arrayna's, depending upon what you're depending upon how much money and time you have to put into the hobby.

Yeah. So, if you are a transmitter hunter, chances are you have multiple antenna or as I put, a veritable array of antenna, oh, perhaps a literal arrayna's, depending upon what you're depending upon how much money and time you have to put into the hobby.

Uh.

Uh.

But then we also have another element that you put in our notes. Yeah, they're a question. Yeah.

But then we also have another element that you put in our notes. Yeah, they're a question. Yeah.

So sometimes you'll hear or you'll read about people in the transmitter hunting community talking about harmonics. Yeah, you know, so they'll say, maybe, oh, I got very close to the transmitter and I was I was overwhelmed.

So sometimes you'll hear or you'll read about people in the transmitter hunting community talking about harmonics. Yeah, you know, so they'll say, maybe, oh, I got very close to the transmitter and I was I was overwhelmed.

What could I do?

What could I do?

You know, I suddenly I couldn't isolate the direction of the signal anymore. And somebody else might say, well, try looking for the third harmonic. I love that because it sounds very cryptic and in the know.

You know, I suddenly I couldn't isolate the direction of the signal anymore. And somebody else might say, well, try looking for the third harmonic. I love that because it sounds very cryptic and in the know.

Yeah, sounds a little Star Trek esque in a way. So harmonics are integer multiples of the fundamental frequency, which is a fancy way of saying you start with whatever frequency you're looking for, because generally speaking, transmitter hunters there's a specific frequency that they know they are searching for, Otherwise it would be needle in a haystack. Right. Plus they're limited anyway by the range that amateur operators are allowed to use. So you start with whatever the target frequency is and you multiply it by integers in order to get the harmonics. So the first harmonic is the fundamental frequency, because you just multiply by one, got it. So, third harmonic you multiply by three. Fifth harmonic you multiply by five. Both of those are particularly useful in transmitter hunting. So the typical frequency you'd be hunting for is one forty six point five six y five mega hurts. Now, if you want to find the third harmonic, you multiply that number by three. That gives you four hundred thirty nine points six ninety five megahurts. The fifth harmonic you multiply by five. That gives you seven hundred and thirty two point eight two five megahertz. Now, each of those harmonics has a weaker signal than the fundamental frequency.

Yeah, sounds a little Star Trek esque in a way. So harmonics are integer multiples of the fundamental frequency, which is a fancy way of saying you start with whatever frequency you're looking for, because generally speaking, transmitter hunters there's a specific frequency that they know they are searching for, Otherwise it would be needle in a haystack. Right. Plus they're limited anyway by the range that amateur operators are allowed to use. So you start with whatever the target frequency is and you multiply it by integers in order to get the harmonics. So the first harmonic is the fundamental frequency, because you just multiply by one, got it. So, third harmonic you multiply by three. Fifth harmonic you multiply by five. Both of those are particularly useful in transmitter hunting. So the typical frequency you'd be hunting for is one forty six point five six y five mega hurts. Now, if you want to find the third harmonic, you multiply that number by three. That gives you four hundred thirty nine points six ninety five megahurts. The fifth harmonic you multiply by five. That gives you seven hundred and thirty two point eight two five megahertz. Now, each of those harmonics has a weaker signal than the fundamental frequency.

But it would be related to the fundamental.

But it would be related to the fundamental.

Three related to it. But it is a weaker signal. Now, if you're when you get close to one of these transmitters, chances are the signal strength is such that you are it's hard for you to get any useful information.

Three related to it. But it is a weaker signal. Now, if you're when you get close to one of these transmitters, chances are the signal strength is such that you are it's hard for you to get any useful information.

Yeah, right, Like, say you might if you have a directional antenna, which we'll talk about in a minute. Yeah, you might be sweeping it all around and you're just maxing out your receiver no matter what direction you pointed in, right, because.

Yeah, right, Like, say you might if you have a directional antenna, which we'll talk about in a minute. Yeah, you might be sweeping it all around and you're just maxing out your receiver no matter what direction you pointed in, right, because.

The signal it's not like you're right on top of the transmitter, but you're close enough where the directionality is no longer useful. It's kind of like you can hear someone yelling off in the distance and you're blindfolded, so you know generally what direction they're in, but as you get really close and they're yelling and it's an echoe area, you can't really tell where the noise is coming from necessarily. It's kind of like that as an analogy. So if you're able to switch to one of these harmonics because it's a weaker signal, you can get a little more precise with that directionality. You can use it. If you have an antenna that can switch to one of these signals, or you have an antenna specifically made to detect those harmonics, then you are able to switch to a weaker signal which is not going to overwhelm your antenna so quickly, and you can hone in on the direction a little more precisely than you would if you had to rely on your chief two meter antenna.

The signal it's not like you're right on top of the transmitter, but you're close enough where the directionality is no longer useful. It's kind of like you can hear someone yelling off in the distance and you're blindfolded, so you know generally what direction they're in, but as you get really close and they're yelling and it's an echoe area, you can't really tell where the noise is coming from necessarily. It's kind of like that as an analogy. So if you're able to switch to one of these harmonics because it's a weaker signal, you can get a little more precise with that directionality. You can use it. If you have an antenna that can switch to one of these signals, or you have an antenna specifically made to detect those harmonics, then you are able to switch to a weaker signal which is not going to overwhelm your antenna so quickly, and you can hone in on the direction a little more precisely than you would if you had to rely on your chief two meter antenna.

Right.

Right.

