From: John Wagner (firstname.lastname@example.org)
I was lucky enough to remember that a QRP Homebrewer I previously read
had an article about capacitors by Paul Harden, NA5N. This is the
Winter, 2000 edition of that journal.
In that article, Paul states that the difference between Ceramic and NPO
Ceramics are that the NPO's have a stable temperature coefficient. He
says that non-NPO caps should be avoided in frequency determining
circuits (like VFO's).
In the VFO that I'm building for the MH101 project, I *think* I may have
used two non-NPO caps for C4 and C8 in the VFO. I'm finding it difficult
to ID what type these caps are. From the descriptions in Paul's article,
they appear to be either Monolithic Ceramic Caps or Polyester Film caps.
In the picture at: http://www.qsl.net/kb1ens/sw30/1231_004.jpg - they
are the two yellow capacitors on the board. They are marked 121 CIE and
332 AIJ. Using the tables on pg 62 and 63 of the article, I can't find
anything about the CIE or AIJ markings on these caps.
Can someone kindly ID these caps for me?
More importantly, are they OK to use in the VFO of the radio? I'm at the
point now where they can be easily replaced.
Thanks es 73,
-- John Wagner - email@example.com Web page: http://www.neknetwork.com
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