GRE super amplifier

[jrff1752]

Hello, I recently purchase a GRE super amplifier off eBay. I made sure there was a brand new battery installed and attached it to my Pro 106 scanner. I was hearing transmissions fine and then when I flipped the power switch on, the transmissions immediately stopped. I'm listening to a P25 system. Are there settings on my scanner I need to use for this Amp to work or is it just broken? Any help would be appreciated.

Thank you

 

[jrff1752]

Also, just out of curiosity, we have a 180' tower with all kind of signals and a very powerful radio station 1000' straight west of our house. How much could that be affecting my scanner signals. Like I said, I'm listening to a p25 system. The repeater is actually north of my house about 4 miles.

 

[vagrant]

1. Do not turn that amplifier dial past the halfway point. It is simply too much gain.
2. Use a filter inline on your coax before the amplifier. Antenna - Filter - Amp - Scanner

Use the URL in my signature to find out about FM filters. Additionally, you may need other filters as well.

 

[tvengr]

Which P25 system are you trying to monitor and what is your city or town, county, and state? The GRE scanners are easily overloaded. That is most likely the case with the additional amplification. The preamp itself may be overloaded. Try turning on the attenuator to see if that helps. Is it an AM or FM radio station?

 

[DeeEx]

1. Do not turn that amplifier dial past the halfway point. It is simply too much gain.
2. Use a filter inline on your coax before the amplifier. Antenna - Filter - Amp - Scanner

Use the URL in my signature to find out about FM filters. Additionally, you may need other filters as well.

I was going to say filtering number one, and second of all...you’re better off spending money getting a better antenna and/or getting your antenna higher in the air, rather than buying a preamp.

Pretty soon you’ll learn that preamps amplify everything and you’ll either want to use it on only a few frequencies, or sell it on eBay. It will annoy you to no end if you leave it on all the time with the gain turned up.

 

[Ubbe]

Are there settings on my scanner I need to use for this Amp to work or is it just broken? Any help would be appreciated.

The proper way to set the gain, or the attenuation of a variable attenuator, are to listen in analog mode to a weak signal with a lot of noise in the same frequency band and adjust from a low gain setting and slowly increase gain until it can't be improved anymore. Go back and forth in gain to find the middle of the two settings where the noise increase due to a too low gain and too much gain.

/Ubbe

 

[iMONITOR]

Hello, I recently purchase a GRE super amplifier off eBay. I made sure there was a brand new battery installed and attached it to my Pro 106 scanner. I was hearing transmissions fine and then when I flipped the power switch on, the transmissions immediately stopped. I'm listening to a P25 system. Are there settings on my scanner I need to use for this Amp to work or is it just broken? Any help would be appreciated.

Thank you

Based on that wouldn't you solve the problem simply by not using the preamp?

 

[K7ULS]

Does the red light on the front come on when you slide switch to on? I've been using one for 30 years with external wall adapter and the only problem is the on/off pass switch needs to be moved a bit back and forth due to it's age so try it on a WX frequency with gain control all the way to max to see if you get something if not it's prob fubar.

 

[gmclam]

Hello, I recently purchase a GRE super amplifier off eBay. I made sure there was a brand new battery installed and attached it to my Pro 106 scanner. I was hearing transmissions fine and then when I flipped the power switch on, the transmissions immediately stopped. I'm listening to a P25 system. Are there settings on my scanner I need to use for this Amp to work or is it just broken? Any help would be appreciated.

Also, just out of curiosity, we have a 180' tower with all kind of signals and a very powerful radio station 1000' straight west of our house. How much could that be affecting my scanner signals. Like I said, I'm listening to a p25 system. The repeater is actually north of my house about 4 miles.

Thank you

This makes me wonder why you feel you need an amplifier. If it's working, why break it?
YES that broadcast station is part of the equation. AM/FM/TV broadcast, pager transmitters and cell towers are notorious for "interfering" with scanner reception. I put that in quotes because it's typically not their fault. Because all the signals will go through the amp, dictated by the strongest, you'll need to filter out what you don't want before amplification. Hopefully the undesired signals are not too close in frequency to the desired signals.

 

[K7ULS]

Receive Filters

 

[Ensnared]

I once asked a GRE representative about the amplifier they sold. He told me that it would also amplify any noise encountered. Hence, I never bought one. I relied on antennas to increase reception on the PSR 500 I owned.

 

[dlwtrunked]

Yes, an amplier will also amplify noise but that does not mean it will not help reception. The eason to add an amplifier to any decent scanner is to improve the signal-to-noise ratio. That requires the amplifier to have a lower noise figure than the scanner front in and enough gain to make that matter (Frey's ). I am not sure a GRE pre-amplier will satisfy that. Next, one has to look out for receiver overload from stations not even on the frequency that you are listening to de-sensing the scanner or causing intermod. Expermentation and money (filters) are often necessary in many environments--simplify thinking a prepamp without doins such is asking for disappointment. (Many decades of experience with everything from a Bearcat 210 to an ICOM R9500 and and ICOM R8600 to many different SDR receivers.)