nyet@nntp-server.caltech.edu (n liu) (05/02/91)
I was paging though Crutchfield the other day when i came upon a fm signal booster for ~30 bucks. Now, i thought to myself, I wouldn't mind trying one of those out, since my rather cheezy tuner don't lock into the stereo carrier too good. But I wasn't about to buy it, for several reasons.. One: catalog=drag Two: thirty bucks Three: my tuner might be beyond hope. So, hell, how hard could it be to just build one of these suckers? So what kind of components/gain/etc. should i be looking for? I've built minor audio amps, etc. but i'm not to familiar with the MHz range... Any recommendations? thanks nye
miker@polari.UUCP (Mike Ranta) (05/03/91)
>I was paging though Crutchfield the other day when i came >upon a fm signal booster for ~30 bucks. Now, i thought to >myself, I wouldn't mind trying one of those out, since >my rather cheezy tuner don't lock into the stereo carrier >too good. But I wasn't about to buy it, for several reasons.. FM signal boosters are basically worthless. Unless you have a _real_ cheap receiver _and_ live way out in the sticks, they only create more problems than they solve. For one thing, signal strength usually isn't the problem with FM reception. All that crap you hear as you drive around is usually multipath and is caused by reflections not by low signal (it does _appear_ that the signal is dropping in and out but it's actually being cancelled). Secondly, if you do live a long distance from your stations, the limiting factor is usually the noise figure of the front end of your receiver. The noise figure of the FM boosters is usually no better, if not worse than most receivers. Finally, the boosters also amplify all the strong stuff and usually cause overload problems (and make the multipath worse).
john@newave.UUCP (John A. Weeks III) (05/04/91)
In article <1991May2.113020.17346@nntp-server.caltech.edu> nyet@nntp-server.caltech.edu (n liu) writes: > I was paging though Crutchfield the other day when i came > upon a fm signal booster for ~30 bucks. Now, i thought to > myself, I wouldn't mind trying one of those out, since > my rather cheezy tuner don't lock into the stereo carrier > too good. But I wasn't about to buy it, for several reasons.. An amplifier cannot make a signal where no signal exists. If you have a fairly solid signal, but just a bit noisy, a booster might clear things up. If you have any mulit-path interference (the radio equivalent of ghosts), the amplifier will just make things worse. An FM booster also tends to reduce the selectivity of the tuner, so you might also have new problems with close stations bluring togather. The best thing you can do for your FM is check out your current antenna. Those rubber duck things just do not have the reception power of a 3 or 4 foot steel whip antenna. If you do want to try an amp, go to one of those places that have a 30 day return policy. Best Buy does, and I'm sure that you have something similar on the left coast. > So, hell, how hard could it be to just build one of these > suckers? So what kind of components/gain/etc. should i be > looking for? I've built minor audio amps, etc. but i'm not > to familiar with the MHz range... Any recommendations? Lots hard. An RF circuit is just as much mechanical as it is electrical. Murphy dictates that you should try building an RF oscillator, because most RF amps will oscillate.... -john- -- ============================================================================= John A. Weeks III (612) 942-6969 john@newave.mn.org NeWave Communications ...uunet!tcnet!wd0gol!newave!john