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<DIV>Hi Sandy</DIV>
<DIV> </DIV>
<DIV>My SB104A that I recently sold had a conventional VFO and frequency counter
to display the operational frequency. I suspect that your frequency
jumping is either a problem in the slow motion drive mechanism or the
lubrication in the VFO tuning capacitor sliding contacts has dried out - the
latter is a well known problem in earlier valve SB-Line models (which run a lot
warmer than the '104A). Also, take a look to ensure that the grub screws and
fixings have not come loose in the drive mechanism or VFO mountings.</DIV>
<DIV> </DIV>
<DIV>Another quick test is to spray a little switch cleaner lubricant onto the
sliding contacts and bearings of the VFO tuning capacitor and see if that
fixes the problem in the short term - use it sparingly though. If that
works you may have to clean and re-lubricate the capacitor contacts and bearings
but well worth the effort.</DIV>
<DIV> </DIV>
<DIV>While you have the VFO open, check that the sliding contact springs have
some tension by pressing gently down to feel the tension and see that
they return to their original position.</DIV>
<DIV> </DIV>
<DIV>I have seen recommendations to solder a piece of braiding between the rotor
and the body of the tuning capacitor on some SB models but I have never had to
do that.</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>