Hello. Can anyone help with the burning resistor?
Realistic SA-2000 amplifier. The problem is with the resistor R 625b
I changed it for a new one, but it burned out immediately..
R 625b is in the Meter Circut, in the diagram page 30 in the upper right corner.
I checked the diodes D605, D607, D609, D611.
Variable resistors VR601a and VR601b have almost identical resistances.
Then I checked all the other diodes on the pcb.
I changed to new electrolytes C615, C602, C603, C802, C801.
After switching on for a while through a light bulb connected in series, the resistor still smokes.
What could be the cause of burning resistor R 625b?
There is one more problem with this amplifier. In the diagram, resistor R625a and b have values of 27k. In fact, they are 100 ohm metallised 1W resistors. The PCB doesn't look soldered here. All solder pads looks as from the factory. The values of few other elements are also different between the schematic and reality. I searched the web for information on this subject, but found nothing on the Internet.
Realistic SA-2000 amplifier. The problem is with the resistor R 625b
I changed it for a new one, but it burned out immediately..
R 625b is in the Meter Circut, in the diagram page 30 in the upper right corner.
I checked the diodes D605, D607, D609, D611.
Variable resistors VR601a and VR601b have almost identical resistances.
Then I checked all the other diodes on the pcb.
I changed to new electrolytes C615, C602, C603, C802, C801.
After switching on for a while through a light bulb connected in series, the resistor still smokes.
What could be the cause of burning resistor R 625b?
There is one more problem with this amplifier. In the diagram, resistor R625a and b have values of 27k. In fact, they are 100 ohm metallised 1W resistors. The PCB doesn't look soldered here. All solder pads looks as from the factory. The values of few other elements are also different between the schematic and reality. I searched the web for information on this subject, but found nothing on the Internet.
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