moonraker m100 or j.i.m. m 75 ?

[rob12770]

hi, so i had a moonraker m100 pre amp about a year ago, and was pretty impressed with it, it pulled in the weaker signals ok,
but now i am looking at the j.i.m. m75 pre amp, its £30 more , (£90) .. is it worth paying the extra, ? both go up to 20 db gain apparently, actually the m100 is meant to be 22db , but im thinking the j.i.m. is better made and a bit tighter ?
cheers rob.

[Andy]

I've had a Jim pre-amp since 1988 and it's been excellent. Variable gain, switchable filters. Mine is the M-100 (I think the numbers have changed over the years) and seems identical to the M75 as advertised now.

Edit: Hmmm - looking at the ads for both, I reckon they contain the same guts.

[moj]

i,ve also got the m-75 aswell and to be honest its been amazing at pulling in the signals and i don,t get any interference that a lot of other ppl sometime claim that they get when using one.

if your looking for a good preamp then thats what id go for m8

[rob12770]

i was gonna get the 75 but i got an m100 off ebay for £35 ..good enough

[troffasky]

It depends how sensitive your receiver is, or how susceptible it is to intermod and overloading. Use a preamp without filtering with the wrong receiver [eg Funcube Dongle] and every preamp will appear to be rubbish.

I suppose it's also possible to design a preamp that spews out rubbish on it's own, regardless of the receiver.

[rob12770]

yeah, for some reason, this one is pulling in a lot of buzzing with the signal if i have it on 24-2300mhz switch

maybey soneting to do with the scanner as said on above post.

[OnTheSide]

I've got a tapped 3500 which has a 5 bar signal strength indicator and a discone. DSD will decode anything as long as it registers at least a single bar on the indicator.

With some distant weak signals that can be heard but don't register on the signal strength indicator DSD struggles a bit and you hear broken sentences.

Will this help for that? Has anyone tried a pre amp with DMR? There's no hiss to amplify but will it boost the signal.

[radiosification]

I've got a tapped 3500 which has a 5 bar signal strength indicator and a discone. DSD will decode anything as long as it registers at least a single bar on the indicator.

With some distant weak signals that can be heard but don't register on the signal strength indicator DSD struggles a bit and you hear broken sentences.

Will this help for that? Has anyone tried a pre amp with DMR? There's no hiss to amplify but will it boost the signal.

I have never used a pre amp on a scanner but (theoretically) mostly they are not useful unless you have a long, lossy cable and are willing to connect the pre amp right by your antenna with very little cable in between.

For example my home's TV antenna has a pre amp because we wanted multiple TVs to be able to use freeview. The pre amp is right up on the roof next to the antenna to boost the signal before there are any losses in the cable. It needed the pre amp in this case because after splitting the signal, the strength may have been too weak