Me neither. Do you spot any differences between the two channels in part values or heatsinking? All I can imagine is that for some reason ventilation may be worse for the left channel and this was a bodge to stop things from overheating. Or if the bias has a negative TC, maybe it's the right channel that's the problematic one.
That's an odd one for sure.
That's an odd one for sure.
The manual tell you to measure the voltage, but it show you currents values, so that there is mistake in the values
Ah yes was thinking that might be the case, i did not notice any difference between the two sides, so 10mV for both test points it is then, thanks for clearing that up. I left them at 10mA each for the time being, as I found it strange alright. They were quite a bit out, more in the 30mV range, but the DC bias was well out too, might not have been serviced since the 70s !
I stripped it apart, inspected solder joints under magnification, cleaned all switches with super 10, set dc offset and bias, replaced 4 x 1uf audio coupling caps as ESR was about 4.4ohms a bit high all the rest measure really good. Thanks for your help
I stripped it apart, inspected solder joints under magnification, cleaned all switches with super 10, set dc offset and bias, replaced 4 x 1uf audio coupling caps as ESR was about 4.4ohms a bit high all the rest measure really good. Thanks for your help