It's all about the Software

Hi Simon,

I've been playing with DSDplus and have noticed that I have to use W-FM instead of N-FM in order to decode DMR transmissions.
W-FM works (with some sync errors), N-FM never syncs.

I have a question on the horizontal bar graph showing audio levels in the Receive DSP panel. What do the two bars indicate?
One is signal, the other is? Also, switching from N-FM to W-FM causes the bars to go red (I must be over driving something).

See attached. Note: the two screenshots show idle time between transmissions.

Hi Barry

See here for NFM versus WFM with DSD+:

https://www.sdr-radio.com/dsdplus

Seems is the need to have no de-emphasis or filters etc. WFM is "clean", so to speak. I believe it is similar issue in other software like SDR#:

73

Max

Thanks Max,

I don't know how I missed that.

I see Simon explains that the volume widget is Red when above 95%.

https://www.sdr-radio.com/receive-dsp

Still haven't found out why there are two bars.

Barry
WB2ZXJ

No idea on that Barry, but as it's flat out red when there is wide spectrum white noise, and it does not vary according to setting of the audio level control I imagine it's some visual indication of the audio signal to noise ratio on the input to the audio chain in the presence of a signal? Just a guess though.

Hopefully Simon will illuminate us if he happens to read this post!

73

Max