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<DIV>Hi Ron</DIV>
<DIV> </DIV>
<DIV>I have now had a chance to study the circuit diagram for the SG-7 in
detail:</DIV>
<DIV> </DIV>
<DIV>1. The HT electrolytic smoothing capacitors are 20uF 150V so the 600v
working potential that you mentioned is way over what is actually required. The
anodes of the two valves are shown as having 60-80V potentials on them but this
will be higher when first switched on and the valves not conducting any anode
current. The two capacitors across the mains supply should certainly be
adequately rated for AC working and allowing for additional spikes.</DIV>
<DIV> </DIV>
<DIV>2. As already stated by another contributor MMF is the old fashioned way of
stating pF - the original designation stood for micro micro farad.</DIV>
<DIV> </DIV>
<DIV>3. Decoupling capacitors in the RF oscillator can be disc ceramic types but
the tuning capacitors in the AF oscillator should be film types.</DIV>
<DIV> </DIV>
<DIV>4. Any fixed tuning capacitors in the RF oscillator could be NPO disc
ceramic types although my preference would be for silver mica. The photo of the
coil pack in my copy of the manual is not very clear.</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><BR>Follow G3OOU as
@BobFBurns on Twitter </FONT><FONT lang=0 color=#0000ff size=2
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