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N_Cook

On 05/11/2016 12:11, wrote:
On Friday, November 4, 2016 at 2:49:16 PM UTC-4, N_Cook wrote:

Its not a tolerance thing, gold fourth band.
R67 and R66 are exactly the same resistor batch, the green of the heat
aged one is now not green, its value is now not 150R

You miss my point. Resistors drift, true. And the resistors in place seem to be undersized (operative word "seem") You intend to to replace them with higher-watt devices that are at the correct value. All good, so far.

But, I am asking whether the circuit itself may be tolerant of that drift - hence the question on band 4 - if any.

Peter Wieck
Melrose Park, PA

The schematic for seemingly all these amps , minor variations, is on
Electrotanya as Parsek Mark Bass Little
not all the fan current goes through this R67 and without measuring some
actual circuit nodes on this amp and modelling the schematic I don't
know how much current is actually now or should be taken by the MJE340,
but something is not hunkey dorey.
Note the refs to 2W and 5W on that schematic,R67 and R67, in reality
exactly the same size , colour body , shape on this amp