Moonraker M-100 Professional Scanner Pre Amplifier

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digitalanalog

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Has anyone used this amp?


Professional pre amplifier
24-2300MHz
Gain -10 to 22+ dB

High quality pre-amp with variable gain control and band pass filters to minimise interference.
Can be powered by its internal battery (1 x PP3 9v type) or from 12v dc psu (not supplied).
Perfect for any scanner or receiver

Key Features/Specifications:

  • Type: Wideband professional GaAs FET scanner receiver
  • Freqency: 24-2300MHz
  • Band A: 225-1500MHz
  • Band B: 108-185MHz
  • Band C: 24-2300MHz
  • Gain: -10 TO +22dB
  • Impedance: 50 Ohms
  • Battery: PP3
  • Complete with BNC patch lead

moonrakeramp.JPG

 

morfis

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Similar have been around for years and branded by Scannermaster, Garex and no doubt others.
Never found any of them to be paticularly useful but they still seem to sell fairly well to airband listeners (who it seems will buy just about anything regardless of fitness for purpose or expense).
My own experience of Moonraker stuff (antennas, never things like this) is that it has been very poor quality
 

digitalanalog

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Similar have been around for years and branded by Scannermaster, Garex and no doubt others.
Never found any of them to be paticularly useful but they still seem to sell fairly well to airband listeners (who it seems will buy just about anything regardless of fitness for purpose or expense).
My own experience of Moonraker stuff (antennas, never things like this) is that it has been very poor quality

So you think airband listeners are idiots and you never used one of these amplifiers.
Thanks for that information but that's not what I asked.
 

N9JIG

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This looks like it came from the same factory as the JIM M-75 amp. Same 3-way range switch and level control. The JIM however had a male BNC on the output (bottom) side so a jumper is not needed for HT's etc.

If you are in a rural area with a low noise floor you might seem some benefit with a wide-range amp like this but in an area with higher levels of RF it may not help much and even make things worse due to overload. Remember that an amp like this also amplifies RF noise from computers, routers and other devices. You are just as likely to make things worse with a pre-amp as make it better. Also remember that higher S-Meter indications are not always indicative of better reception, voice quality is the better tell.

In a base installation better results may be had by placing the amp at the antenna rather than the radio when practical.

I actually have a couple of these here at the desert HQ. I also have a GRE Super-Amp.

I have had some positive results and some negative. I tried connecting to the ST-2 in the attic both at the radio and at the antenna. There was some better performance both ways but it did increase the noise floor and I had to use a higher squelch setting.

I did remove it from the attic as I did not want it to cook up there in the Arizona summer last year. Also I did not have an outlet close enough to not need an extension cord. I then tried it at the radio on my R8500 and it had pretty much the same result.

Where it seemed to work the best for me however (and weirdly) was connected before the multicoupler. It seemed to help my Mil-Air reception noticeably but significantly increased the birdie count. I had some weird interference in the VHF High-band I found was from my drink fridge that became apparent with the amp but was not strong enough without it. (Spent several hours tracking that down!)

If you buy one of these be advised that it is a 50-50 shot that it will make things worse instead of better.
 

Volfirefighter

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I have used this one on Ebay and I can attest that it does indeed improve reception of frequencies on the fringe. I use it with just a Remtronix 800 Mhz SMA antenna to pull in a P25 800 Mhz trunked system that I was getting -100 dBm and now get - 60 dBm. I also hooked it up to my analog scanner with my attic-mounted scantenna and saw improvements of 2 to 3 bars of signal on VHF and UHF frequencies so I plan to get a second one.

 

digitalanalog

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Messages
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This looks like it came from the same factory as the JIM M-75 amp. Same 3-way range switch and level control. The JIM however had a male BNC on the output (bottom) side so a jumper is not needed for HT's etc.

If you are in a rural area with a low noise floor you might seem some benefit with a wide-range amp like this but in an area with higher levels of RF it may not help much and even make things worse due to overload. Remember that an amp like this also amplifies RF noise from computers, routers and other devices. You are just as likely to make things worse with a pre-amp as make it better. Also remember that higher S-Meter indications are not always indicative of better reception, voice quality is the better tell.

In a base installation better results may be had by placing the amp at the antenna rather than the radio when practical.

I actually have a couple of these here at the desert HQ. I also have a GRE Super-Amp.

I have had some positive results and some negative. I tried connecting to the ST-2 in the attic both at the radio and at the antenna. There was some better performance both ways but it did increase the noise floor and I had to use a higher squelch setting.

