Squelch scale
Squelch scale
The "100%" setting of the squelch scale is quite low compared to where the noise floor can be. On my RSP1A, with a gain setting of 5, IF gain at -35 and AGC off, on VHF and UHF the noise floor is around -80 dBm, which seems to correspond to around 90% of the squelch level. Sometimes it can be above 100% in which case I have to use the Visual Gain setting to artificially lower the noise floor. I don't want to have to do that, especially since Visual Gain is not a setting that can be stored within a favourite. Also it would be nice to have a squelch level indicator on the spectrum display in the form of a horizontal line (that could be enabled or disabled in settings or the View tab).
- Simon G4ELI
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- Joined: Thu Aug 06, 2020 7:27 am
- Location: Mawnan Smith
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Re: Squelch scale
Please add a full screenshot so I can see your RSP1A in action. 80% seems to be very high.
Re: Squelch scale
Here is a screenshot with squelch set at 82% - the setting is low enough for the squelch to turn off:

And here is one with the squelch setting increased to 87% so it works properly:

With AGC on (I need it on sometimes because signal levels vary a lot) it's even worse - gets triggered at 93%:

At certain bands with certain antennas it goes over 100% - with a gain setting that I have observed the best S/N ratio at - which is usually 5 to 7.

And here is one with the squelch setting increased to 87% so it works properly:

With AGC on (I need it on sometimes because signal levels vary a lot) it's even worse - gets triggered at 93%:

At certain bands with certain antennas it goes over 100% - with a gain setting that I have observed the best S/N ratio at - which is usually 5 to 7.
- Simon G4ELI
- Posts: 2166
- Joined: Thu Aug 06, 2020 7:27 am
- Location: Mawnan Smith
- Contact:
Re: Squelch scale
The signal levels are very high - do you have a pre-amp?
Re: Squelch scale
No, in this case it was just an RH-660S antenna connected straight to the SDR with a right angle connector. The SDR was connected to the computer via 3m long good quality shielded cable with ferrites at both ends, 1 full turn of cable (so it passes through the ferrite twice) on each.
Re: Squelch scale
Same here on VHF/UHF with my RSP2 and broadband antenna and lots of man made noise ... but when you keep RF Gain as low as possible and lower Visual Gain a bit then the squelsh range is good. 73, Leongoscickiw wrote: Fri Dec 18, 2020 6:55 am No, in this case it was just an RH-660S antenna connected straight to the SDR with a right angle connector. The SDR was connected to the computer via 3m long good quality shielded cable with ferrites at both ends, 1 full turn of cable (so it passes through the ferrite twice) on each.