SDS100/SDS200: Preamp worth it?

[TxScanner]

I just saw Scannermaster had a Jim MD75 preamp for scanners on sale, at 149, would it be worth it on sds100?


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[SCPD]

Take a look at the Moonraker M-100 or MRP-2000 and read this link about pre-amplifiers
https://forums.radioreference.com/splitters-filters-multicouplers/264851-pre-amp-question.html
https://www.youtube.com/watch?v=FvxLNP2bspk
https://www.ebay.com/itm/Wideband-L...plifier-HF-VHF-UHF-Receiver-HAM-/183347237959

 

[TailGator911]

I have invested in scanner preamps before with little success. You will always boost noise right along with your signal so that system 50 miles away that is barely receivable with all the static comes in louder with all of the static and noise right along with it. Attenuating it usually did not help me, only amplified what I already could not decipher. I always had better luck experimenting with antennas and placement. Just my 2-cents...

JD
kf4anc

 

[dlwtrunked]

I have invested in scanner preamps before with little success. You will always boost noise right along with your signal so that system 50 miles away that is barely receivable with all the static comes in louder with all of the static and noise right along with it. Attenuating it usually did not help me, only amplified what I already could not decipher. I always had better luck experimenting with antennas and placement. Just my 2-cents...

JD
kf4anc

My experience with good (expensive pre-amps with a low noise figure) pre-amps and notch filters for strong nearby signals on my end has been different.. The main spec to look at for a pre-amp is to get one with a low noise figure and enough gain to make use of that. Most noise at VHF/UHF is usually receiver noise and the pre-amp must do better than to counter that (Freii's formula https://en.wikipedia.org/wiki/Noise_figure). And then a good 3rd intercept point If it costs less than $100, it is generally not going to be good enough; it took me a long time to discover that. And if too close to high powered transmitters, there are going to be problems unless you invest in not filters. One should always notch the FM broadcast band (where cheaper filters do work. It is amazing how often that (de-sense of the receiver by the strong FM station on another frequency affecting the receiver AGC) is the problem although the listener does not know it as he/she does not hear the FM station. That is my experience of over 40 years using everything from a old Bearcat BC-120 to an ICOM R-9500. Summary: Adding a pre-amp requires a pre-amp with low noise filter and will very likely require notch filters that may be unique to the location; always use an FM broadcast band notch filter (even if you do not think that is a problem. Expect to often pay in the multiple $$$ range for the right hardware to do this; and experimentation with notch filters is often going to be required.

But I do strongly agree that antennas and placement should be a first consideration.

 

[hardsuit]

No, the JIM preamp is not worth it if you have a Uniden or Whistler, they are not sensitive receivers like the ICOM and AOR communication receivers. you will amplify the noise as well as the transmission in a Uniden or Whistler. instead try using a High Gain antenna like a RS telescoping HAM antenna, its 6" - 26" and is center loaded so no ground plane is needed, you can tune the antenna. or an External antenna always improve reception.

 

[TxScanner]

Thanks all for the info


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[SCPD]

Saw one on Ebay Jim M-75 Low Noise Pre-Amplifier for $115
https://www.ebay.com/itm/Jim-M-75-L...re-amplifier&_from=R40&rt=nc&LH_TitleDesc=0|0

 

[wtp]

years ago

when i started to listen to scanners and i thought about trying to hear the cars that were 12 miles away.
i thought about getting an amplifier.
and then i realized, i could hear the base i don't think i need to hear the car.
too much money and work for very little gain.
and now the county i am in a can hear a car 30 miles away on the trunking system.
so, i still don't need one.

 

[T-Santon]

I've had great success recently with just a cheap 24 dollar RCA TVPRAMP1E and a very cheap MCM FM trap filter (between antenna and preamp)... But I also live in the sticks, so a few nearby FM stations are the only thing I have to worry about.

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[iMONITOR]

J.I.M. M75 low noise wideband pre-amp 24-2140MHz
Model: 400986451321

$89.95
$43.99 Save: 51% off
https://www.generalspot.top/jim-m75-low-noise-wideband-preamp-242140mhz-p-9156.html

 

[blackbelter]

I have had that over priced M75 before and sold it as it pulled more noise than audio.
Invest in a better antenna.

 

[ka3jjz]

And don't forget the coax while you're at it - otherwise it's akin to putting too much pressure in a leaky water hose. You're not going to get much of a bang for your buck without it, because the wrong coax is going to cost you in signal strength

Mike

 

[sibbley]

A few months ago I had the opportunity to purchase 2 new in box GRE Super Amps. I couldn't believe I found them, but there they were on Ebay. Anyway, I've been using 1 daily to boost signal for my antenna setup at work and it's working very well.

My setup is this: a SpectrumForce 800MHz (which works quite well across all bands) mag mount antenna, mounted on the single story building I work in (about 12' high). The antenna is run to a Stridesburg passive 4 port multicoupler which feeds 4 scanners.

 

[sibbley]

I've had great success recently with just a cheap 24 dollar RCA TVPRAMP1E and a very cheap MCM FM trap filter (between antenna and preamp)... But I also live in the sticks, so a few nearby FM stations are the only thing I have to worry about.

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I also use a 4 port TV preamp at my ST-2 to boost the signal sent to my 8 port active multicoupler. It make a huge difference.