SDRplay Community Forum

Is there a SPDPlay Device Controller for Dummies, like if in shortwave you set it to this, VHF you set it to that and so on. I am monitoring around 138 to 143 NFM P25 Phase 1 Transmissions. So any help would be grateful.

Hi
In fact what you are asking for is hard to do.
Soft ware Defined Radios are mainly limited by what you run the software on .
On the SDR hardware side basic rules of radio applies:
Use an antenna as suited to what you want to receive as possible.
Use as little amplification as possible
Use as little bandwith (sampling rate ) as needed.
I don't know what "NFM P25 Phase 1 Transmissions" are may be satellites meteo ?
138 to 143 MHZ is rather clear from strong signals here but a front end filter is always a good idea.
Satellites transmissions are always rather weak and terrestrial interference can be very strong.

Not a recommendation as such - but try the following for VHF

LNA gr = 59dB
AGC off
Overall gain reduction 57dB
Leave the ADC set point at -15dB

This will force the low noise amp at the front end - the one inside the mirics chip - on. If LNA gr is less than overall gr - the LNA chip is off. If you don't n=have an antenna pre-amp you will lose s/n ratio with LNA off. The LNA chip between the antenna input and the front end filters is on all the time above 60 MHz.

If you have a high gain pre-amp then run with the LNA gr set to keep the LNA off - it will make no difference to the s/n ratio.

It may be easiest to play about with settings whilst tuned to a weak WFM broadcast station. If satellite work on 138-143 is important you might also consider fitting a filter to block FM signals to avoid breakthrough.

Rgds

David

Thank you for all the good information