Banned
Joined 2002
Banned
Joined 2002
OK...I hooked everything up for a quick bench test...no inputs...
On both boards, only one of the mosfets(Q6) have voltage? normal?
Also, even the ones that have voltage are not warm at all...mounted temporarily on a sheet of aluminum...
Can someone give some guidance as to what voltages ought to be at particular critical points? I could probably stumble through but I'm sure someone has been here before...
Thanks in advance...
On both boards, only one of the mosfets(Q6) have voltage? normal?
Also, even the ones that have voltage are not warm at all...mounted temporarily on a sheet of aluminum...
Can someone give some guidance as to what voltages ought to be at particular critical points? I could probably stumble through but I'm sure someone has been here before...
Thanks in advance...
Banned
Joined 2002
can you post pictures ?
Do you have all 3 power wires connected ? Positive negitive and gnd ?
jase
Yes...all power and earth ground connected from the wall to PSU board and to ch ground on the amp board.
Here are some voltage observations...
Q1: 9.2 -17.3 3.2
Q2: 0 -15.6 3.2
Q3: 13.2 3.2 16.35
Q4: -17.3 -17.3 -15.59
Q5: 17.1 17.2 17.2
Q6: -17.3 17.1 -15.6
Q7: 17.2 17.3 17.1
I hooked up an input and a small test speaker and there is no sound coming out...
I also took readings at all resistor terminals so I have those if it helps...
Carl
Here are some voltage observations...
Q1: 9.2 -17.3 3.2
Q2: 0 -15.6 3.2
Q3: 13.2 3.2 16.35
Q4: -17.3 -17.3 -15.59
Q5: 17.1 17.2 17.2
Q6: -17.3 17.1 -15.6
Q7: 17.2 17.3 17.1
I hooked up an input and a small test speaker and there is no sound coming out...
I also took readings at all resistor terminals so I have those if it helps...
Carl
Banned
Joined 2002
Banned
Joined 2002
I tried 2 more things last night...
1. finished adding the R to my PSU...3-0.47ohm resistors per rail (thought maybe the temporary jumper wasn't passing enough current???)
2. replaced the ZTX450's thinking maybe they got fried??? (unsure how to properly test though)
Still getting 17.4V per rail which is good...but why the @#$% is there no current passing through the source resistors and why is there no voltage across D1 and D2?????
Still getting about 17V at each leg of the source resistors to ground.
Once funny thing is that I am getting about 5V at D3...D5 is getting voltage...cant remember exactly but maybe it was 14 or so...
I even replaced the FET's with 2 spares I had not used just in case they blew the first time I fired it up.
This, I guess, is leading me to Q1,2,and 3...I do not know how to test them and by ruling almost everything else out leads me to believe that these may be the cause of my great frustration. Is there any simple DMM check I can perform on them for at least some type of rudimentary GO/NO GO without having to try and remove them??? I have a greenlee DM-20 that does have a diode setting.
1. finished adding the R to my PSU...3-0.47ohm resistors per rail (thought maybe the temporary jumper wasn't passing enough current???)
2. replaced the ZTX450's thinking maybe they got fried??? (unsure how to properly test though)
Still getting 17.4V per rail which is good...but why the @#$% is there no current passing through the source resistors and why is there no voltage across D1 and D2?????
Still getting about 17V at each leg of the source resistors to ground.
Once funny thing is that I am getting about 5V at D3...D5 is getting voltage...cant remember exactly but maybe it was 14 or so...
I even replaced the FET's with 2 spares I had not used just in case they blew the first time I fired it up.
This, I guess, is leading me to Q1,2,and 3...I do not know how to test them and by ruling almost everything else out leads me to believe that these may be the cause of my great frustration. Is there any simple DMM check I can perform on them for at least some type of rudimentary GO/NO GO without having to try and remove them??? I have a greenlee DM-20 that does have a diode setting.
Banned
Joined 2002
Take a break and come back, clear mind sometimes helps.
Use the attach schematic to measure the voltage acoss the IRF9610's and the ZTX. Notice that the component names are different from Brian's board, but when you look at both schematic together, you can tell which is which. Hopefully, this will help you to isolate the trouble area.
Use the attach schematic to measure the voltage acoss the IRF9610's and the ZTX. Notice that the component names are different from Brian's board, but when you look at both schematic together, you can tell which is which. Hopefully, this will help you to isolate the trouble area.
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