You need to give the circuit board designations when referring to components.
If you're referring to D243/253, the diode is likely a MMSZ5250B.
If you're referring to D243/253, the diode is likely a MMSZ5250B.
Yes the diode is D253.
Still no oscillations. R178 keeps burning. Anybody have the schematics to share?
I dont know why there is cap 220uf in place R143.
Still no oscillations. R178 keeps burning. Anybody have the schematics to share?
I dont know why there is cap 220uf in place R143.
You'll have to follow the circuit from both ends of R178 to see if anything connected to it is shorted.
In the photos I have, R143 is a 100 ohm resistor.
In the photos I have, R143 is a 100 ohm resistor.
Found one opamp short. Replaced still no oscillations. What is FET471 and FET260.
FET260 getting hot.
FET471 has oscillations on gate.
FET260 no oscillations.
FET260 getting hot.
FET471 has oscillations on gate.
FET260 no oscillations.
FET 260 is the low-side optocoupler regulator.
FET471 is the driver for the low voltage transformer in front of it. It should have oscillation on the gate and drain.
Both of these will get hot and fail if not clamped to the heatsink.
FET471 is the driver for the low voltage transformer in front of it. It should have oscillation on the gate and drain.
Both of these will get hot and fail if not clamped to the heatsink.
There are many "missing" components in MTX amplifiers, same board used on different amplifiers. When first looking at one I did the same and thought I was missing components entirely.
In the photos I have, there are no caps in C243 or C253 for the 1000. In other similar amps, the locations have caps but they vary in value.