Hi,anyone here know the actual working rail voltage of the MM4000.1D?Cap rated at 120V itself.Got a on-hand unit with blown transient voltage suppressor,PK6E250A,on one rail.
Also duty cycle on the DC-DC PWM (TL494 based) is around 33%,is that normal?
Also duty cycle on the DC-DC PWM (TL494 based) is around 33%,is that normal?
Most of the 3S-tech type amps are unregulated so they run at 50% duty cycle.
Does the rail voltage or the pulse width vary when you adjust the 12v supply input voltage?
Does the rail voltage or the pulse width vary when you adjust the 12v supply input voltage?
I also had a similar problem.
Most of the time, due to lack of replacement, I simply eliminated the transient suppressor and the amplifier works perfectly even without that diode.
Could someone explain to me what these suppressor diodes are for?
this is the board...
2 IRS21844S and only TL072 and LM211.
LM293 is on the main board.
Attachments
I don't have a variable power supply but the supply voltage is rated at 12.4V.
Also,got 2 output fets were blown.....so i assume i should remove all remaining fets for further testing,on the rail voltage and also the gate voltage?
If you have a current limiter like an automotive headlamp or 2 ohm dummy load resistor, insert it in the B+ line. That will reduce the input the voltage.