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Suggestion: better volume control when using the M0PUB AGC

Open arodland opened this issue 3 years ago • 2 comments

The new slow AGC algorithm already uses a multiply, so how about, if it's active, make the AGC threshold a function of volume and skip the right-shift volume control (which sounds like crud at any setting below 8). There should be no CPU penalty — the thresholds can be in a PROGMEM lookup table (just 52 bytes or so) and eliminating the right-shift should about make up for the cost of fetching them to register.

I'd try it myself and send a PR, but I'm more of a software guy than a hardware guy; I bought an eBay unit and I haven't gotten it disassembled far enough to get at the ISP connector yet :)

arodland avatar Oct 14 '21 01:10 arodland

Think this is a great suggestion. Making AGC threshold a function of volume could simplify things for SSB/CW. Then volume control becomes basically an attenuation control (like ATT2) and this may reduce potential overloads further-on in the DSP processing chain (in the presence of strong signal). Will need to look into this to see if this is really possible.

Regarding ISP programming an eBay unit, Scott figured out how to: https://groups.io/g/ucx/message/10339 Thanks!

threeme3 avatar Oct 14 '21 08:10 threeme3

That's a different unit than I have, but appreciated anyhow!

arodland avatar Oct 14 '21 13:10 arodland