You can use it as is and hotrod later to compare. 55mA are 6 times the audio part's demand. Its just the MOSFETs are not triggered to much transconductance yet.
Took another measurement. V over R1 is 1.81 and slowly sinking whilst it's warming up.
34R gives abt 53mA. Should I add another 68R in parallel?
34R gives abt 53mA. Should I add another 68R in parallel?
That gives no margin for nodes interconnection errors, only wrong orientation or a bad semi could give problems. Easily traceable.
Broken semi bcs it worked at first. I managed to listen to a whole LP before I decided to do some measurements 🙁. Then it started to rise on the positive rail. 12.5V at first and rising - now it is outputting 16.9V. It doesn't regulate on the second IRFP9240... Thats what I found out so far.
No, I haven't fixed it. Took a look and 10V in black is your annotation, I have over 16V (the red text). I'm still waiting for New IRFP9240... But that might not be the problem.
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Sorry, I am not at site anymore. I have to check that tomorrow.
Thanks for your help so far.
Regards
Thanks for your help so far.
Regards
Had the ohmic measurements with me of site:
All 3 2sk170 has between 34.6R to 37R. So no shorts but of course one might have turned into a resistor 🙂.
Q1 shows unlimited resistance and measuring feels like measuring over an electrolyt, infact C2 in series with R1.
Q2 shows abt 516R.
Regards
I tried to up the current in mine but heard no discernible difference. Eventually I opted for cool running and reliability with about 180mA.
I increased the current in mine and did hear a difference... Only you can tell if it works for you, try it and see.
It struck me that the Q2 I referred to is actually Q4 in your schema in page 120 which I am referring to. The second line IRFP9240...
http://www.diyaudio.com/forums/pass-labs/176723-mezmerize-dcb1-building-thread-120.html#post3814110
Do you still want me to get it out and check idss?
Regards
It does not have Idss because its enhancement mode MOSFET not DMOS but its suspicious. If you don't have a specialized component tester try something like this: MOSFET testing To check P-channel FETs, you will need to reverse the meter leads.