[hpsdr] Penny PTT unkeying spike - T/R sequencing?

[John Petrich]

Phil,
	
Thanks a million for the expert input.  Had been wondering what was going
on.  Still not sure what the exact issue is, but I'm satisfied with 'it's in
the software'.  Does cause me to wonder what proportion of those  hams who
actually use their HPSDR rigs on the air are unwittingly  transmitting
spurious signals.   Running my <PA menu> settings at "39.2" seems like a
safe setting in my lab. 

Will look forward to the revised software, and for Pennylane (for other
reasons).  

Regards,

John, W7FU

-----Original Message-----
From: Phil Harman [mailto:phil at pharman.org] 
Sent: Wednesday, February 02, 2011 5:32 PM
To: John Petrich
Cc: hpsdr at openhpsdr.org
Subject: Re: [hpsdr] Penny PTT unkeying spike - T/R sequencing?

Hi John,

This is a problem in PowerSDR which we found whilst testing PennyLane.

For now do not reduce the Gain per Band to below 40.9bB.  Below this
PowerSDR can send I&Q levels that exceed the 16 bit range of values we can
accept. This mostly happens with the CMPDR on.

Bill, KD5TFD, has fixed this and it will be included in his next release as
will Doug, W5WC, next version.

73 Phil...VK6APH




> ***** High Performance Software Defined Radio Discussion List *****
>
> Tom,
>
>
>
> I feel your pain.  My HPSDR transceiver has been on the air for over 1 
> year now, with none of the problems that you have experienced.  That 
> said, I'd like to offer an observation of an anomaly with my Penelope 
> that may add to your thinking about your problem.
>
>
>
> If the drive in the <PA menu> is set to the "38" value, while in the 
> key down, steady state, CW mode, significant picket fence spurs  start 
> 2 KHz either side of the carrier.  The initial spur is down about -40 
> dBc.  The remainder of the spurs diminish and vanish about 20 KHz 
> either side of the carrier.  If the drive in the <PA menu> is reduced 
> to "39" or greater there are no spurs to detectable to -100 dBc.  The 
> Penelope output amplifier has been replaced with no change in this 
> anomaly.
>
>
>
> Regards,
>
> John Petrich, W7FU
>
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