Yeah, So that's why harmonics are important. Uh, and we'll talk a little bit more about the Yaggi antennas in a second. Yagi antenna more formally is the yagi Uda antenna, which sounds like it should be a Star Wars character, right, yagi Uda? Oh you seek yagy udah. Yeah, it's a directional antenna that looks kind of like one of those old TV antennas, like the old aerols that you would see on top of houses, typically in the movie like Willy Wonka and the Chocolate Factory.

Yeah, So that's why harmonics are important. Uh, and we'll talk a little bit more about the Yaggi antennas in a second. Yagi antenna more formally is the yagi Uda antenna, which sounds like it should be a Star Wars character, right, yagi Uda? Oh you seek yagy udah. Yeah, it's a directional antenna that looks kind of like one of those old TV antennas, like the old aerols that you would see on top of houses, typically in the movie like Willy Wonka and the Chocolate Factory.

Yeah, it has it has one long boom in the middle as well. Yeah, to a central pole on which are mounted parallel elements. And these elements are what does the shaping and receiving of the signal or transmitting. You can have a transmitter or receiver.

Yeah, it has it has one long boom in the middle as well. Yeah, to a central pole on which are mounted parallel elements. And these elements are what does the shaping and receiving of the signal or transmitting. You can have a transmitter or receiver.

Sure, yeah, antenna they're meant to be both transmitters and receivers, right. Typically the antenna that I use and most people use, I would imagine are simply used as receivers, except when you get into things like phones and stuff. Obviously, any phone type device has both a transmitter and receiver. Otherwise it's just a radio, so not terribly useful if you want to make a call, not that anyone does anymore, but I digress.

Sure, yeah, antenna they're meant to be both transmitters and receivers, right. Typically the antenna that I use and most people use, I would imagine are simply used as receivers, except when you get into things like phones and stuff. Obviously, any phone type device has both a transmitter and receiver. Otherwise it's just a radio, so not terribly useful if you want to make a call, not that anyone does anymore, but I digress.

Well, anyway, we'll talk about the specific centementute. But the point of these parallel elements on the Agie antenna is to create this directional effect. Yes, where a signal is detected if you are pointing right at it, but it is killed if you are pointing perpendicular to it right right.

Well, anyway, we'll talk about the specific centementute. But the point of these parallel elements on the Agie antenna is to create this directional effect. Yes, where a signal is detected if you are pointing right at it, but it is killed if you are pointing perpendicular to it right right.

So the idea being that if you turn to your right and the signal suddenly drops out, you know that the the direction to the right is not the way to go. You start turning to the left and you find where the signal drops out, you can eliminate that. It narrows down the range where the transmission can actually originate. And since transmitter hunting is all about finding that transmitter, that's important. And we're going to talk more about transmitter hunting and really dive into the hobby and the sport in just a moment, But first let's take another quick break to thank our sponsor. All Right, we're back, and Joe, I want you to tell me more about this sport of transmitter hunting, a sport I did not know existed until you brought this topic to my attention.

So the idea being that if you turn to your right and the signal suddenly drops out, you know that the the direction to the right is not the way to go. You start turning to the left and you find where the signal drops out, you can eliminate that. It narrows down the range where the transmission can actually originate. And since transmitter hunting is all about finding that transmitter, that's important. And we're going to talk more about transmitter hunting and really dive into the hobby and the sport in just a moment, But first let's take another quick break to thank our sponsor. All Right, we're back, and Joe, I want you to tell me more about this sport of transmitter hunting, a sport I did not know existed until you brought this topic to my attention.

Yeah, so I at some point want to try this. I've never done it myself, but I've been reading about it over the past couple months, and I've watched a few videos of people trying it out on YouTube and it looks very interesting. So the sport is known as transmitter hunting, also t hunting or fox hunting, and a standard game goes like this. You got one participant who is the hider. This is sort of the dungeon master of the fox hunt. Gotcha, and the hider puts together a radio transmitter appropriate for the scale of the hunt. So you might use a small handheld transmitter stashed inside an old ammunition can for a small scale hunt on foot or in a small several mile area with cars. And in this scenario, you would set the transmitter to repeat a signal at steady intervals, so it might be like.

Yeah, so I at some point want to try this. I've never done it myself, but I've been reading about it over the past couple months, and I've watched a few videos of people trying it out on YouTube and it looks very interesting. So the sport is known as transmitter hunting, also t hunting or fox hunting, and a standard game goes like this. You got one participant who is the hider. This is sort of the dungeon master of the fox hunt. Gotcha, and the hider puts together a radio transmitter appropriate for the scale of the hunt. So you might use a small handheld transmitter stashed inside an old ammunition can for a small scale hunt on foot or in a small several mile area with cars. And in this scenario, you would set the transmitter to repeat a signal at steady intervals, so it might be like.

Bpity beep beep beep, bpit beep, beep beep, gotcha.

Bpity beep beep beep, bpit beep, beep beep, gotcha.

And then you'd hide it somewhere, maybe in a public park or another a reasonably small search area. For large scale hunts, you could actually build a powerful antenna capable of transmitting miles and miles across state lines. There are people who do this in you know, these long all day car hunts. Where they're going a really long way to try to find a transmitter somewhere out in the desert or something. It looks like a lot of fun and you use it. You hunt it using cars or maybe fan boats. Wow, you know, so.

And then you'd hide it somewhere, maybe in a public park or another a reasonably small search area. For large scale hunts, you could actually build a powerful antenna capable of transmitting miles and miles across state lines. There are people who do this in you know, these long all day car hunts. Where they're going a really long way to try to find a transmitter somewhere out in the desert or something. It looks like a lot of fun and you use it. You hunt it using cars or maybe fan boats. Wow, you know, so.

