Salas SSLV1.3 UltraBiB shunt regulator

Right it looks as in diode test M1 has drop both ways from drain to source of 0.025v . The type i have from kit is FQP3P20. What are current in stock parts for this ultra bib 1.3 for all q and J as well as M1 and M2 ? Would like to make stock just incase.
Read post #1 footnotes. As for M1... IRF9610 can replace FQP3P20 if no more than 1A CCS is set.
 
Ok. So I installed new M1 from second kit bag . Installed 22ohm ( nearest value i jad ) dummy resistor . Decrease trimmer to 0 ohm . Now I have 11.44v DC output . No led lit.
R1 = 1ohm , voltage across it 470mv.
Voltage across R8=340mv.
Nothing across R5,6,4,7
Voltage on M1 between GS 0.59V
Voltage on M2 between GS 3.29.
I have built L-adapter on friday and it worked straight no issues. Where is the problem here ?
Pulled all Q and J look ok . Is 75k plus 10k trimmer too much of a resistance to drop voltage . And why led's aren't working ?. I am making order from mouser looks as j113 is the only option .
I mean its a realitively simple build . Anything else i should add to order ?
 
Normally no problems when CCS to load ratio is proper, Ubib has been made and applied more than a lot of times by diyers. Static can kill Mosfets before or during assembly/rework is an odd problem or some small semi can die during soldering. Check if you have a broken LED issue too. The 3mm ones are sensitive to soldering power sometimes. When M1 properly conducts in this circuit should also show few Volt VGS.
 
Ok. Shame to say. I installed red led wrong way . Pulled them out , reinstalled properly . Installed 0.68 ohm back . Fit 10 ohm 5w . Power up ,adjust 7.5v all looks good . Lesson learned . Just one mosfet down . Thank you for your help Mr Salas. Just to be safe i leave it for a while 10w resistor reached 137 degress celcius after 10 min . Heatsink steady on M1 - 60 degrees. I will sink resistor and let it run overnight i think .
Sooooooo happy .
Will report after listening expect huge improvement over wall plug supply .
 
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Hi Salas.

I posted about GLED431 reference mod few days ago.

Now i put back the standard R5 and R6 resistors (270R) and replaced generic red leds with HLMP-6000 leds. This is the best combination by far.
It seems that R5 and R6 values should be as they are. So standard reference is perfect!
 
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Things may not be as stable as I was hoping, it did drop down about 0.5vdc after an hour, I readjusted and seems to be holding again. I'll go ahead cold start and leaving the psu on for half a day and checking in multiple times, repeat that across some days, see how things behave. Ambient temp is 20C.
 
Maybe different orientation of the bead and/or different cut lead length could help? Like how close or not is to the same temperature Δ affected area as the circuit's elements... It could even takes to try a few NTC of nearby specs to really nail it. Or different absolute value ones within a batch. But OK, if its surely better than without the specific NTC type's compensation those are very good news already.