[Elecraft] KRC2 Troubleshooting

[Brian F. Wruble]

I have completed my KRC2 to the point of the smoke test.  No smoke ... I
guess that is good.

When I power up, the LED lights (low), but no "short delay while the KRC2
performs diagnostics."

The first test step, "Holding F1" , fails to produce 12 volts at the 60M
source, or at any of ther terminals.

I have done about 2 hours of visual inspection.  Every diode is correctly
oriented, as are all the ICs and the electrolytics.

I am beginning to wonder if I have the voltage regulator in backward,
though it looks exactly right.

TGhe schematic says I should have +5 volts at C14 and +12 V at C13.  I have
the reverse.  Before I try to unsolder U3, can someone confirm that those 2
caps are correctly labeled on the schematic?

Also can someone describe the pin numbering for U3.  It really looks like
it is in there correctly.

Also, the +5V end of D8 reads +5V (which should be right), but the -12V end
of R12 is only -10.4V.

Do these clues suggest anything?

Tnx.  73 de Brian W3BW


*Brian F. Wruble, C.F.A.

*70 is the new 40.*
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