I noticed that the negative power supply heats up less, the positive power supply heats up more... it heats up very much... I'm afraid it will burn out... What does heating affect?
How can you further reduce the heating of radiators?
What can be done?
How can you further reduce the heating of radiators?
What can be done?
Lessen CCS setting with higher value R1 if one supply sees less load. What it does not burn in load it burns on itself. That's what a shunt regulator does.
Black on base . BE Q2 = 794 , Q3 = 792 , Q1 = 767. From online description of correct measurement it looks as if the are measuring as good. Shows drop in both directions .
Pulled J1 and test with 2 multimeters . Seems ok both black probes on gate , red on source and gate = no continuity. Opposite drop 0.760 . Sigh . Pulling components out is a mision . But iam dedicated would love to give it a listen today .
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.
Jfets can be measured with Ohmmeter for RDS. With one probe on gate and source pins at the same time. The other probe on drain pin.Pulled J1 and test with 2 multimeters . Seems ok both black probes on gate , red on source and gate = no continuity. Opposite drop 0.760 .
Read post #1 footnotes. As for M1... IRF9610 can replace FQP3P20 if no more than 1A CCS is set.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.
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 ?
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 .
Sooooooo happy .
Will report after listening expect huge improvement over wall plug supply .
No worries, we do worse all the time. Congratulations for debugging it. It was some sort of Led issue after all.
You run 5.625W constantly on that dummy load resistorThank 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 .

Always nice to know impressions in system applications. About your L-Adapter build too.Will report after listening expect huge improvement over wall plug supply .
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!
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!
Hi all!
I want to ask, has anyone already adapted the regulator to digital? Unfortunately, I don’t have an oscilloscope to measure and understand. What changes need to be made for the digital part?
I want to ask, has anyone already adapted the regulator to digital? Unfortunately, I don’t have an oscilloscope to measure and understand. What changes need to be made for the digital part?
This one is fancy, you can point it around. NTCM-4K7-B3470 pearl NTC
I picked some of these up. It's only been on for about 30 minutes or so, but after dialing in the temperature it has not budged at all. 👍
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.
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