I have changed circuit breaker.
Strange noise have gone but still no sound from left channel. Also 4.2v between gate- source pins.
I have no time to add led tonight so may be tomorrow.
Also I drilled holes for PCB slightly wrong place.
When I screw PCB, it wound then there is small crack.
If nothing happen when add led, I use another PacB
Left channel R2/1.26V R1/30mV
Q2/4.22V Q1/37mV
Right channel R2/0.78V R1/10mV
Q2/4.16V
Right channel Q1 Gate-Source voltage is something wrong.
On and off so cannot check voltage.
The sound coming from left side so its wired.
I bought 2sk170/2sj74 from pankydawgs,ebay.
I didnt check because didnt know how. Checked only direction to solder.
Also I noticed diode is getting very hot.
I am using 10A sic-sbd.
On my Ucd180 amp, I use same one without heat sink but they never get hot.
Q2/4.22V Q1/37mV
Right channel R2/0.78V R1/10mV
Q2/4.16V
Right channel Q1 Gate-Source voltage is something wrong.
On and off so cannot check voltage.
The sound coming from left side so its wired.
I bought 2sk170/2sj74 from pankydawgs,ebay.
I didnt check because didnt know how. Checked only direction to solder.
Also I noticed diode is getting very hot.
I am using 10A sic-sbd.
On my Ucd180 amp, I use same one without heat sink but they never get hot.
V R1 and V R2 should be near the same values Eg between 0.47V to 0.75V
Vgs M1 and Vgs M2 should be near the same values Both should be between 4V and 5.5V
Your values are no where near correct. Either you haven’t adjusted trimpots correctly, or you have some serious issues that need fixing.
The Jfets will not affect these values so I wouldn’t worry about that till you have the output stage working correctly.
Vgs M1 and Vgs M2 should be near the same values Both should be between 4V and 5.5V
Your values are no where near correct. Either you haven’t adjusted trimpots correctly, or you have some serious issues that need fixing.
The Jfets will not affect these values so I wouldn’t worry about that till you have the output stage working correctly.
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Just because you turn one trimpot clockwise doesn't mean the other trimpot needs to be turned clockwise (or vice versa). It will depend on how they were installed.
On my F6, they need to be turned in opposite directions to correctly set up the amp.
If the voltages at the powersupply are correct, then reset trimpots back to the middle and start again.
First determine which way each trimpot needs to be turned to turn on each mosfet.
Constantly measure these values as well as dc offset.
On my F6, they need to be turned in opposite directions to correctly set up the amp.
If the voltages at the powersupply are correct, then reset trimpots back to the middle and start again.
First determine which way each trimpot needs to be turned to turn on each mosfet.
Constantly measure these values as well as dc offset.