Nash hi
Nice to know you repaired it on first guess. About acetone I don't know because I have only used isopropyl alcohol and Cramolin Flux Off on this. I suggest you try a little acetone at the board's underside corner first as a test.
hi everybody,
i am really DIY beginner and just finished my first neg. and pos. ultrabib. so far so good.
connected it to a 12v r-core, leds are shining. but: output is about 16v, so i think something is wrong. trimmer on vr1 makes no difference, when i try to regulate.
i am going to resolder (soldered only on the back of the board, and will solder on the other side, too)
i would be glad, if i can be pointed into the right direction, on where i could start with my troubleshooting.
thanks again!
i am really DIY beginner and just finished my first neg. and pos. ultrabib. so far so good.
connected it to a 12v r-core, leds are shining. but: output is about 16v, so i think something is wrong. trimmer on vr1 makes no difference, when i try to regulate.
i am going to resolder (soldered only on the back of the board, and will solder on the other side, too)
i would be glad, if i can be pointed into the right direction, on where i could start with my troubleshooting.
thanks again!
Hi
Output looks like it's just the top input potential. First thing is it takes many turns on the 20k trimmer to make sure it went low enough.
Next thing is visual confirmation that the right components are in the right places with correct orientations in the right polarity regs (NMOS PMOS NPN PNP) then Vbe voltage checking of Q2 Q3 and Vgs voltage checking for M1 M2.
Output looks like it's just the top input potential. First thing is it takes many turns on the 20k trimmer to make sure it went low enough.
Next thing is visual confirmation that the right components are in the right places with correct orientations in the right polarity regs (NMOS PMOS NPN PNP) then Vbe voltage checking of Q2 Q3 and Vgs voltage checking for M1 M2.
hi salas,
false alarm, everything is fine. i had to turn the trimmer really often. (and i soldered the other two platines) so looking forward making first listening tests.
can perhaps somebody confirm r1 resistors for soekris dam dac1021 for me:
for the pos bib i soldered two 4.3 ohm 5w one on top, one at bottom of the board -> TUW3J4R3E Ohmite | Mouser Osterreich
and for the negative: one 3.9 ohm 2watt -> CPF23R9000FKB14 Vishay / Dale | Mouser Osterreich
i also have in stock these other versions, if better, please tell me:
CPF22R0000FKRE5 Vishay / Dale | Mouser Osterreich (2 watt 2 ohms) and
RS02B3R900FE70 Vishay / Dale | Mouser Osterreich (3 watt 3.9 ohm)
thanks everybody!
false alarm, everything is fine. i had to turn the trimmer really often. (and i soldered the other two platines) so looking forward making first listening tests.
can perhaps somebody confirm r1 resistors for soekris dam dac1021 for me:
for the pos bib i soldered two 4.3 ohm 5w one on top, one at bottom of the board -> TUW3J4R3E Ohmite | Mouser Osterreich
and for the negative: one 3.9 ohm 2watt -> CPF23R9000FKB14 Vishay / Dale | Mouser Osterreich
i also have in stock these other versions, if better, please tell me:
CPF22R0000FKRE5 Vishay / Dale | Mouser Osterreich (2 watt 2 ohms) and
RS02B3R900FE70 Vishay / Dale | Mouser Osterreich (3 watt 3.9 ohm)
thanks everybody!
Hello. I need help. This may have already been discussed, but I can't find any information yet. Assembled a mock-up of the Ubib positive regulator. The output voltage is adjustable from 5V to 7.25. R1 2R2. The voltage drop at R1 is 0.56. The diodes are glowing. Vds M1 -16.2V. Voltage drop at R7-1.67 V, R8-1.44 V, R4-1.9 V. Vbe of Bipolar transistors from 0.56 to 0.64 V. I suspect that the problem is somewhere in the area of J1, Q1.What else do you need to measure? Thanks.
Vds J1-13.6V!!!,J2-1.53V, J3- 0.75V The radiator is warm. Vgs M1-5.43V, M2-3.82V. Vgs J1-1.88V, J2-1.66V, J3-1.43V
Vds J1-13.6V!!!,J2-1.53V, J3- 0.75V The radiator is warm. Vgs M1-5.43V, M2-3.82V. Vgs J1-1.88V, J2-1.66V, J3-1.43V
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Hello. Assembled the regulator. It worked the first time you turned it on. The voltage is adjustable. When connecting a load of 100 R. the voltage drops. It becomes unstable and almost not regulated by VR1. I don't think it should be like this. R1-2.2 positive, 3.9 negative. R9-470R. C1 3300uF (temporarily) measured the voltage drop on the Jfet.
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I decided to measure the AC ripple with an oscilloscope. Against the background of its own noise, there are practically no AC voltage emissions. Am I doing the right thing? Or please tell me how to do it. The output voltage is 17 V. Load 100 R.
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