Hi,
three years ago I built my Stereomour, Nov 2011. Worked great right from the start. Voltages and resistances measured fine, everything sounded beautiful.
This morning the right channel started going in and out, and now it is mostly out.
I measured the resistances, and they are all close to perfect.
Voltage measurements are not all perfect.
A1-A4 measures 2.0 VAC (Should be 2.5 VAC)
** C1-C4 measures 1.5 VAC (Should be 2.5 VAC) **
Mains measures 227 VAC, which is close enough to the advertised 230 VAC.
pin 1 measures 347 VDC (should be 350)
** pin 2 measures 124 VDC (should be 230) **
pin 5,11 measures 55 VDC (should be 60 VDC)
pin 15 measures 347 VDC (should be 350 VDC)
** pin 14 measures 190 VDC (should be 230 VDC) **
pin 16 measures 55 VDC (should be 60 VDC)
pin 17,18 measure 373 VDC (should be 380 VDC)
pin 20 measures 55 VDC (should be 60 VDC)
A1,A2,A3, A4 are 56, 346, 0, 56 VDC, which is close to 60,350,0,50 VDC
C1,C2,C3, C4 are 55, 346, 0, 56 VDC, which is close to 60,350,0,50 VDC
IA measures 373 VDC (Should be 380 VDC)
IB measures 373 VDC (Should be 380 VDC)
** OA measures 121 VDC (should be 230 VDC) **
** OB measures 190 VDC (should be 230 VDC) **
Kreg measures 2.5 VDC
-reg measures 0 VDC
So the AC of both tubes (A1/A4 and C1/C4) is off, especially the C tube
Also the DC voltage on pin 2 is way off, 124 instead of 230
Pin 14 is also not OK, 190 instead of 230
The Active Load PC board is also not OK
OA being 121 instead of 230
OB 190 instead of 230
All LEDs are fine.
Can you please help? Is one of the transistors on the Active Load board dying, or both?
Thanks a lot,
Aske
