I can double check when I get home tonight but if I remember correctly from last week it think I was only getting about 12V.
Is the switching power supply operating?
Please (and this applies to anyone who needs repair help) use your sig line to list all equipment you have, editing it as equipment changes. Include the model numbers. If you can't do this due to being a new member, make a list in the next post.
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Oscilloscope (yes or no)
Multimeter(s)
Type of signal source (grounded RCA shields preferred).
Soldering iron
Desoldering pump
Power supply
2 ohm current limiting resistor (hollow cylindrical ceramic 100w preferred)
Please (and this applies to anyone who needs repair help) use your sig line to list all equipment you have, editing it as equipment changes. Include the model numbers. If you can't do this due to being a new member, make a list in the next post.
Top of page, menu USER CP >> EDIT SIGNATURE
Oscilloscope (yes or no)
Multimeter(s)
Type of signal source (grounded RCA shields preferred).
Soldering iron
Desoldering pump
Power supply
2 ohm current limiting resistor (hollow cylindrical ceramic 100w preferred)
Sorry Perry as I am learning.
So to backup a little bit the amp powers on and has clean sound but seems low that is why I was asking about what would the rail voltage be on this amp. I have a RF Power 300 which gives about 25v on the outputs, just to compare.
With nothing connected to the amp, what's the resistance between the RCA shields and the primary ground?
Perry resistance between the RCA shields and the primary ground is 121.03 ohms
At what point in the amp did you measure the rail voltage?
There are two 2N5639 transistors near the center of the board in the audio section. What is the DC voltage on leg 3 of those transistors?
There are two 2N5639 transistors near the center of the board in the audio section. What is the DC voltage on leg 3 of those transistors?
Perry see the attached picture and I circled 4 resistors that I don’t see the same on your amps.
5 band
Brown
Black
Orange
Gold
White
5 band
Brown
Black
Orange
Gold
White
At what point in the amp did you measure the rail voltage?
They are in the amp but are slightly different. Those resistors are 10k ohms. The ones in the amps I posted have a more conventional marking.
They are in the amp but are slightly different. Those resistors are 10k ohms. The ones in the amps I posted have a more conventional marking.
The outputs are bipolar transistors so they have no gate. They are base, collector, emitter. The base, in this circuit, is probably close enough but you should measure on the output leg of the rectifiers.
What's the DC voltage across the red and black wires of the amp when it's on?
Did you measure the voltage across the Zener diode when the amp was on?
It's odd that the amp had audio when the muting transistors had 0v on their gates. Re-check the voltage when the amp is on.
What's the DC voltage across the red and black wires of the amp when it's on?
Did you measure the voltage across the Zener diode when the amp was on?
It's odd that the amp had audio when the muting transistors had 0v on their gates. Re-check the voltage when the amp is on.
What's the DC voltage across the red and black wires of the amp when it's on?
Voltage between the red and black: 3.2695v
Did you measure the voltage across the Zener diode when the amp was on?
13.154v
Re-check the voltage when the amp is on?
0.0018v
Note: all 3 legs of the 2n5639 have the same voltage.
Voltage between the red and black: 3.2695v
Did you measure the voltage across the Zener diode when the amp was on?
13.154v
Re-check the voltage when the amp is on?
0.0018v
Note: all 3 legs of the 2n5639 have the same voltage.