You can you can do this in the Everglades. I would That's just the way I would like to do it. Yeah, I just all I can imagine is now we talked earlier about possibly making a movie. This movie would now have to star Burt Reynolds.

You can you can do this in the Everglades. I would That's just the way I would like to do it. Yeah, I just all I can imagine is now we talked earlier about possibly making a movie. This movie would now have to star Burt Reynolds.

But if you are hiding a transmitter, there are some social and safety concerns you probably want to keep in mind.

But if you are hiding a transmitter, there are some social and safety concerns you probably want to keep in mind.

Makes sense.

Makes sense.

Imagine, for example, you are out at a public park with your children and you see some creepy loaner with an antenna attached to their van pull up beside the park and then put a bunch of electronics inside an ammunition can and hide it in the bushes next to the sandbox.

Imagine, for example, you are out at a public park with your children and you see some creepy loaner with an antenna attached to their van pull up beside the park and then put a bunch of electronics inside an ammunition can and hide it in the bushes next to the sandbox.

I would say that that would raise at least one, possibly two red flags.

I would say that that would raise at least one, possibly two red flags.

Right, So you probably first of all, need to be careful where you hide your transmitters. You need to if it's you know, in a place where you would need permission, get permission first. In any case, if you're doing transmitter hunting, I've heard that it is a good idea to notify the police ahead of time that there are going to be people running around with antenna's and that you're going to be hiding a thing and let the police know where you're hiding it so that it doesn't get mistaken for a bomb or some other nefarious device. Yeah, it also looks like it's a good idea to put some writing on the device warning people that it's not dangerous.

Right, So you probably first of all, need to be careful where you hide your transmitters. You need to if it's you know, in a place where you would need permission, get permission first. In any case, if you're doing transmitter hunting, I've heard that it is a good idea to notify the police ahead of time that there are going to be people running around with antenna's and that you're going to be hiding a thing and let the police know where you're hiding it so that it doesn't get mistaken for a bomb or some other nefarious device. Yeah, it also looks like it's a good idea to put some writing on the device warning people that it's not dangerous.

Right, although honestly you wouldn't believe it. Yeah, I mean, I like if I were if I were the type to make a device that was intended to be harmful to people, I can't imagine that I would have the ethics to avoid writing this totally will not harm you.

Right, although honestly you wouldn't believe it. Yeah, I mean, I like if I were if I were the type to make a device that was intended to be harmful to people, I can't imagine that I would have the ethics to avoid writing this totally will not harm you.

It's like, I'm pretty sure a box of hot pocket says this is not.

It's like, I'm pretty sure a box of hot pocket says this is not.

Dangerous on it. Yeah, I mean it, but it was trust them, but definitely go to that extra effort. Yeah, we were talking offline about this before we came in here to record the episode, and the world is a very different place than what it was when. Uh. Transmitter hunting was really one of those hobbies that that people could essentially go anywhere and play. No one really noticed because they didn't even It was just be beneath the public consciousness. Joe found a book and lent it to me that I got to read, and in it they describe a situation where one person who was hiding a transmitter didn't have the time to actually do it himself, and so entrusted the transmitter to two other people who said, oh, yeah, we'll totally hide it where you told us, and instead they went and hit it under an overpass. And I thought those days are over. You would get into so much trouble now because you.

Dangerous on it. Yeah, I mean it, but it was trust them, but definitely go to that extra effort. Yeah, we were talking offline about this before we came in here to record the episode, and the world is a very different place than what it was when. Uh. Transmitter hunting was really one of those hobbies that that people could essentially go anywhere and play. No one really noticed because they didn't even It was just be beneath the public consciousness. Joe found a book and lent it to me that I got to read, and in it they describe a situation where one person who was hiding a transmitter didn't have the time to actually do it himself, and so entrusted the transmitter to two other people who said, oh, yeah, we'll totally hide it where you told us, and instead they went and hit it under an overpass. And I thought those days are over. You would get into so much trouble now because you.

Rememberary prank back then now freaks people out.

Rememberary prank back then now freaks people out.

Yeah, you remember the Moononites. Those are characters from Aquitine Hunger Force, where they Cartoon Network had done this promotional stunt where they put very simple led displays of the Moononites over certain bridges and it freaked people out. They thought perhaps it was like a weird warning about an explosive that had been attached to said overpasses. Turned out, of course, no, it was just a promotional stunt, but no one knew that at the time, and in the world that we live in today, it's probably better to take those extra precautions and to let whatever authority oversees the area that you're planting the transmitter in to know about it ahead of time, get approval, that kind of thing, and take these extra steps to make sure you don't inside a panic.

Yeah, you remember the Moononites. Those are characters from Aquitine Hunger Force, where they Cartoon Network had done this promotional stunt where they put very simple led displays of the Moononites over certain bridges and it freaked people out. They thought perhaps it was like a weird warning about an explosive that had been attached to said overpasses. Turned out, of course, no, it was just a promotional stunt, but no one knew that at the time, and in the world that we live in today, it's probably better to take those extra precautions and to let whatever authority oversees the area that you're planting the transmitter in to know about it ahead of time, get approval, that kind of thing, and take these extra steps to make sure you don't inside a panic.

By the way, you mentioned this book, and I just wanted to throw out the name of it, sure, because I was looking at this too.

By the way, you mentioned this book, and I just wanted to throw out the name of it, sure, because I was looking at this too.

It's a book I order.

It's a book I order.

Called Transmitter Hunting Radio Direction find being simplified. It's from the late nineteen eighties and it is a radio hobbyist manual by Joseph Moell and Thomas in Curly.