I did remove it from the attic as I did not want it to cook up there in the Arizona summer last year. Also I did not have an outlet close enough to not need an extension cord. I then tried it at the radio on my R8500 and it had pretty much the same result.

Where it seemed to work the best for me however (and weirdly) was connected before the multicoupler. It seemed to help my Mil-Air reception noticeably but significantly increased the birdie count. I had some weird interference in the VHF High-band I found was from my drink fridge that became apparent with the amp but was not strong enough without it. (Spent several hours tracking that down!)

If you buy one of these be advised that it is a 50-50 shot that it will make things worse instead of better.

Thanks Rich.
good to know, I also have some of the GRE super amps, I live in a very rural area and I have no noise floor at all , and without an amp my scanners go pretty quite, so I have to have them. I was just looking to see what was out there, I had seen these before and on scanmaster but was never impressed with the price. I will more then likley go with a Minicircuits amp( I need to add 2-3 more to my setup), their prices are good and even better for used ones on eBay, but they don't have gain control on a lot of them, with my GRE amps, Most times I move the gain to about an 8 (with 10 being full on) and it works perfect, full on seems to over load the front end on my old analog scanners, but back it off a little and it's perfect. so with no noise floor the amps other then overloading the front end some times, are a must for me. Yeah I have to adjust the squelch but i never use the ATT button it just about kills the signal. So again Thanks for your input on this model(or the same JIM model).

amps.jpg
 

N9JIG

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I had a couple of the MiniCircuit amps back in the old house and left them in the attic when I moved, I wish I would have recovered them and brought them here. They were awesome and would have been a lot more effective here in the desert than they were in the burbs where I lived before.
 

prcguy

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I believe the Moonraker preamp would be an Intermod generator for many people. You can get an idea of a preamps signal handling capability (IP1 and IP3 ratings) by how much power it consumes. If it runs from a 9v battery that's not a good sign.

The only preamp I've found that will work in my area for not creating Intermod in a MiniCircuits ZHL-1010 with an IP1 or 1dB compression point of 26dBm and an IP3 of 46dBm. It runs off 12 volts and draws over a half amp and its only got 10dB gain. Something that runs from a 9v battery for more than an hour is probably going to be in the 1dB compression range of 0 to 10dBm at the most. That's probably why it has a gain control, so you can try and operate it in a range where it won't trash your reception too bad.
 

prcguy

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Your lucky, many of us have to use very high level amps that cost a little more than $7. Here are a couple of MiniCircuits ZHL-1010s and a 20dB gain version the ZHL-2010 I stocked up for future projects along with a really good MiniCircuits FM notch filter and HP limiter.


22.JPG

I use a regular $7 Satmaxium TV signal amp from eBay it works very well just saying
 

prcguy

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prcguy

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The 152 stuff is easy, I have a couple of old PAR 152MHz notch filters somewhere. They show up cheap on Ebay or you can probably still order a new one. Have not seen them offered for UHF but you can also find single cavity UHF notch filters on ebay. They are big but work great.

Now I just need to find one for 152.8000 and 462.8000 to kill some local paging at 250 watts 5 miles away that kills some of my 152.00 153.00 462.00 and 463.00
 

Ubbe

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The secret to using an amplifier sucessfully are to not have the scanner being feed with a too high signal level. It will first start to de-sense and if the signal are strong enough it will overload and go into intermodulation where you'll hear a lot of frequencies spread over the whole freqeuency band where they actually are not sent over the air, they are produced in the scanner.

Active multicouplers can be sensitive to overload, like Stridsberg, that doesn't like seeing stronger signals on it's input. Stridsberg even did a modification to one guys multicoupler to reduce the input signal as he had nearby transmit towers that ruined the reception in the multicoupler.

If an amplifier doesn't have a variable gain control, then you probably must use an external attenuator after the amplifier to reduce the signal to a safe level. A variable 0-20dB attenuater are perfect for this use.

An example of a good $30 low noise amplifier that can handle fairly large signal levels are this one: Ultra LNA 2GHz Gain>20dB PGA103 ESD Gain Stabilization USB cable PGA-103 NF .5dB | eBay

You have to add cables and connectors to suit your needs and add a $15 variable attenuator like this one, or use fixed attenuators if you know how much to attenuate: ATTENUATOR IEC or F type in line aerial signal reducer 3 6 9 12 15 20dB variable | eBay

A good FM trapfilter are always a good investment, something that doesn't attenuate the VHF airband if you are critical listener to that band.

/Ubbe
 
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