BRZ1700
Hifoncs no + rail voltage
Rebuilt power supply, get square wave on gate and center pin on the 3205 fets plus on the output of the transformers..
12V IN 1.7 Amp
Put the negative rectifiers in and get around -55 volts. both sides
Put the positive rectifiers in and get nothing plus the power supply meter goes to zero amps but does not shut down or blow fuse.
I don't no where to look causing this, am assuming it has a short on the amp side of the circuit.
Any ideas?
Hifoncs no + rail voltage
Rebuilt power supply, get square wave on gate and center pin on the 3205 fets plus on the output of the transformers..
12V IN 1.7 Amp
Put the negative rectifiers in and get around -55 volts. both sides
Put the positive rectifiers in and get nothing plus the power supply meter goes to zero amps but does not shut down or blow fuse.
I don't no where to look causing this, am assuming it has a short on the amp side of the circuit.
Any ideas?
Just 5 amp fuse, Did blow the fuse this time and no square wave now so guess I blew the tl594 again.
Think I am going to walk away from this amp, way to many hours in it.
I bought you repair guide and it helped a lot. you learn a lot from screwing up as well but still don`t understand enough for all the different trouble shooting needed.
Thanks Berry
Greg
Think I am going to walk away from this amp, way to many hours in it.
I bought you repair guide and it helped a lot. you learn a lot from screwing up as well but still don`t understand enough for all the different trouble shooting needed.
Thanks Berry
Greg
It's very difficult to damage the 594 IC.
Pull the rectifiers and see if it will power up without blowing the fuse.
You need to get some sort of limiter. Section 6 of the 'Equipment' page if you didn't see it.
Pull the rectifiers and see if it will power up without blowing the fuse.
You need to get some sort of limiter. Section 6 of the 'Equipment' page if you didn't see it.
Dech,
Try to get a voltage and current limiter power supply.
I currently have 2x 0-30v and 0-10a power supplies.
I know this could be a good investment, but this investment is so much worth it.
A good cheap alternative is to use a power supply from banggood (brand is long wei), costs only 50eu and will make this things much easier.
It is really important to have a current limiter as Perry stated. Otherwise you could kill more components then you would like to... (I killed more money in amps by not having a current limiter then the money I paid for my power supplies)
Is the output of the positive rectifier as good as 0v? Or is it close to around 1v of output.
If it is 0V steady, maybe your rectifier is dead.
If you have a little voltage on the rectifiers output you probably have a short circuit in your output section which pulls the rectifiers voltage down.
In my experience, this could be caused by some shorted capacitors in the output section, give it a beep with the multimeter 😀
Try to get a voltage and current limiter power supply.
I currently have 2x 0-30v and 0-10a power supplies.
I know this could be a good investment, but this investment is so much worth it.
A good cheap alternative is to use a power supply from banggood (brand is long wei), costs only 50eu and will make this things much easier.
It is really important to have a current limiter as Perry stated. Otherwise you could kill more components then you would like to... (I killed more money in amps by not having a current limiter then the money I paid for my power supplies)
Is the output of the positive rectifier as good as 0v? Or is it close to around 1v of output.
If it is 0V steady, maybe your rectifier is dead.
If you have a little voltage on the rectifiers output you probably have a short circuit in your output section which pulls the rectifiers voltage down.
In my experience, this could be caused by some shorted capacitors in the output section, give it a beep with the multimeter 😀
Well walked away till the next day.
I got it running again, all the right voltages and + and - rail.
At first was not getting anything but 12v on the 3205 fets
So start checking my remote voltage, I added a terminal strip for mounting the driver board earlier and basically found I had a broken ground on that terminal. Fixed that and got my rail - voltage back and good square wave back. I found a small short on the + rail on the output fets and fixed that and basically now had both rails.
Now put my output fets in and all was good . all voltages, no heat at all and only pulling couple amps.
Then, I don't know, everything was good and start putting amp back in case so I could mount to heat sink
I also did what Perry said and added 2ohm to power supply plus still had 7.5 amp fuse in .
Then noticed it was pulling lot more current, 10-12 amps at idle.
