Jim M75 Pre-Amplifier
- Thread starter Attackron
- Start date
- Status
hoser147
Member
Many times they overload the front end and end up doing just the opposite of what you want...........Hoser
Turbo68
Member
I agree with hoser about the preamps and sometimes you end hearing more hiss than audio.
Regards Lino.
Regards Lino.
dodgelover93
Member
pre amp
with the Jim M75 Pre-Amplifier on my bct15x uniden scanner how much improvement will I receive on the 400 mhz bands ? I live in windsor ontario and I'm looking to pick up more stuff in Michigan ..how many extra miles does the pre amp make your scanner receive ? I'm using the back of set stock antenna..
Also does anyone know the frequencies for Tim Hortons Essex Ontario Canada ?
with the Jim M75 Pre-Amplifier on my bct15x uniden scanner how much improvement will I receive on the 400 mhz bands ? I live in windsor ontario and I'm looking to pick up more stuff in Michigan ..how many extra miles does the pre amp make your scanner receive ? I'm using the back of set stock antenna..
Also does anyone know the frequencies for Tim Hortons Essex Ontario Canada ?
KC4RAF
Member
Can't answer your last question, but;
as others have posted in this very aged thread, you're more than likely going to raise the noise floor than to help you hear far off stations/signals. Been there, done that; and I don't use a pre-amp. Your best bet is to invest in a GOOD antenna; maybe even a yagi.
as others have posted in this very aged thread, you're more than likely going to raise the noise floor than to help you hear far off stations/signals. Been there, done that; and I don't use a pre-amp. Your best bet is to invest in a GOOD antenna; maybe even a yagi.
dodgelover93
Member
is the D130NJ Diamond Super Discone Antenna a good antenna ? how much will the D130NJ Diamond Super Discone Antenna improve my reception on the 400 mhz band and on air traffic bands? . what will be the range i will be expecting with this nice antenna?
i had hand held scanners before but this will be my first base set up with thew diamond antenna .. im using the uniden bct15x thanks.. I also live in windsor ontario...I'll scrap the pre amp idea and go with the antenna .. is that good?
i had hand held scanners before but this will be my first base set up with thew diamond antenna .. im using the uniden bct15x thanks.. I also live in windsor ontario...I'll scrap the pre amp idea and go with the antenna .. is that good?
dodgelover93
Member
D130NJ Diamond Super Discone Antenna what mounting gear to I get for antenna im shopping at scannermaster.com.. or does it come with mounting gear ? im new to base antennas thanks..
VancouverScan
Member
They can work well but you will need to learn when to turn it up and when not to. The Jim models and the AOR Pre-Amp work quite well for the right signals.
You can get a better signal, when you acquire your outside antenna, if you stay away from RG-58 coax and try to limit your coax length to less than 100'. If you are going to invest in a great antenna, do the same with the coax required to connect to your scanner.
The old saying: put most of your money into the antenna and coax, whatever you have left over, buy your radios.
I have had that exact preamp for many, many years and it performs very well. As other have said, you need to know when to amplify, when to leave the signal alone, and when to attenuate. That's exactly the reason I bought that particular preamp years ago - it can attenuate as well as amplify, and because of the different range settings. In general, a better antenna is a better investment than an amp. However, a better antennas AND an amp can be a great combination, just as long as you don't amplify when it's not needed. Knowing when to amplify is, like everything else in radio, trial and error.
I'm not sorry I bought mine and I do use it frequently.
Best regards - David
I'm not sorry I bought mine and I do use it frequently.
Best regards - David
One more not about that preamp - the different ranges are different bandpass filters. Since the RSP has no built in bandpass filters (other than the tracking filter in the tuner chip itself), the addition of bandpass filters can help a great deal with minimizing strong signals in bands you don't want to hear, especially AM and/or FM broadcast bands.
This thing is giving you 3 products in one box - bandpass filters, attenuator and preamp.
This thing is giving you 3 products in one box - bandpass filters, attenuator and preamp.
rbm
Member
I have six Jim M-75's.
I paid full price for the first one a long time ago. (Far too much money!)
Then I bought the other five on ebay over the years. Most of them from the UK.
They work great if used 'sparingly'.
One nice thing about them is you can adjust the gain to fit your needs.
I use four of them in the feed lines to different areas of the house and adjust each for peak performance with no intermod.
Edit:
On those I have in everyday use, I built a three terminal regulator into each and use a wall wart to power them.
Rich
Here is a photo of about one third of my spare preamps.
.
I paid full price for the first one a long time ago. (Far too much money!)
Then I bought the other five on ebay over the years. Most of them from the UK.
They work great if used 'sparingly'.
One nice thing about them is you can adjust the gain to fit your needs.
I use four of them in the feed lines to different areas of the house and adjust each for peak performance with no intermod.
Edit:
On those I have in everyday use, I built a three terminal regulator into each and use a wall wart to power them.
Rich
Here is a photo of about one third of my spare preamps.
.
Last edited:
- Status
Similar threads
