"There was mention of putting a 1N4148 across the choke but was
confusing as to which way to mount it"
David-- Cathode towards Vcc!
Paul -- AI7JR
On 9/2/23 16:11, David R. Hassall
WA5DJJ wrote:
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Dear Group,
I am just finishing up 5 QDX's ..... 3 Rev 3's and 2 Rev 5's.???
I have been trying to follow this thread but it is a little
confusing as to what modifications really help prevent
destruction of the PA transistors and what parts to use
one should use.... There was mention of putting a 1N4148 across
the choke but was confusing as to which way to mount it and
something about using a power supply at 12V @1 amp.?? There
there was two or three messages that put two diodes (zenners or
TVS???)and one had them hooked to a different spot than the
others.?? Since, I am a careful sort, who follows Hans Summers
instructions to the limit.? But I have also had BS170 FETs fail,
I would like to give my 5 QDX's at least a fighting chance of
survival,? I would really like to see a message from some one
that explains what to do and what to use with part numbers to I
can keep all my new QDX's running for a long time.? At least as
good as my original version 1 which is still going strong after
a couple of final transistor failures and an IC5 failure.??
Hope everyone has a great week.?? If anyone needs any 0805 47uH
inductors like L11, I will have 200 of them after September 15
and will gladly share.?
Take care and have fun.
Dave WA5DJJ
SUPER QRSS/WSPR GRABBER
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