KPA 100 Resistance Checks

[Chuck Gehring]

I am building the KPA 100.  I have just tried the resistance measurements on
page 41 of the Alignment and Installation.  The resistance measurements for
the Q1 and Q2 collectors  will flash 11 or 12K ohms then jump down to -6.5K
ohms and then count up to -3.5K and then stabilize.  When I first checked
the J3 red terminal it responded normally in about 20 seconds showing
greater than 10 K ohms.  Now even that is giving me inconsistent readings.
The remainder of the readings in that table for the KPA 100 test points are
okay.  I saw a similar post in the archives from Dec 2004 but the thread
ended without a response.

Comments Recommendations would be appreciated

73, KI4DGH

Chuck Gehring

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[Ward Willats-3]

>I am building the KPA 100.  I have just tried the resistance measurements on
>page 41 of the Alignment and Installation.

Sounds like you are maybe running into the photoelectric effect on
the PA transistors too. Do you have a strong light on the workbench?

http://www.ac6rm.net/mailarchive/html/elecraft-list/2003-11/msg00574.html


-- Ward / KG6HAF
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