Fm Radio Trick?

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Dispatrick

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i tried the trick were someone is listening to a FM radio station (example 105.9) and you take another FM radio and you tune 10.7 mhz above (116.6 mhz) or below (95.2 mhz) the station they are listening to and it will block the station they are listening to. i have tried this a thousand times and no successs does anyone know what im doing wrong?

thanks :)
 

n8emr

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As with most legends it has a basis in truth. With the older single conversion radio's you can do that. With newer modern radio it will not work.
 

ryangassxx

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i tried the trick were someone is listening to a FM radio station (example 105.9) and you take another FM radio and you tune 10.7 mhz above (116.6 mhz) or below (95.2 mhz) the station they are listening to and it will block the station they are listening to. i have tried this a thousand times and no successs does anyone know what im doing wrong?

thanks :)
There's 13 old ham radio farts reporting you to the FCC as we speak...
 

KC0QNB

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There's 13 old ham radio farts reporting you to the FCC as we speak...
So who do you consider an old ham radio fart, 10,20,30 years old or higher?
It appears you are not a ham, but that is ok we "old ham radio farts" are hams and are proud of it, we worked for it and earned it.
That being stated, I don't see why the FCC would care, if that 10.7 thing worked on modern equipment, the best he could do is jam the radio near the radio he is trying to jam the radio with to a point both radios wouldn't hear very good, we are talking just a few inches apart, no major problem for anyone else.
here is a trick that used to work, you are listening to a side band station on SW but since you don't have a sideband capable receiver, take another am type radio and tune til you can hear the sideband signal clearly, again the radio sets need to be fairly close together, try it some time let me know if it still works, as well as I remember after all I might be an old ham radio fart, and my memory isn't as good as it used to be.
73 KCØQNB
 

Austin4Wyo

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Think about it...
*sigh*

Think about what, precisely? I'm not familiar with FCC guidelines. Naturally occurring interference doesn't seem like something they'd be interested in, unless you could provide some sort of malicious use on a large enough scale to get their attention.

Someone care to fill in the un-initiated radio neophyte?
 
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KC0QNB

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Oops I forgot something very important, don't try what I mentioned with two synthesized receivers, one of them has to be a OLD FASHIONED varicap tuned unit, perhaps even both I did this trick many years ago, to listen to sideband.

I would guess he has heard that doing that kind of thing would cause major interference to station, I have never heard that one, so I am not an expert.
I see at least one problem about trying this, as I understand it, if you wanted to block the neighbors FM receiver one of the first things would be knowing what station the neighbor was listening to,
I could see the possibility of generating a strong enough signal with the combination of the IF and the receiver frequency allowing the user to hear a different signal altogether if one was present at the time, but I don't think it would create a problem with another receiver there fore the FCC wouldn't care.
I used to listen to a radio station on AM620 with a reel to reel tape recorder (just a tape recorder no radio combo unit), but you had to have the microphone stretched all the way out and horizontal. It worked great until the teacher caught me and told me to go back to study hall, cuz I was supposed to be practicing my trumpet, not listening to the radio.
 
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PhilJSmith67

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This trick used to work very well for me, affecting radios as far as 50' away, back when I lived 50+ miles from most "local" FM stations. And, of course, if I was using an analog radio with a strong local oscillator. You won't jam any relatively strong stations more than a couple feet away though. With today's digital receivers, it's a crap shoot if it will work at all.
 

rcvmo

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Easy boys, settle down now!!
Yes, I used to be able to tune Detroit police on the UHF channels back in the early 80's with an old channel selector type tv set and an old GE capacitive am/fm radio nearby. Not only just detroit, but the entire 400-500 MHz band altogether. And i'm an old ham radio fart too. Specifically an old fart like my wife all of 9 years together calls me. And what does the old ham radio fart do? Get respect for knowing what the heck is going on out in the world and the 'hood. Take for instance the graduation ceremony we went to tonight. Storms bearing down on the crowd, lives and livelyhood are at stake, and I with a small ham radio have the attention of the DHS/EMD coord, sheriff and local PD/FD attending because I have the connection beyond their normal communications. Was it fun tonight? You bet.
rcvmo
 

jon_k

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I'm 23 and I'm licensed as an amateur operator. We're not ALL old farts. In 50 years I'll be an old fart, but you will be too.

Back to topic of OP. Why did this USE to work on old receivers? Leaked harmonics from the VFO that interrupt the primary receiver?
 

zz0468

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i tried the trick were someone is listening to a FM radio station (example 105.9) and you take another FM radio and you tune 10.7 mhz above (116.6 mhz) or below (95.2 mhz) the station they are listening to and it will block the station they are listening to. i have tried this a thousand times and no successs does anyone know what im doing wrong?

thanks :)
It's possible that the fm station the user was listening to was just too strong to be captured by the LO from the other receiver. I've done that trick, and know it works, but it requires that the LO you're trying to hear be strong enough to capture the target receiver.
 

mancow

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Yo man..... it's just humor, that's all.



*sigh*

Think about what, precisely? I'm not familiar with FCC guidelines. Naturally occurring interference doesn't seem like something they'd be interested in, unless you could provide some sort of malicious use on a large enough scale to get their attention.

Someone care to fill in the un-initiated radio neophyte?
 

PhilJSmith67

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It's possible that the fm station the user was listening to was just too strong to be captured by the LO from the other receiver. I've done that trick, and know it works, but it requires that the LO you're trying to hear be strong enough to capture the target receiver.
Exactly... It doesn't work well if you're listening to a station where you're getting a strong, city-grade signal.

I had one of those older analog TV/FM receivers that tuned continuously from ch2 through ch6 and up through FM (54-108 MHz). That radio had a potent local oscillator (LO) which could interfere with a "fair strength" FM station from 30 or so feet away. Unlike FM radios that couldn't go below approximately 87 MHz (meaning they couldn't block anything below 98 FM), the TV/FM radio went clear down to 54 MHz, so it could throw a dead carrier on any FM frequency, or even TV channels 3 through 6. Believe me, in a short range, this was a very effective "jammer" radio.
 

ryangassxx

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Some of you guys seriously need to relax.. I didn't accuse everyone with a ticket of being an "old fart".. If you went out of your way to include yourself in that category, well then what can I say..

And it was obviously a joke to begin with.. This is one of the most dry forums ever... It really doesn't take a whole lot to rub everyone the wrong way..



And to the guy who doesn't understand why the FCC would frown upon someone intentionally and willfully jamming or interfering with the reception of someone else's receiver, why don't you take a look at the back of ANY consumer grade electronic device and read that little sticker.. But, really, isn't it just common sense? It doesn't take an old ham radio fart to know that it's never good to purposefully jam someone's radio..

Naturally occurring interference doesn't seem like something they'd be interested in, unless you could provide some sort of malicious use on a large enough scale to get their attention.
Well,... are you talking about naturally occurring interference, or using your radio to jam another radio? Yeah, I mean the FCC can't really do much about lightning storms, but who's talking about that? I think the question you meant to ask is, "Is it even realistic that I would get caught by the FCC doing this"? The answer is no, unless you go online and tell a bunch of old ham radio farts about it,.. Then you might get a nice letter from the FCC in your mail..
 
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zz0468

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I think the question you meant to ask is, "Is it even realistic that I would get caught by the FCC doing this"? The answer is no, unless you go online and tell a bunch of old ham radio farts about it,.. Then you might get a nice letter from the FCC in your mail..
I find it quite amusing that you're getting bent about the FCC, when you were the first one to mention it in this thread. The OP merely asked why the trick wasn't working for him. *eye roll*
 
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