Im using 220 ohm resistors since the guy from audio clinic says thats what i need in the amp. He said if i drop them down to 100 ohms ill throw the dead time off in the amp and get cross conduction. Is that true?
In this circuit, reducing the value of the resistor will increase deadtime. The only way you could safely use 220 ohm resistors is if there is deadtime set by a voltage divider on pin 4 of the 494 or if there were a diode in parallel with the gate resistors.
If this amp has a regulated power supply, clamp everything down and power it up at ~14v DC. Then lower the DC voltage to ~11v. If the idle current increases when you lower the voltage, the drive circuit will have to be modified.
Were you able to get a schematic diagram for the amp?
If this amp has a regulated power supply, clamp everything down and power it up at ~14v DC. Then lower the DC voltage to ~11v. If the idle current increases when you lower the voltage, the drive circuit will have to be modified.
Were you able to get a schematic diagram for the amp?
The AL version has a lower threshold voltage which would make it even more difficult to drive (with common drive circuits used in car amps).
Never got a diagram for this amp.
Here are some pics of the power supply let me know if you need better ones just wanna get this amp up and running
Here are some pics of the power supply let me know if you need better ones just wanna get this amp up and running
There's likely deadtime programmed into the drive signal by a voltage divider on pin 4. The 220 ohm resistor 'may' work but you REALLY need to check it by lowering the DC voltage to force the 494 to full duty cycle (if it's a regulated power supply).
How many fets do i need in each bank to test it?? and also do i put the z44's in or just the buz 102's since most of the buz102's are shorted
You'll need to have all of the FETs (Z44s or whatever you intend to use as substitutes) in the circuit.
Ok replaced the power supply fets with IRFZ44n's Orginals were BUZ102's.
I also replaced all the rectifiers in the amp FES16JT's. Checked the gate resistors and the drivers all seem to test fine.
Amp draws excessive current . So i pulled the rectifiers but with them being out of circuit the amp wont power on or even attempt to.
So I checked the outputs and all seem fine. So im going to put the rectifiers back in the amp.
Wondering what i need to check since it draws excessive current?
The reason im asking is because with the old power supply fets in the amp it still powerd on just went into protection mode since a few of them were shorted and didnt draw excessive current
I also replaced all the rectifiers in the amp FES16JT's. Checked the gate resistors and the drivers all seem to test fine.
Amp draws excessive current . So i pulled the rectifiers but with them being out of circuit the amp wont power on or even attempt to.
So I checked the outputs and all seem fine. So im going to put the rectifiers back in the amp.
Wondering what i need to check since it draws excessive current?
The reason im asking is because with the old power supply fets in the amp it still powerd on just went into protection mode since a few of them were shorted and didnt draw excessive current
Clamp all semiconductors and power it up through a current limiting resistor. Measure the DC voltage across each of the emitter/source resistors to determine which channel is causing the excessive current draw.
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