Called Transmitter Hunting Radio Direction find being simplified. It's from the late nineteen eighties and it is a radio hobbyist manual by Joseph Moell and Thomas in Curly.

An exhaustive hobbyist manual.

An exhaustive hobbyist manual.

Well, they've got a lot of projects and stuff back then for building different antenna types, but also just sort of an overview of what the sport looks like, you know, when people practice it. Sure, so when you get into a transmitter hunt, you've got the transmitter hidden somewhere, yeah, and you've got some boundaries established, and then the players.

Well, they've got a lot of projects and stuff back then for building different antenna types, but also just sort of an overview of what the sport looks like, you know, when people practice it. Sure, so when you get into a transmitter hunt, you've got the transmitter hidden somewhere, yeah, and you've got some boundaries established, and then the players.

Are set loose.

Are set loose.

They're like the dogs on a fox hunt, which I assume is where the name comes from and not some other counterintuitive naming scheme. But they know what to listen for, so they've got the frequency established, they know what the signal is, but they've got to somehow find the physical location of the transmitter.

They're like the dogs on a fox hunt, which I assume is where the name comes from and not some other counterintuitive naming scheme. But they know what to listen for, so they've got the frequency established, they know what the signal is, but they've got to somehow find the physical location of the transmitter.

Yep.

Yep.

Now, once you think you have isolated the direction from which a signal is coming, and in just a second, we'll talk about ways you could do that, some different equipment you could have. Typically you'll have some kind of antenna or device that gets you a bearing, so you've got a line to where you think the signal is coming from, and then from there there are a couple of primary ways you can hunt. One is the simple way, which is just chasing the bearing. Even this is not as simple as it sounds.

Now, once you think you have isolated the direction from which a signal is coming, and in just a second, we'll talk about ways you could do that, some different equipment you could have. Typically you'll have some kind of antenna or device that gets you a bearing, so you've got a line to where you think the signal is coming from, and then from there there are a couple of primary ways you can hunt. One is the simple way, which is just chasing the bearing. Even this is not as simple as it sounds.

Idea is that you found you've found a direction, and you're like, okay, well the transmission is coming from the southeast, so let's just get in the car and travel as close to southeast as we possibly can for a while, and then we'll jump out and check again.

Idea is that you found you've found a direction, and you're like, okay, well the transmission is coming from the southeast, so let's just get in the car and travel as close to southeast as we possibly can for a while, and then we'll jump out and check again.

Yeah, so you just follow it and then keep checking the signal. The other way would be what's known as triangulation. And so there imagine you would need a map.

Yeah, so you just follow it and then keep checking the signal. The other way would be what's known as triangulation. And so there imagine you would need a map.

For this, Yes, an actual physical paper map would probably.

For this, Yes, an actual physical paper map would probably.

You're going to make marks on as accurate distances and measurements. So you get a bearing from one known location. You know where you are, You mark your location on the map and then you get a bearing. So you draw a line on the map, saying, okay, it's coming from this direction. Then you go to another place on the map and you mark your location there and you get a bearing again. You say, okay, it's coming from this direction. Draw another line. Then you go to a third place, get a bearing again, and maybe do that another time. So, if everything is working correctly, those three or more lines should begin to intersect right the location of the transmitter.

You're going to make marks on as accurate distances and measurements. So you get a bearing from one known location. You know where you are, You mark your location on the map and then you get a bearing. So you draw a line on the map, saying, okay, it's coming from this direction. Then you go to another place on the map and you mark your location there and you get a bearing again. You say, okay, it's coming from this direction. Draw another line. Then you go to a third place, get a bearing again, and maybe do that another time. So, if everything is working correctly, those three or more lines should begin to intersect right the location of the transmitter.

There should be a convergence around the general area. Now, it may be because of geography and buildings and such that the signal you're picking up is a reflected signal and not really indicative of the actual source of transmission. Right Like, let's say that the source of the transmission is off by a few degrees from where you get your bearing because of this reflection. Well, as you do your triangulation, you might notice that that this intersection is a little weird, like, not all the it's not like all the lines are converging on a single point. It might be that they create a trapezoid of possible, and then the idea is that, all right, well, now we're going to need to get further closer to that trapezoid because we know that the transmitter is most likely within that area somewhere, but we have to narrow it down from there.

There should be a convergence around the general area. Now, it may be because of geography and buildings and such that the signal you're picking up is a reflected signal and not really indicative of the actual source of transmission. Right Like, let's say that the source of the transmission is off by a few degrees from where you get your bearing because of this reflection. Well, as you do your triangulation, you might notice that that this intersection is a little weird, like, not all the it's not like all the lines are converging on a single point. It might be that they create a trapezoid of possible, and then the idea is that, all right, well, now we're going to need to get further closer to that trapezoid because we know that the transmitter is most likely within that area somewhere, but we have to narrow it down from there.

Either way you go, if you're just homing in on a bearing or if you're trying to do triangulation, it's not as easy as it sounds, because, as you alluded to, the propagation of radio waves can be affected by all kinds of stuff, many variables like terrain, presence of water, reflective obstacles like fences, power lines, or even concrete buildings. So a hill can block your line of sight to a transmitter. Yeah, so the hill, a hill can be in the way. You might jump out of.

Either way you go, if you're just homing in on a bearing or if you're trying to do triangulation, it's not as easy as it sounds, because, as you alluded to, the propagation of radio waves can be affected by all kinds of stuff, many variables like terrain, presence of water, reflective obstacles like fences, power lines, or even concrete buildings. So a hill can block your line of sight to a transmitter. Yeah, so the hill, a hill can be in the way. You might jump out of.

