Fender Transformer Codes
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Fender Transformer Codes
From BREME–(at)–sn.com Sat Jan 13 19:10:03 CST 1996
Article: 77538 of rec.music.makers.guitar
From: BREME–(at)–sn.com (THOMAS BREMER)
Subject: RE: Silverface Deluxe Rev Questions
Date: 13 Jan 96 08:35:11 -0800
Organization: The Microsoft Network (msn.com)
Heres a quick way to date Fender amps (’60-82). View the underside of
the chassis (flashlight helps alot)look for the reverb driver trans.
Its in the middle of the 6 preamp tubes with the removable shields.
You’ll find 2 rows of numbers, top set is the Fender part #, always
starts with a 022, in this case it would be 022921. The bottom set is
the date code. Works as follows, they have 6 numbers, first three is
the EIA manufacturer, ignore this. The last three tell you the year
and week. Example-606423. For a black face, this transformer would
have been made in 1964 during the 23 week (—423) The trick to this
is they don’t renumber the decades. A silverface made on the 23rd
week of 1974 will have the same date code. The only good thing about
dating amps this way is Fender never deviated-still valid today. I
use this before buying a amp always-check all four transformers-will
tell you if there has been problems along the way. Very rare to find
different year trans. in any Fender products.
If your JBL says D120F on it(look for the “f”) certainly could have
been stock. On the bottom lower corner of the grill cloth was/is a
1×2 inch “JBL” plastic logo that Fender attached. By 1968 deluxes
usually left with CTS/EMINANCE speakers (Jensen had closed down) Once
in awhile you can see the EIA code, CTS-starts with a #137-sometimes
these are under the doughnut fender speaker label. Dating system for
transformers works on the speakers also.
Fender used two kinds of silver/blue grill cloth, first version, as
with your amp, the blue stripe fades away to red, then brown and
eventually disappears. The last version had a super bright neon blue
which held its tint. Remember that Fender dealers could order any of
the silverface amps with black faceplates and regular 60’s silver
grill. ($50.00 additional at that time) Always pull on the volume
controls to see if they pull out-these were pull boosts, not labeled
on 70’s faceplates.