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FM Wireless Microphone receiver Answered

About a year ago I got one end of an wireless microphone system at a yard sale. As far as I can tell, it is the sending unit. The recieving unit is lost to posterity, which is why it was so cheap, and has since been collecting dust. It has an RCA line in, 1/4 inch microphone in, a squelch knob, an output knob, a two-foot antenna, and a power button. It says it operates at 49.83MHz FM. I don't have a receiver that will pick up that frequency, and I'd like to know what it would take to build one. Perhaps mod an existing FM radio?


I think that the fm micraphone that you have works off of a fm receiver, you will have to turn the micraphone on and go to a blank channel on your fm receiver to find the correct channel, once you hear yourself broadcasting over the receiver .

. 49.83 MHZ is pretty common - walkie-talkies, baby monitors, &c. Look for something at the next yard sale. ;)

Ha, so my test to see if anything I owned would even react to my device probably had some parent wondering how their baby aquired a taste for Def Leppard? I'll have to keep that info in mind at the next yard sale.

> wondering how their baby aquired a taste for Def Leppard . ROFL

Really ? Channel 3 of the CB band used to be the ole walkie talkie channel, but I hadn't ever looked up the frequency. I will have to remember that.

Ok, maybe the newer walkie-talkies are of a different frequency then the one's I grew up with :-) I had one set that was Channel 3 or 4 switchable....wired the antenna up to our heating duct-work at home (I was in my teens then) and picked up a CB'er about a mile away (normal range was not further then 1/2 mile under the best of conditions :-)

88.1 - 108.1 is the range of the Normal FM broadcast band. If you are familiar with the inner workings of an FM radio, I would think that modification would be the easiest route. It may not be possible for some radios though. Note: if you tweak the radio, also consider tweaking the Antenna tuning if the radio has that also.

Unfortunately, I'm not familiar with FM at all. I've dabbled in AM, but I hear FM is a completely different animal. I have an FM radio that seems to have broken that I've been meaning to fix, and while I have it open, I might as well try and modify it to pick up a different range. It can't really get more broken. What, precisely, should I tweak?

What, precisely, should I tweak?

Uh, that is going to depend on the radio, it's age (which determines how it is made), and so on. Sorry I can't be more exacting, but there are so many different configurations out there...

Well, he knows the frequency of the transmitter, without a decent amount of equipment, it might be a little touch and go....but maybe I am just being too cautious ? :-)