Recent content by Cordwangle

Checked bias current on my dc-3 (DC23B/1993) recently, using o/p transformer resistance method, as I felt that it was running hot (no red plating tho'). One side (pair of el84s) was pulling 40.1mA (393Vdc on plate) & other side 48.0mA (392Vdc on plate); this is at a bias voltage of -10.7vdc. I...

Hello - just a thought: check mains transformer has all secondary connections made; sounds crazy but I worked on a studio 22 & all dc voltages across the board were low...! Took me a while but traced problem back to mains tx which had one of the red, sec leads blanked off (on cct diagram it's...