Your vehicle and you're trying to pick up the signal and you can't pick up anything or whatever. You pay so a week that you can't really get a reading on where it's coming from, and instead of freaking out, it just may mean that you have to travel a little bit further to get the hill out of the way.

Your vehicle and you're trying to pick up the signal and you can't pick up anything or whatever. You pay so a week that you can't really get a reading on where it's coming from, and instead of freaking out, it just may mean that you have to travel a little bit further to get the hill out of the way.

Also, apparently, sometimes water and shorelines can change the apparent direction from which a signal is coming. So if the signals coming at you over water and then there's a shoreline, it can sort of shear the direction of it. There are some obviously, things like metal fences, power lines, buildings can create these reflective surfaces that will bounce the signal around. Some environments, like cities are absolutely jammed with radio reflective objects. So if you're in a city, the very buildings around you are just like bouncing the signal back and forth like a pinball, and this can create what's known as a multipath environment. So multipath is going to be one of the biggest problems to overcome if you are looking for a hidden transmitter, especially in a city or other area crowded with reflective obstacles, and it just means that you're getting the signal, you're tracking from multiple different directions, and you've got to have some experience and knowledge of how exactly to work around problems like that. Yeah, so a good hunter needs to have experience and skill, but they also are going to need, not necessarily need, but it really helps to have some specialized equipment, including special antennas and receivers.

Also, apparently, sometimes water and shorelines can change the apparent direction from which a signal is coming. So if the signals coming at you over water and then there's a shoreline, it can sort of shear the direction of it. There are some obviously, things like metal fences, power lines, buildings can create these reflective surfaces that will bounce the signal around. Some environments, like cities are absolutely jammed with radio reflective objects. So if you're in a city, the very buildings around you are just like bouncing the signal back and forth like a pinball, and this can create what's known as a multipath environment. So multipath is going to be one of the biggest problems to overcome if you are looking for a hidden transmitter, especially in a city or other area crowded with reflective obstacles, and it just means that you're getting the signal, you're tracking from multiple different directions, and you've got to have some experience and knowledge of how exactly to work around problems like that. Yeah, so a good hunter needs to have experience and skill, but they also are going to need, not necessarily need, but it really helps to have some specialized equipment, including special antennas and receivers.

Now, as the authors of that book, Joe mentioned point out multiple times, and experienced and skillful hunter can use seemingly inferior equipment and still produce a better result than someone who has lots of money and has dropped it on a bunch of high tech equipment but has little to no experience actually using set equipment. So there is a lot of art to this. It's not just science. There's a bit where you know, knowing kind of having an intuition about how radio waves work and the geography that you are in, and kind of getting an idea of how that could be affecting what you are receiving. It might be way more helpful than just a high tech antenna that is the costs a lot of money.

Now, as the authors of that book, Joe mentioned point out multiple times, and experienced and skillful hunter can use seemingly inferior equipment and still produce a better result than someone who has lots of money and has dropped it on a bunch of high tech equipment but has little to no experience actually using set equipment. So there is a lot of art to this. It's not just science. There's a bit where you know, knowing kind of having an intuition about how radio waves work and the geography that you are in, and kind of getting an idea of how that could be affecting what you are receiving. It might be way more helpful than just a high tech antenna that is the costs a lot of money.

Yeah, I have read the authors of this book say, and it does seem true to me based also on other things I've read that one of the most important pieces of equipment in a transmitter hunt is a map. Yes, it's having a good map, especially like a topographical map that includes surface features and buildings.

Yeah, I have read the authors of this book say, and it does seem true to me based also on other things I've read that one of the most important pieces of equipment in a transmitter hunt is a map. Yes, it's having a good map, especially like a topographical map that includes surface features and buildings.

And they also say that, you know, it can become incredibly challenging because the game doesn't necessarily confine itself to the area of any given map, so you might need multiple maps and that also becomes a bit of a challenge because unless the maps are both produced at the same scale, you can't just overlay them, you know, and tape them together or whatever it may be. That it requires a lot of math on your part. Yeah, so that's a strike against it for me. Well, let's do a real brief overview of some of the main types of antennas you might encounter absolutely transmit on. So we've mentioned by name several times the yagi or yaggy antenna yep. So this is a directional antenna. There are a couple major kinds of directional antennas, but a directional antenna, as we've said, it is designed to isolate the directionality of the signals. So if you point it at a right angle to the signal, you shouldn't be getting much of anything. Right if you point it in the opposite direction, most of them should say you know nothing or not much. But if you finally find the direction of the signal, the strength of the signal that comes through the antenna two year receiver should spike yes, and so a yaggi antenna is made of a series of metal elements arranged in parallel. So if you're trying to picture this, think of one long pole could be like a broom handle or PBC pipe or whatever. And then there are metal rods or wires of very lengths, and the lengths are very specific and very important, yes, and they are determined by the frequency of the signal that you're looking for. The relationship of the links of the various elements are very important, depending upon what their job is. Yeah.

And they also say that, you know, it can become incredibly challenging because the game doesn't necessarily confine itself to the area of any given map, so you might need multiple maps and that also becomes a bit of a challenge because unless the maps are both produced at the same scale, you can't just overlay them, you know, and tape them together or whatever it may be. That it requires a lot of math on your part. Yeah, so that's a strike against it for me. Well, let's do a real brief overview of some of the main types of antennas you might encounter absolutely transmit on. So we've mentioned by name several times the yagi or yaggy antenna yep. So this is a directional antenna. There are a couple major kinds of directional antennas, but a directional antenna, as we've said, it is designed to isolate the directionality of the signals. So if you point it at a right angle to the signal, you shouldn't be getting much of anything. Right if you point it in the opposite direction, most of them should say you know nothing or not much. But if you finally find the direction of the signal, the strength of the signal that comes through the antenna two year receiver should spike yes, and so a yaggi antenna is made of a series of metal elements arranged in parallel. So if you're trying to picture this, think of one long pole could be like a broom handle or PBC pipe or whatever. And then there are metal rods or wires of very lengths, and the lengths are very specific and very important, yes, and they are determined by the frequency of the signal that you're looking for. The relationship of the links of the various elements are very important, depending upon what their job is. Yeah.

