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<DIV>Hi Ken</DIV>
<DIV> </DIV>
<DIV>I have now tracked down the problem with a slow transition to transmit on
CW which was due to a previous owner changing the Vox timing capacitor C213 to
1uF instead of the correct value of 0.22uF but using a capacitor almost
identical mechanically to the correct type. Having replaced the capacitor it now
works correctly, the relay driver anode voltage drops from 300V to 90V in about
10mS and the first dit can be seen in the RF output.</DIV>
<DIV> </DIV>
<DIV>During the investigation I noticed that the anode waveform of V17a is
considerably distorted. This is probably due to reducing the value of R328
from 470K in order to increase the keyed sidetone signal into the Vox amplifier
and detector. I will try reversing out that change.</DIV>
<DIV> </DIV>
<DIV><FONT lang=0 size=2 face=Arial FAMILY="SANSSERIF"
PTSIZE="10">73<BR></FONT><FONT lang=0 color=#0000ff size=4 face=Arial
FAMILY="SANSSERIF" PTSIZE="14"><I><BR>Bob</FONT><FONT lang=0 color=#000000
size=2 face=Arial FAMILY="SANSSERIF" PTSIZE="10"></I><BR>Bob F Burns<BR>C Eng,
FIET, MSE<BR>Amateur Radio Callsign: G3OOU<BR>Registered RSGB
Instructor<BR>G-QRP Member No: 6907; Zone: 14, QRA: IO91WH; WAB:
TQ25<BR>Secretary of Crystal Palace Radio & Electronics Club: <A
href="http://www.g3oou.co.uk/">www.g3oou.co.uk</A><BR>Technical web site: <A
href="http://www.qsl.net/g3oou">www.qsl.net/g3oou</A></FONT></DIV></FONT></BODY></HTML>