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<DIV>Hi Ken</DIV>
<DIV> </DIV>
<DIV>Thanks for the update on the SB200 work.</DIV>
<DIV> </DIV>
<DIV>I am in the final throes of refurbishing an SB-101 to which I had
previously added top band. </DIV>
<DIV> </DIV>
<DIV>Had to change about 30% of the half watt carbon resistors which had all
aged high and well out of spec. </DIV>
<DIV> </DIV>
<DIV>The LMO switch needed a good clean and I found a leaky 6AU6 at V3 which had
a major effect on Rx AGC. Substituted an IEC type which works fine.</DIV>
<DIV> </DIV>
<DIV>Changed the Rx RF stage to a 6HS6 which increased the sensitivity somewhat
but not surprised as the slope is almost twice that of the 6AU6 - will not
help with the dynamic range though as 40m is very busy in the evenings with
large BC signals. The heaters also needed re-balancing as the 6HS6 takes
450mA which is 150mA more than the 6AU6.</DIV>
<DIV> </DIV>
<DIV>The S meter zero preset pot also needed changing and the PA neutralising
adjusting.</DIV>
<DIV> </DIV>
<DIV>Works much better and gives 100W plus on all bands except 10m where it
is about 90W. Now I just have to find a replacement bandwidth knob, box it
up and move on to the next project.</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>