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Eico HF-89a question


2010-01-28 10:39 am
Eico HF-89A question. Does someone have a schematic of the Eico HF-89a? My specific need is to know the value and location the low value capacitor that is attatched to the grid of V 2 and V 3. What is the location of the other end of this capacitor and the value?


2010-01-28 10:39 am
Yes, but ----

Sorry, I am not asking about the 0.25 mf capacitor.
The capacitor I am asking about is a change brought
about when EICO changed vendors of the output
transformer. The HF-87 and first version of the HF-89
had a 750uuf placed across one half of the transformer
primary to deal with phase shift in the transformer. This
capacitor was replaced in the HF-89a. According to
old posts in the EICO Yahoo group. The new "fix" was
a "low value capacitor at the input of the 6SN7. The
amp I recently purchased does not have this capacitor
but I think I can see where it was cut off of pins 1
of each 6SN7. If someone has a 89A schematic, I
need to know the value and location of this capacitor.
Again, I am not asking about the 0.25 mf capacitor you
describe. I feel the cap. would somehow be connected
to pin four or five of V4 and V5. Thanks for your help.