GRE 3001 Pre-Amp Experience Anyone?
 

I use a BC-780XLT and an Icom R-7000 coupled together with a
Stridesberg two port passive multicoupler.

This setup works well except the coupler sucks about 4 dB out of the
signal.

Since many of my targets are already weak, I'm looking to replace the
4 dB.

Wonder if anyone has experience using the GRE 3001 preamp at LOW GAIN
settings

I've seen all sorts of horror stories about pre-amps, and no one
comments on the gain setting they used. I suspect many ran the things
on the max 20dB setting.

All I want to do is overcome the losses in the coupler (without having
to buy the 4 port active coupler as these things are pricey).

Comments anyone?

73 Tom

Tom M wrote:
I use a BC-780XLT and an Icom R-7000 coupled together with a
Stridesberg two port passive multicoupler.

This setup works well except the coupler sucks about 4 dB out of the
signal.

Since many of my targets are already weak, I'm looking to replace the
4 dB.

Wonder if anyone has experience using the GRE 3001 preamp at LOW GAIN
settings

I've seen all sorts of horror stories about pre-amps, and no one
comments on the gain setting they used. I suspect many ran the things
on the max 20dB setting.

All I want to do is overcome the losses in the coupler (without having
to buy the 4 port active coupler as these things are pricey).

Comments anyone?

73 Tom

I use a GRE Preamp but only for a specialzed use, to receive MilSats
using a Yagi cut just for that band. For this purpose it works great,
even at 20 dB gain. However the same GRE Pre amp on a wide band ant
(even with gain set to minimum) has caused me both FM overload and
increased interference problems (and I'm not real near an transmitters).

So I do like the GRE Preamp but only when on an antenna which will only
receive the band you're interested in.

I've been using Stridsburg multicouples for some time, however I only
use the amplified modeles. They simply are GREAT! I have 2 of the 4
port versions and an 8 port version for VHF/UHF. Soon I'll be buying
another VHF/UHF 8 port model as well as a 4 port HF model. But I always
suggest spending the extra $$ and get the active version, you'll be
happier in the long run.

As a side note, if you need to you can cascade two multicouplers
together with no adverse effects. I do this often. Stridesburg has
suggested not to cascade more than two units, I've only ever done two
units and it works great, most of what I monitor are MilAir signals most
of which are well over 100 - 200 miles away on UHF.

George
http://www.MilAirComms.com
http://www.MilAirComms.com - Shack Pics including Multicouplers.

George,

I'm not sure I see any difference between using the GRE for low gain,
or the Stridesberg active coupler for low gain.

Why would one cause problems and the other not (or is this not the
message you're trying to send).

Thanks for the notes on your gadgets. Sounds like a nice setup.

Tom



(Tom M) wrote in message . com...
I use a BC-780XLT and an Icom R-7000 coupled together with a
Stridesberg two port passive multicoupler.

This setup works well except the coupler sucks about 4 dB out of the
signal.

Since many of my targets are already weak, I'm looking to replace the
4 dB.

Wonder if anyone has experience using the GRE 3001 preamp at LOW GAIN
settings

I've seen all sorts of horror stories about pre-amps, and no one
comments on the gain setting they used. I suspect many ran the things
on the max 20dB setting.

All I want to do is overcome the losses in the coupler (without having
to buy the 4 port active coupler as these things are pricey).

Comments anyone?

73 Tom

Tom M wrote:
George,

I'm not sure I see any difference between using the GRE for low gain,
or the Stridesberg active coupler for low gain.

Why would one cause problems and the other not (or is this not the
message you're trying to send).

Thanks for the notes on your gadgets. Sounds like a nice setup.

Tom


Good question which I'm not sure I know the answer to. However one
thing I do know is that on the GRE the lowest possible gain is 10 dB
where as the Stridesburg is only 4 dB. So there's a 6 dB difference.

Now I'll take a guess at another idea...I would say the Stridesburg is
better built and better shielding. It has a heavy cast aluminum case
were as the GRE has a much thinner case. Also the Stridesburg might
have a lower noise figure.

George
http://www.MilAirComms.com

George,

Thanks for the additional comments. I was hoping the GRE could be
turned down lower than 10dB. I think the R-7000 can take a bit of
gain as it is pretty intermod resistant, but I have no such hopes for
the BC-780XLT.

Perhaps surgery on the amp is on order, or a lower supply voltage to
limit its output?.

No question, the Stridesberg construction is tight.

73 Tom


GeorgeF wrote in message news:3F8AA5A1.20505@licensed4funREMOVEBEFOREFLIGH T.com...
Tom M wrote:
George,

I'm not sure I see any difference between using the GRE for low gain,
or the Stridesberg active coupler for low gain.

Why would one cause problems and the other not (or is this not the
message you're trying to send).

Thanks for the notes on your gadgets. Sounds like a nice setup.

Tom


Good question which I'm not sure I know the answer to. However one
thing I do know is that on the GRE the lowest possible gain is 10 dB
where as the Stridesburg is only 4 dB. So there's a 6 dB difference.

Now I'll take a guess at another idea...I would say the Stridesburg is
better built and better shielding. It has a heavy cast aluminum case
were as the GRE has a much thinner case. Also the Stridesburg might
have a lower noise figure.

George
http://www.MilAirComms.com

JUST ADD A VARIABLE ATTENUATOR ON THE OUTPUT OF THE AMP

JER1538A wrote:
JUST ADD A VARIABLE ATTENUATOR ON THE OUTPUT OF THE AMP

That's a possiblity. However now I would start thinking of cost. When
you add an attenuator, GRE pre-amp, and non amplified Stridberg you
might be just as costly as buying the amplified version and not have the
extra hassles....

Also remember the GRE preamp probably has a higher noise figure than the
amplified version of the Stridsberg.

George
http://www.MilAirComms.com

Since I already have the passive Stridesberg, and the GRE is only $40,
I'll go for the GRE and add a tee network pad to tame it to the min
gain I want, e.g. if the GRE min gain is 10 db as stated herein and I
need 4db to make up for the coupler losses, then I'll add a 6-7 db pad
to the output of the GRE to do the job.

I suspect the BC-780xlt may howl on certain freqs but the R-7000 will
be OK. That thing is bullet proof.

73 Tom





GeorgeF wrote in message news:3F8B5B34.9030700@licensed4funREMOVEBEFOREFLI GHT.com...
JER1538A wrote:
JUST ADD A VARIABLE ATTENUATOR ON THE OUTPUT OF THE AMP

That's a possiblity. However now I would start thinking of cost. When
you add an attenuator, GRE pre-amp, and non amplified Stridberg you
might be just as costly as buying the amplified version and not have the
extra hassles....

Also remember the GRE preamp probably has a higher noise figure than the
amplified version of the Stridsberg.

George
http://www.MilAirComms.com

I reviewed a GRE Super Amplifier in
April 2003 Monitoring Times. It is the smaller model,
designed for use with portable scanners.

The GRE Super Amplifier I tested (s/n 93156349) is
best suited for improving the performance of insensitive
scanners and test equipment when used with an inefficient antenna.
You may experience intermod if there are strong signals in your area.

--
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Bob Parnass, AJ9S GNU/Linux User http://parnass.com