just ran it in idle with bias pot set as low as they go on the channel that heats up the voltage at start up was .005 ran it for a while and and about 3 minuets it had jumped up to .020
i just ran a test to see how much current it draws on idle. it was drawing about 1.6a it was getting a jumpy reading to from about 1.6 - 1.9a is this normal?
Did it go to 0.020v on both channels?
Did you replace the outputs in both channels?
With 'no audio signal', the idle current should have been constant. You could have a dirty bias pot. If you connect your meter across the emitter resistors for each channel, does the voltage across the emitter resistors remain constant on both channels when the idle current is fluctuating?
If not, does it change for one channel, or both channels?
If one channel, which channel?
Did you replace the outputs in both channels?
With 'no audio signal', the idle current should have been constant. You could have a dirty bias pot. If you connect your meter across the emitter resistors for each channel, does the voltage across the emitter resistors remain constant on both channels when the idle current is fluctuating?
If not, does it change for one channel, or both channels?
If one channel, which channel?
It only went to .020v in the channel with the new transistors
with the bias pots set to there lowest the channel with the old transistors fluctuates between .001v and .003v the channel with the new transistors fluctuates between .004v and .005v
and i noticed that one of the surface mounted resistors on the back side of the board looks a bit bit dodgy it has 330 printed on it dose this mean its 33 ohm?
would the burnt resistor be allowing more current to flow to the channel that's running hot?
with the bias pots set to there lowest the channel with the old transistors fluctuates between .001v and .003v the channel with the new transistors fluctuates between .004v and .005v
and i noticed that one of the surface mounted resistors on the back side of the board looks a bit bit dodgy it has 330 printed on it dose this mean its 33 ohm?
would the burnt resistor be allowing more current to flow to the channel that's running hot?
You can measure the 33 ohm in the board to determine if it's out of tolerance.
I don't have the schematic for that amp so I don't know the function of that resistor.
When the voltage across the emitter resistor went to 0.020v, how much current was the amp drawing from the power supply.
I don't have the schematic for that amp so I don't know the function of that resistor.
When the voltage across the emitter resistor went to 0.020v, how much current was the amp drawing from the power supply.
found out that it was my finger touching the legs on the transistors causing the voltage to spike
I'm going to order the resistor. Should i also get an new set of pots?
I'm going to order the resistor. Should i also get an new set of pots?
The squeeking is probably coming from the transformer resonating at the switching frequency in the SMPS section of the amplifier.
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