So there is the most important elements. The main one is the driven element, and this is the electrically active part. This is the one that connects to the wires that go down to your receiver handheld radio receiver. This is what is resonating with that frequency. But then there are these other elements that are known as the parasitic elements, and they're not connected to the receiver, but they're there to manipulate the types of waves that the driven element receives.

So there is the most important elements. The main one is the driven element, and this is the electrically active part. This is the one that connects to the wires that go down to your receiver handheld radio receiver. This is what is resonating with that frequency. But then there are these other elements that are known as the parasitic elements, and they're not connected to the receiver, but they're there to manipulate the types of waves that the driven element receives.

Yeah, this is what gives these directional antenna their directionality. Yeah.

Yeah, this is what gives these directional antenna their directionality. Yeah.

So there's a reflector element that goes behind the driven element. So if you're pointing at the signal source, the reflector element should be closer to you and behind the driven one, and it reflects the signal back and focuses the reception field to the direction that the antenna's pointing. And then there may be multiple director elements, which are more elements in parallel ahead of the active element to help manipulate the shape of the wave forms and enforce directionality.

So there's a reflector element that goes behind the driven element. So if you're pointing at the signal source, the reflector element should be closer to you and behind the driven one, and it reflects the signal back and focuses the reception field to the direction that the antenna's pointing. And then there may be multiple director elements, which are more elements in parallel ahead of the active element to help manipulate the shape of the wave forms and enforce directionality.

So if you're looking at these different elements, first of all, if you're trying to envision this in your head, imagine that broomstick, all right, the broomstick you are holding out from yourself. These elements are perpendicular to the broomstat stick, but parallel with each other, right, So at the closest end to you, you have this reflector element. It's going to be the largest of those elements. Then you have the just slightly not just slightly and not by a whole lot, and it sort of is acting kind of like the dish in a satellite dish antenna sort of in that same style. So it's it's slightly larger than the driven element. That's the one that you were you know, is actually hooked up to the sensor so that it's pulling in the signal. And then at the far end you have the director elements. These are the shortest of the elements. And again it's not dramatically shorter, it's just a little shorter. All of the size sizes of these depend upon the frequency you're searching for. I mean, if you want to build a yagi for a very specific purpose, you would look at the frequency you're looking for, and there's a mathematical formula you use that gives you the ideal driven element size, reflector elements size, and director element sizes, And it's essentially you take a number and you divide. Also also their distance from each other. That is also Yeah, the spacing is also important. The spacing between these elements is very important. You can't just put them anywhere along that broomstick. You need to have them spaced out properly. So both of the those things are very important in order for you to get an antenna that is going to resonate properly with the frequency you want and therefore help you narrow down its direction. Yeah.

So if you're looking at these different elements, first of all, if you're trying to envision this in your head, imagine that broomstick, all right, the broomstick you are holding out from yourself. These elements are perpendicular to the broomstat stick, but parallel with each other, right, So at the closest end to you, you have this reflector element. It's going to be the largest of those elements. Then you have the just slightly not just slightly and not by a whole lot, and it sort of is acting kind of like the dish in a satellite dish antenna sort of in that same style. So it's it's slightly larger than the driven element. That's the one that you were you know, is actually hooked up to the sensor so that it's pulling in the signal. And then at the far end you have the director elements. These are the shortest of the elements. And again it's not dramatically shorter, it's just a little shorter. All of the size sizes of these depend upon the frequency you're searching for. I mean, if you want to build a yagi for a very specific purpose, you would look at the frequency you're looking for, and there's a mathematical formula you use that gives you the ideal driven element size, reflector elements size, and director element sizes, And it's essentially you take a number and you divide. Also also their distance from each other. That is also Yeah, the spacing is also important. The spacing between these elements is very important. You can't just put them anywhere along that broomstick. You need to have them spaced out properly. So both of the those things are very important in order for you to get an antenna that is going to resonate properly with the frequency you want and therefore help you narrow down its direction. Yeah.

So then there's another very popular form of directional antenna that is accomplishes the same goal but with a different type of construction, and that's the quad antenna.

So then there's another very popular form of directional antenna that is accomplishes the same goal but with a different type of construction, and that's the quad antenna.

Yeah. They're also typically used to detect frequencies in the high frequency or very high frequency ranges. So they consist of the driven element and the direction and a reflective element or directive elements, I should say, just like the yagi is, but they're arranged in a slightly different way. They use loops of wire, these loops that are not necessarily in a circle, They just need to be closed off. So the example I saw was a cubicle two element quad antenna, and actually it's technically a three element, but because you've got the driven you've got the reflector, and the the direction one the directive element. I liked it because it kind of looks like a tie fighter.

Yeah. They're also typically used to detect frequencies in the high frequency or very high frequency ranges. So they consist of the driven element and the direction and a reflective element or directive elements, I should say, just like the yagi is, but they're arranged in a slightly different way. They use loops of wire, these loops that are not necessarily in a circle, They just need to be closed off. So the example I saw was a cubicle two element quad antenna, and actually it's technically a three element, but because you've got the driven you've got the reflector, and the the direction one the directive element. I liked it because it kind of looks like a tie fighter.

