R3 on the Stereo Simul Class 295 amp board.

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Jun 28, 2024
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Howdy All,
I'm curious about the R3 ghost resistor on the Stereo Simul Class 285 amp power supply board.

On an amp I sold this resistor is not present. The schematic shows this resistor as deleted on this model My question relates to why the schematic is drawn this way. It looks like the resistor is physically clipped from the board. I read there is a 290 model amp that is similar but one of them has a hotter bias. Could the R3 resistor be present on models similar to the 295 to change the bias slightly? It is deleted from the 295 board for a little hotter bias? Could the R3 resistor(s) be for export models? I'm noticing other 295's that I can get chassis pics of do not have the R3 resistor Thanks


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Without looking at the full schematic, those resistors tied in with 100V electrolytic caps would lead me to think they're definitely setting the -VDC bias of the output tubes. It could be that the board is used in various models , or a mid-production design change.

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