Radio Shack Amplifier 100-1000 MHz Cat. No. 20-0041

[JASII]

I ran across something recently at my house that is marked:

Radio Shack
AMPLIFIER
100-1000 MHz

on one side. On the other side it is marked:

Radio Shack
CAT. NO. 20-0041
AMPLIFIER

It has male BNC connector on one end and a female BNC connector on the other end. I opened it and it looks like it can use a 9 volt battery for power.

Can anybody here tell me anything more about this?

It looks quite similar to the GRE Super Amplifier on Universal Radios legacy webpage.

GRE Super Amplifier Preamp

 

[kc2asb]

I have no experience with the amplifier you have, but have seen the GRE model. GRE made a lot of electronics gear for Radio Shack over the years, including scanners, shortwave radios, etc. A very good chance that the GRE Super Amplifier is the same as the Radio Shack model you have in hand. I believe it was primarily made for use with handheld scanners.

 

[dave3825]

If it takes a 9 volt it’s more than likely similar to the GRE. Have any pics?

 

[trentbob]

I ran across something recently at my house that is marked:

Radio Shack
AMPLIFIER
100-1000 MHz

on one side. On the other side it is marked:

Radio Shack
CAT. NO. 20-0041
AMPLIFIER

It has male BNC connector on one end and a female BNC connector on the other end. I opened it and it looks like it can use a 9 volt battery for power.

Can anybody here tell me anything more about this?

It looks quite similar to the GRE Super Amplifier on Universal Radios legacy webpage.

GRE Super Amplifier Preamp

I don't recognize this as a Radio Shack product, amazing.

I've always kept my GRE super amplifier and portable super amplifier in superb condition, in my drawer, right at my fingertips, new condition.

I would think the amplifier you show is very similar, I agree.

With the amplifier, remember that you are amplifying the noise also but, back in the day I found that when trunked 800 MHz SmartZone analog first came out the GRE amplifiers actually did increase the quality of the transmission. Those units did very well on UHF, not so much VHF but they were tunable with the dial. Although Uniden did make some Radio Shack radios, GRE was the main supply of pro-xxxx radios.. the best being the 2004-5-6.

The oldest GRE Radio Shack item I have and can remember buying is a slide rule dial Pro 1 desktop receiver.. very thick metal chassis, bright dial. That was made by GRE Japan for Radio Shack in the late sixties.

 

[trentbob]

Just to clarify with the GRE super amplifiers, there were two.. you had a base model with a 9-volt power supply that that would go in between your feed and antenna intake, then they had a portable super amplifier that used a 9-volt battery or a power source and that went in between the radio and the BNC connector on the rubber duck.

 

[JASII]

 

[trentbob]

View attachment 181810View attachment 181812

That is a clone of the GRE super amplifier for Portables, I have never seen a Radio Shack version like this, very cool. That little dial on the back made all the difference.

 

[kc2asb]

The oldest GRE Radio Shack item I have and can remember buying is a slide rule dial Pro 1 desktop receiver.. very thick metal chassis, bright dial. That was made by GRE Japan for Radio Shack in the late sixties.

Was the Pro-1 a single band receiver? Some years back when I was still collecting radios, I picked up a Pro-2 (VHF-hi VHF-lo) and a Pro-3 (VHF-hi,lo and UHF). Both of mine are dated coded 1970, older than me LOL. As you said, very solidly built. The two I have performed better than I expected. I was monitoring the NYPD on the Pro-3 maybe 2-3 years ago. IIRC, the Pro-2 had a switch to toggle between AM or FM modulation, which I found strange since it does not cover the aircraft band.

(Apologies to the OP for going off topic)

 

[kc2asb]

Thanks for posting the pic! Are you going to put it to use?

 

[JASII]

Thanks for posting the pic! Are you going to put it to use?

I am still trying to determine how want to power it. There are some 9 volt "battery eliminators" on Amazon that might work for this.

 

[trentbob]

I am still trying to determine how want to power it. There are some 9 volt "battery eliminators" on Amazon that might work for this.

Yes if you're going to use it permanently on a base unit, I would definitely get a wall wort. You do tend to leave them on, I always forgot to reach around and use the slide switch which bypasses the amplifier but does compromise reception a little bit. If you're not going to use it at all just remove it so it doesn't interfere with reception when it's shut off.

 

[prcguy]

If it runs off a 9v battery its probably made to use with a portable antenna. Plug in a good base antenna and be ready for lots of preamp overload.

 

[vagrant]

1. Pay attention to the voltage polarity for the external DC connection port.
2. 20 dB gain is ludicrous. Use that dial on the back set to half, or less.
3. Put any filters inline between the antenna and the amp.
4. Rechargeable 9v are probably your friend with this when portable.
5. Experiment with it turned off versus removing it entirely.

An SDR will show some numbers versus trying to discern differences using one’s ear.

 

[rgchristy]

This thread may help some:

GRE scanner preamp

so im looking into one of the older GREcom made preamps the ones that RS and then GRE sold (see pic) how do they work? and what power supply cord do i need to get all i know is it runs on 9 volt bat but i have no AMP's info for it all is says is 9VDC for ext plug

forums.radioreference.com

 

[kc2asb]

I am still trying to determine how want to power it. There are some 9 volt "battery eliminators" on Amazon that might work for this.

If you haven't done so already, why not buy a 9V battery and put the amp through a trial run? Find out if it works for your application before spending for a battery eliminator. Just a thought.