[DSP-10] CW transmit has a raspy sound

[Lee Scott - AA1YN]

Just a note to let others, esp Ron, know what I've found so far. I've been 
talking with Mike, KD7TS off reflector so:

while everything might not be solved, I did make some good progress this 
AM.  One thing I noticed when turning on the power while monitoring the +5v 
to the PLL circuit, about a 120Hz signal (not quite sync'd to AC line) was 
present. After tracing it for a while, I realized this noise was coming 
from the lock detect circuit so when I booted up the receiver, the noise 
went away. - so much for that.  Anyway, while doing some further scoping, I 
remembered about a jumper from the output of U8 feeding the 19.68Mhz signal 
back to the PLL.  Not knowing what else to do, I decided to replace this 
jumper with a piece of coax as I have some 0.070 dia Teflon coax.  I took 
some more measurements and much of the problem appears to be solved.  I did 
a screen capture prior to the mod in LTI mode with a signal generated by my 
FT817. (This eliminates the PC sound card question).  I then replaced the 
jumper (W12) with the coax and did another screen capture.  I also did a 
couple of recordings with the FT817/PC.

The URL is http://www.aa1yn.com/dsp-10/wav/ with the links to the latest at 
the bottom.

I will try do do some more testing tomorrow including some on air testing.


Lee Scott - AA1YN http://www.aa1yn.com
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Hooksett, NH
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