[hpsdr] Distorted audio

[Jeremy McDermond]

On Aug 9, 2011, at 11:51 AM, Chris Smith wrote:

> ***** High Performance Software Defined Radio Discussion List *****
> 
> Hmmm...  I've just turned on my HPSDR kit for the 1st time in about a month and was horrified to hear a very distorted audio output. CW signals sound like T4/5 report.
> 
> I haven't yet 'scoped the 13.8V line or the various O/Ps from LPU but everything seems to be working except Excalibur has lost phase lock with the Trimble Thunderbolt reference and no amount of tweaking the trimmer on X1 will pull it back into lock.

I had the TCXO go out on my Excalibur causing it not to be able to correctly lock up.  It caused a persistent warble in the signal because Mercury was valiantly trying to phase lock to the 10MHz signal.  You might try taking out Excalibur and using Mercury as your clock source and see what happens.

My understanding is, though, that Excalibur doesn't phase lock your external clock to the X1 oscillator.  The jumper chooses either one or the other, processes it into a square wave, and puts it on the Atlas bus C16.  The LEDs merely indicate the difference between the external input and the internal oscillator.

> Any ideas?
> 
> Chris G4NUX

--
Jeremy McDermond (NH6Z)
Xenotropic Systems
mcdermj at xenotropic.com




 1312942639.0