Oh yeah, they look like tie fighter wings the loops do.

Oh yeah, they look like tie fighter wings the loops do.

Yeah. Now that's just the cubicle version. There are other variants of the quad antenna. These are these are slightly different look, I mean, a very different look from the yagis. They have a very sensitive directionality to them, and they also tend to have a slightly higher gain than Yaggi's by about two decibels. Decibel is a sliding scale, by the way, it's a logarithmic scale, right, not so two decibels on its own means nothing. You need to have another point of reference for you to understand what.

Yeah. Now that's just the cubicle version. There are other variants of the quad antenna. These are these are slightly different look, I mean, a very different look from the yagis. They have a very sensitive directionality to them, and they also tend to have a slightly higher gain than Yaggi's by about two decibels. Decibel is a sliding scale, by the way, it's a logarithmic scale, right, not so two decibels on its own means nothing. You need to have another point of reference for you to understand what.

To decibles, but if you've got a weak signal and you need to amplify it, that could be important.

To decibles, but if you've got a weak signal and you need to amplify it, that could be important.

Yeah, So quad antennas are a popular way of trying to track down a signal, especially if you need a little bit more sensitivity than you would with a yagi. So both of these are popular. They also come in different sizes. I mean, obviously it depends upon what frequencies you're looking for. The quad antenna is interesting because the length of the loop is dependent upon the frequency you're you're searching for. So the squares in the tie fighter, like the wing size of the tie fighter, are dependent upon that frequency. And the reflector is actually going to be slightly larger than the other ones. So I was watching a video on how to make this, and that's when I said, I kind of want to make one of these. And you know, the mobile ones are slightly smaller than the ones you might mount at your house if you happen to live out in the country and you can have a forty meter tall antenna in your backyard. But they are and it definitely doesn't look like something that's easy to carry around. I mean, they're not, they're not small. A lot of people who are serious about this hobby they have.

Yeah, So quad antennas are a popular way of trying to track down a signal, especially if you need a little bit more sensitivity than you would with a yagi. So both of these are popular. They also come in different sizes. I mean, obviously it depends upon what frequencies you're looking for. The quad antenna is interesting because the length of the loop is dependent upon the frequency you're you're searching for. So the squares in the tie fighter, like the wing size of the tie fighter, are dependent upon that frequency. And the reflector is actually going to be slightly larger than the other ones. So I was watching a video on how to make this, and that's when I said, I kind of want to make one of these. And you know, the mobile ones are slightly smaller than the ones you might mount at your house if you happen to live out in the country and you can have a forty meter tall antenna in your backyard. But they are and it definitely doesn't look like something that's easy to carry around. I mean, they're not, they're not small. A lot of people who are serious about this hobby they have.

They have mounts attached to their cars.

They have mounts attached to their cars.

Yeah, yeah, so you'll see vans with the things attached or jeeps that kind of thing, with these things attached to the vehicles themselves mounted on them, and they're not meant to be taken off. So that's another popular one. Another one is the Doppler direction finder.

Yeah, yeah, so you'll see vans with the things attached or jeeps that kind of thing, with these things attached to the vehicles themselves mounted on them, and they're not meant to be taken off. So that's another popular one. Another one is the Doppler direction finder.

Now this is going to be somewhat different than the directional antennas. It still ultimately establishes directionality, but it makes use of the eponymous Doppler effect.

Now this is going to be somewhat different than the directional antennas. It still ultimately establishes directionality, but it makes use of the eponymous Doppler effect.

Yes, named after a Christian Doppler who was known for running down the hallways going e I got Dylan laughing on that one. Who's just so absurd that Dylan Stern laughing. It's rare that I get our producer to laugh at something, but that was one of them. No. So, Doppler was a nineteenth century physicist, apparently in my world, a slightly absurd one, and he came up with the equations to describe the apparent frequency shifts we perceive that happened from the relative motion of us center of a signal and the receiver of a signal or a wave. Now you've heard me talk about this before you probably experienced it. The easiest way to give an example is with sound waves. So if you've ever noticed a siren on an approaching emergency vehicle being much higher pitched than it is when it passes you, So it's coming at you, it's a higher pitch noise, it passes you, it's a lower pitch noise. Or if you happen to be next to it and the two of you are either motionless or you're moving at the same speed in the same direction, it may sound like a pitch that's somewhere in between. That's because of the Doppler shift. When the vehicles moving towards you, it is effectively compressing those sound waves. So it's increasing the frequency, which we perceive as an increase in making the pitch go up. When it's moving away from you, it's elongating those sound waves, and so our perception of that is that it's a lower frequency and the pitch goes down. Same sort of thing is true with electro magnetic radiation. Actually it's also true with light I mean, which technically is part of electromagnetic radiation, but it's not radio waves. The same thing is true for all of these things. Yeah, so you shift exactly. Yeah, it's how we measure how fast we're moving away from or toward other galaxies, for example. So using a very special type of antenna you can take advantage of this property of physics. So Toppler direction finders typically have several rotating elements and it's usually between three and eight vertically oriented antenna. The antenna pick up these signals that then are sent to a processor that determines where is the signal really coming from? The incoming signal, where is that coming from? And typically there's like a circular display that it's just a circle of led lights is the simplest version, and whatever direction the signal appears to be coming from with respect to the the front of your vehicle, a light will pop up. So it's not telling you that, oh, you need to go northeast. It'll tell you, oh, the signals coming this many degrees to your right, or this many degrees to your left, or it's actually coming from behind you. That kind of thing. So if you were driving due west and the signal at the three o'clock position or the light at the three o'clock position on your little circular display lights up, that would tell you that the signal is actually coming from the north. Yeah, because to your right would be true north if you're going due west. So you look at this signal the circle of lights, and whichever one is lit up, that's telling you, all right, well, we need to start changing our bearing toward that direction if we want to head in the direction of the transmission itself.

