[hpsdr] Warbling audio on Tx.

[Paul Fletcher]

I have noticed something similar in tune - if I hit tune in a CW mode the 
power out is rock steady. If I do the same in other modes power out 
fluctuates quite rapidly. I've been too busy to look into this in detail. 
That being said I have used the rig on 40M SSB and got very good audio 
reports so I just put it down to the carrier generation in tune mode. I was 
also using Pennywhistle.

That was using v1.19.3.5 of PowerSDR and the V2.9/V1.4 firmware combination.

Regards,
Paul M1PAF

----- Original Message ----- 
From: "Chris Smith" <chris at vspl.co.uk>
To: "HPSDR list" <hpsdr at lists.openhpsdr.org>
Sent: Wednesday, September 28, 2011 8:57 AM
Subject: [hpsdr] Warbling audio on Tx.


> ***** High Performance Software Defined Radio Discussion List *****
>
> Hi
>
> I paused briefly in my toil with my PA yesterday to try a brief contact on 
> 40M. Before sending in anger I had tried transmitting into a dummy load 
> and listening to the audio in MON mode. All had sounded OK so I answered a 
> CQ but was told, by the other station, that my audio was almost 
> unintelligible because of a warble. I ended the contact and said 73 which 
> the other station said was the only part he had been able to hear 
> properly.
>
> I did a few more tests into the dummy load including the 2-tone test at 
> full o/p of Pennywhistle. I noticed that during this test my power meter 
> showed that the o/p power dropped momentarily several times during the 10 
> seconds that I continued the test - sometimes 3-4 times per second. At the 
> same time as these drops in o/p power occurred the current drawn by the 
> rig also fell.
>
> I haven't tried the same test without Pennywhistle in the path so I don't 
> know if the problem lies with PW or elsewhere.
>
> I'm at a loss to understand what is happening. The average CPU usage 
> varies between (approx) 16% & upper 30s% and I very occasionally (rarely) 
> get  a momentary drop out of audio on Rx but nothing like the frequency of 
> power drop on Tx. I'm using an Intel Atom board (1.6GHz) to run PSDR but 
> have a much more powerful set-up available if that should prove necessary 
> (Core 2 Quad at 2.4GHz (Q6600)).
>
> Set up:
>
> Metis @ 1.5
> Pennylane @ 1.5
> Mercury @ 3.0
> Pennywhistle
> Alex
> PowerSDR KD5TFD 2feb2011b 1.10.4+
> WinXP SP2
>
> Any ideas gratefully received.
>
> Cheers & 73
>
> Chris G4NUX
> _______________________________________________
> HPSDR Discussion List
> To post msg: hpsdr at openhpsdr.org
> Subscription help: 
> http://lists.openhpsdr.org/listinfo.cgi/hpsdr-openhpsdr.org
> HPSDR web page: http://openhpsdr.org
> Archives: http://lists.openhpsdr.org/pipermail/hpsdr-openhpsdr.org/
> 


 1317201783.0