Scanner "Pre-Amplifier" system

ffemtrfc1 · #1 (**permalink**) 10-08-2009, 11:25 AM

Anyone use or have any luck on a digital P25 800mhz Motorola type II system with a scanner amplifier such as this one :

WRP-1300 Pre-Amplifier for Wideband Scanners

I was looking at getting one, but wasn't sure if this would pull in better 800mhz p25 signals or not...someone out there that uses this for that please advise the quality or if its worth getting.

Thanks

ka3jjz · #2 (**permalink**) 10-08-2009, 11:37 AM

Short and sweet - improve your antenna/coax situation before considering any amplification. Get the antenna outside, higher, better coax first....73 Mike

ffemtrfc1 · #3 (**permalink**) 10-08-2009, 12:10 PM

Thank you ka3jjz for the response,

I will look into that. Thanks!

wvscanner · #4 (**permalink**) 10-08-2009, 03:01 PM

I use one from GRE at least it has a male connector on one end runs from battery or ac and adjustable gain. I haven't got to try a 800mhz digital system but I found that on my 800mhz edac system it really depends on which scanner I have it one if it helps any or not. For my 400mhz digital it is a life saver. They have been posting in the past about how well they work. I think in short it will depend who made your scanner, and if you live in RF active area.

Also GRE is cheaper.

gmclam · #5 (**permalink**) 10-08-2009, 07:06 PM

Quote:

Originally Posted by wvscanner

... but I found that on my 800mhz edac system it really depends on which scanner I have it one if it helps any or not. For my 400mhz digital it is a life saver. They have been posting in the past about how well they work. I think in short it will depend who made your scanner, and if you live in RF active area...

Amen to that. It is ironic how many people think they need an amplifier when they actually would be better off installing filters. you need to start with a good antenna. If the antenna can't pick up the signal, all an amplifier will do is amplify noise.

I did a sweep on the RF from my discone and found that the broadcast FM signals (88-108 MHz) were much stronger than any signal I wanted to hear with a scanner. After installing an FM band stop filter, I found a paging signal that was still 10dB hotter than any "scanner" signal. Adding an amplifier will amplify that signal as well as what I want, and that will just make the AGC in the scanner drop everything back down.

One place where an amplifier might be effective is when it is used near the antenna to compensate for line loss, especially at the higher frequencies. But again if you are near a strong RF source, that needs to be filtered before the amplifier. Plus you are better off using the best low loss coax you can find.