Yes, named after a Christian Doppler who was known for running down the hallways going e I got Dylan laughing on that one. Who's just so absurd that Dylan Stern laughing. It's rare that I get our producer to laugh at something, but that was one of them. No. So, Doppler was a nineteenth century physicist, apparently in my world, a slightly absurd one, and he came up with the equations to describe the apparent frequency shifts we perceive that happened from the relative motion of us center of a signal and the receiver of a signal or a wave. Now you've heard me talk about this before you probably experienced it. The easiest way to give an example is with sound waves. So if you've ever noticed a siren on an approaching emergency vehicle being much higher pitched than it is when it passes you, So it's coming at you, it's a higher pitch noise, it passes you, it's a lower pitch noise. Or if you happen to be next to it and the two of you are either motionless or you're moving at the same speed in the same direction, it may sound like a pitch that's somewhere in between. That's because of the Doppler shift. When the vehicles moving towards you, it is effectively compressing those sound waves. So it's increasing the frequency, which we perceive as an increase in making the pitch go up. When it's moving away from you, it's elongating those sound waves, and so our perception of that is that it's a lower frequency and the pitch goes down. Same sort of thing is true with electro magnetic radiation. Actually it's also true with light I mean, which technically is part of electromagnetic radiation, but it's not radio waves. The same thing is true for all of these things. Yeah, so you shift exactly. Yeah, it's how we measure how fast we're moving away from or toward other galaxies, for example. So using a very special type of antenna you can take advantage of this property of physics. So Toppler direction finders typically have several rotating elements and it's usually between three and eight vertically oriented antenna. The antenna pick up these signals that then are sent to a processor that determines where is the signal really coming from? The incoming signal, where is that coming from? And typically there's like a circular display that it's just a circle of led lights is the simplest version, and whatever direction the signal appears to be coming from with respect to the the front of your vehicle, a light will pop up. So it's not telling you that, oh, you need to go northeast. It'll tell you, oh, the signals coming this many degrees to your right, or this many degrees to your left, or it's actually coming from behind you. That kind of thing. So if you were driving due west and the signal at the three o'clock position or the light at the three o'clock position on your little circular display lights up, that would tell you that the signal is actually coming from the north. Yeah, because to your right would be true north if you're going due west. So you look at this signal the circle of lights, and whichever one is lit up, that's telling you, all right, well, we need to start changing our bearing toward that direction if we want to head in the direction of the transmission itself.

Now, another type of direction finder that you could use would be something that's known as a time difference of arrival antennas. Yeah, and this is another interesting thing. So it has multiple receips elements arranged in a pattern that passed the signal along to an electronic or computational core that compares the time delay between when the different elements received the same signal pattern.

Now, another type of direction finder that you could use would be something that's known as a time difference of arrival antennas. Yeah, and this is another interesting thing. So it has multiple receips elements arranged in a pattern that passed the signal along to an electronic or computational core that compares the time delay between when the different elements received the same signal pattern.

Now this is crazy because remember these signals travel at the speed of light, so the differences are not detectable by humans, right, Like, there's no way that we humans would be able to tell the difference.

Now this is crazy because remember these signals travel at the speed of light, so the differences are not detectable by humans, right, Like, there's no way that we humans would be able to tell the difference.

And this is obviously easier if you have, you know, something where there are multiple elements that are very.

And this is obviously easier if you have, you know, something where there are multiple elements that are very.

Far away from each other.

Far away from each other.

Absolutely installations, sure, sure, but yeah, so you can use time difference of arrival. Since we know the speed of radio transmission is constant. We know exactly what the speed is, and we know the difference between the different elements. We can use the time delay between when they receive the signal to calculate the direction the signals coming from.

Absolutely installations, sure, sure, but yeah, so you can use time difference of arrival. Since we know the speed of radio transmission is constant. We know exactly what the speed is, and we know the difference between the different elements. We can use the time delay between when they receive the signal to calculate the direction the signals coming from.

All right, So we've talked a lot about antennas and we've we've mentioned receiver quite a few times. Now. Some people listening maybe thinking that what you're doing is you got a pair of cans on your ears and you're listening really carefully for the beaty beeps. But as it turns out, most of the time, we're actually talking about a piece of equipment that indicates when it's receiving a signal and giving you an idea of how strong that signal is. Let's talk about that for a second.

All right, So we've talked a lot about antennas and we've we've mentioned receiver quite a few times. Now. Some people listening maybe thinking that what you're doing is you got a pair of cans on your ears and you're listening really carefully for the beaty beeps. But as it turns out, most of the time, we're actually talking about a piece of equipment that indicates when it's receiving a signal and giving you an idea of how strong that signal is. Let's talk about that for a second.

Well, so it is going to be a receiver, radio receiver, a radio receiver you might be familiar with, but the most useful ones obviously are going to be ones that are equipped with what's known as an S meter. So you've got your antenna and you've got a wire running from your antenna to the receiver or wires running from the antenna to the receiver, and the receiver should be able to translate the signal into something you can make sense of. That might be sounds, or that might be a number, and in the case of an S meter, it would be a number. It's a gauge that gives you a direct reading in a numerical value of the strength of the signal. So you're not just relying on you know, subjective impressions from listening or some other method, right, so you just find the direction where the number on the S meter is the highest.