Anyone using an AM/FM signal booster?

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radio10-8

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I have a Radio Shack 12db AM/FM powered signal booster. I was going to install it in my truck because I do travel in outlying areas and this could be good to keep my listening to my station without alot of static. Before I did install it I thought I would ask here first.
Also if I modified the antenna cable with a BNC I could attach this to a scanner. Has anyone already tried this and what results did you have. Thanks..
 

zz0468

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A scanner in a car really doesn't need any type of "booster", especially something designed for broadcast use from Radio Shack. You're very likely to find it makes things worse, at least in some parts of town. If you drive out of the coverage area of a system you like to listen to on scanner, just say goodbye until you drive home. You'll live, and the radio will be happier around town.
 

key2_altfire

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If that AM/FM booster is for broadcast band, your scanner will probably be out of its frequency range for most of your scanning. This will probably attenuate the RF rather than boost!
 

radio10-8

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Maybe I misinformed or misdirected my question

This signal booster does NOT broadcast anything. It is only to boost the reception signal of the AM/FM bands. If yo live in a rural area the booster will boost the signal of the AM/FM radio signals. It has no transmitting capabilities. Thats why I was asking what could this do to a mobile scanner if changed to a BNC connector? My scanners do have AM/FM reception.
 

Tishers

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radio10-8 said:
This signal booster does NOT broadcast anything. It is only to boost the reception signal of the AM/FM bands. If yo live in a rural area the booster will boost the signal of the AM/FM radio signals. It has no transmitting capabilities. Thats why I was asking what could this do to a mobile scanner if changed to a BNC connector? My scanners do have AM/FM reception.
I think the previous poster meant "broadcast band" and not per sec broadcast as in transmitting. The broadcast bands are 540 Khz to 1.8 mHz (AM radio) and 88.0 mHz to 108 mHz (commercial FM radio).

Most every pre-amplifier out there also amplifies the ambient noise and also generates it's own noise (every semiconductor device in the world does this) that add to the overall noise figure of the system. Also, few amplifiers are truely broadband and can handle from 500 KHz (lower end AM band) to and through 108 MHz (upper FM).

Most scanner users are listening to 30-50 MHz, 108 to 174 MHz (aviation and VHF), 420-512 MHz (UHF) and the 800 to 960 MHz bands. The Radio Shack pre-amp may give you some gain in the VHF band but it may have a negative gain (loss) in the UHF and 800-960 MHz bands.

I have used pre-amps before with good results but usually as a last result. Working on antennas, height, feedline and good installation practices (not side mounting an omni too near the tower, weatherproofing connections, etc...) give much better improvements to listening.
 

kb2vxa

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Radio, had you taken the time to read the posts about "booster amps" you would have had your question answered many times over. The one you're looking at is the bottom of the barrel, the worst of the worse of those "DC to light" amplifiers. In the presence of even moderately strong signals anywhere from kilohertz to nearly a gigahertz it'll cause overload interference and out in the middle of nowhere it will amplify the slightest electrical noise.

I tried one once and it destroyed my AM/FM reception, finding no area where it was of any use I removed it and reception returned to normal. I hate to think what it would do to a sensitive scanner front end if it made such pig poop out of the radio in the dash.
 

key2_altfire

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Tishers said:
Most every pre-amplifier out there also amplifies the ambient noise and also generates it's own noise
Tishers, good points all around... I think "its own noise" in terms of intermodulation distortion could quite possibly be the worst thing an AM/FM booster has going for it.
 

radio10-8

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Thanks to all!

Yes, Warren I did not read previous posts on this subject. I rarely do search the forums. I have taken your advice and I am NOT installing this thing anywhere..
 

N9JIG

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Radio10-8; You might be better off with a TV style amplifier if you really need a signal boost. The TV bands are similar enough in frequency to the various scanner bands that a wide band pre-amp like a TV amp will usually work as well with a scanner.

That said, scanners today rarely need external amps, even in rural areas. As others have said, an amp also makes noise stronger. I use a Wingard TV amp at home on an Icom R8500 and it works great, but only because the R8500 has a very good front end. Less expensive scanners, including GRE, Uniden and Radio Shack, will usually suffer from front end overload or other interference problems with an amp.

You might actually find better results going the other way around, using attenuators.

Good Luck!
 

radio10-8

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Thanks Rich,

My scanners are working fine without an amp. I found this thing in a box of my old wires and junk and I said to myself I need to play with this. It does work nicely on teh am/fm radio I tested it on. But I will leave it alone for the scanners.
 
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