Re: S-85 refurbish: I've got a problem during the RF alignment of bands 1 and 2 - trimcaps don't peak!
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Maynard,? good to know that they show a gimmick like this 
But that leaves the that ongoing v1-v2 coupling question ?more mysterious. ?
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From: [email protected] [mailto:[email protected]] On Behalf Of Maynard Wright via groups.io
Sent: Saturday, February 15, 2025 11:57 AM
To: [email protected]
Subject: Re: [HallicraftersRadios] S-85 refurbish: I've got a problem during the RF alignment of bands 1 and 2 - trimcaps don't peak!? Hi, Emanuele,
There is a gimmick in the S-85 schematic and parts list, C38, that has a
capacitance of 2 mmfd (pF). It should, ideally, be a twisted assembly
just about 10 percent shorter than is required to emulate C62 in the
S-40B if you want to check what a gimmick of about the right size ought
to look like.
C38 couples the CW oscillator signal from the junction of pin 3 of V5
(6SC7), R29, and C55 to pin 4 of V4 (6SK7).
The S-40B also uses C38, specified in the S-40B parts list as 2 mmf but
labeled on the schematic with "1," implying 1 pF.
Incidentally, Note 2 in the S-85 schematic states that all capacitor
values are in "MMF" unless otherwise specified. In the parts list, C38
and others are specified in "mmfd." The S-40B parts list uses "mmf" and
"mfd."
73,
Maynard
W6PAP -- don??? va3drl
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don Root