Basically have it out again and turn on get green light but all the power supply fets get hot quick, think one side and bit more then the other but both get hot. pin 4 and 6 have 12 volts and 5 ground on the 11 pin driver board terminal. Checked diodes and cant find any shorts. Q1 and Q2 seem ok on driver board, checked for shorts around fets, guess will pull rectifiers again but I nut sure from there.
I know i need better power supply
have 5-50v 3 amp and 13.8 10amp linear
I am using just a computer supply with fuse and 2 ohm now.
Was just about to go to car battery when this happened.
I got it running again, all the right voltages and + and - rail.
At first was not getting anything but 12v on the 3205 fets
So start checking my remote voltage, I added a terminal strip for mounting the driver board earlier and basically found I had a broken ground on that terminal. Fixed that and got my rail - voltage back and good square wave back. I found a small short on the + rail on the output fets and fixed that and basically now had both rails.
Now put my output fets in and all was good . all voltages, no heat at all and only pulling couple amps.
Then, I don't know, everything was good and start putting amp back in case so I could mount to heat sink
I also did what Perry said and added 2ohm to power supply plus still had 7.5 amp fuse in .
Then noticed it was pulling lot more current, 10-12 amps at idle.
Basically have it out again and turn on get green light but all the power supply fets get hot quick, think one side and bit more then the other but both get hot. pin 4 and 6 have 12 volts and 5 ground on the 11 pin driver board terminal. Checked diodes and cant find any shorts. Q1 and Q2 seem ok on driver board, checked for shorts around fets, guess will pull rectifiers again but I nut sure from there.
I know i need better power supply
have 5-50v 3 amp and 13.8 10amp linear
I am using just a computer supply with fuse and 2 ohm now.
Was just about to go to car battery when this happened.
With the limiter in the circuit, do the drive signals for the PS FETs look OK?
Did you re-check the output transistors to confirm that none had failed?
Did you re-check the output transistors to confirm that none had failed?
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WOW you nailed it.
Output fets are blown, I keep missing the obvious.
I wonder what I did wrong to blow them/
Thanks again Perry
Output fets are blown, I keep missing the obvious.
I wonder what I did wrong to blow them/
Thanks again Perry
They can overheat quickly and fail if not clamped tightly to the heatsink, especially if the drive signals aren't quite right.
fets are ok, the short was on the pins on one of the output fets.
I thought I checked these things many times but a short is a short.
I thought I checked these things many times but a short is a short.
If you';re not using a toothbrush and acetone to completely clean all solder joints, you need to do so. It makes it much easier to see something like a solder bridge or a stray flake of solder... even dirty flux can be slightly conductive.
I do Perry, this output fet where the short cleared after removing is the one that had board damage and I cut out what I thought was all the burnt board. I think the board was conductive under higher amp load. I am not sure though, I may have just missed the short installing the fets.
But now back to power supply
But now back to power supply
1 5.63v
2 2.55v
3 4.67v
4 3.96v
5 1.52v
6 3.68v
ground
8 11.92v
9 .o mv
10 .2mv
11 11.94v
12 11.94v
13 5v
14 5v
15 5v
16 .1mv
tl594 chip
2 2.55v
3 4.67v
4 3.96v
5 1.52v
6 3.68v
ground
8 11.92v
9 .o mv
10 .2mv
11 11.94v
12 11.94v
13 5v
14 5v
15 5v
16 .1mv
tl594 chip
oh and the red pertect led is on so guess i have to find fault causing pin 9 and 10 to have no voltage.
Its hard working on this cause its my first switching power supply and and fets plus never worked with smd parts before.
Old school tube gear and or stereos.
But making a lot of mistakes helps the learning process.
Its hard working on this cause its my first switching power supply and and fets plus never worked with smd parts before.
Old school tube gear and or stereos.
But making a lot of mistakes helps the learning process.
Post a good quality photo of the component side of the entire main board and the component side of any driver boards.
Pin 1 of the 494 is being driven high and that's shutting the amp down. The photos will help me know what this amp is.
Pin 1 of the 494 is being driven high and that's shutting the amp down. The photos will help me know what this amp is.
q214 was the output fet where the short was
nothing looks bad on the driver board that i can tell
nothing looks bad on the driver board that i can tell
