PMR 446 Mhz

[MajicM]

Hi, wondered if someone should shed some light on this for me please?

When I tune the RSP2 to 446 Mhz which is PMR I get this on the waterfall / spectrum:



and I am unable to actually pick anything up. When I put my Uniden 125XLT on the antenna (Discone, Diamond D3000) it always picks up PMR straight away (assuming there are broadcasts, obviously).

I seem to remember with an old RTLSDR dongle I had similar results with SDR Sharp so is it a computer thing? The RSP is well away from the computer and I don't see this kind of interference (or whatever) with anything else.

Thanks for any help!

[mark.]

Was there a broadcast playing at the time of your snapshot? Do those lines show up under all RF and I.F. gain settings?

[MajicM]

No broadcast I was aware of, it appears like that all the time.

[g1hbe]

That's strange - I find my RSP2 very sensitive on 446 and I hear lots of activity. Those spikes don't look right though - does your USB lead have ferrites on both ends? Try re-arranging your leads to see if you can get rid of that noise. Reduce that 'gain reduction' setting as well, see if signals emerge from the noise floor.

[MajicM]

I don't think it does, I'll check. It's never been an issue for anything else.

I can always buy another extender if needs be, it wasn't a cheapie one I know that much.

Ah, so gain could be playing a part here, I'll have a play with that too.

Thanks for the advice