ARC SP8 too much Gain!
Wow, thanks for the quick responses!!
Brett - I have only a schematic and a parts list. The board is not
marked with component positions.
I'm in the UK so a call to ARC would be a little pricey. Their
website says there is no public email access at the moment either!
Patrick - On the schematic, resistor 28 and 29 are bottom right - to
the left of the manual mute switch (28 is above 29 - both rated at
39.2K 1%) and it says 'see note 2'. The notes are directly below
the symbol for R29. Note 2 says 'Add R28 39.2k to cut gain 6 dB'
The right hand side of these resistors leads up to a group of 4
capacitors and the left hand side runs up to the line that goes
between a 1.28k resistor and tube no. 4 .
I'm afraid that the thing I just spotted flying over my head must have
been your explanation! (as I said, I'm an electronics virgin!!
NFB - Negative feedback?
On my diagram R27 that you mention is a 33k value.
Cheers
Chris
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