Hoi John,
You just need to take the soldering pads from the diodes that are connected to the + and - of the big capacitor, checking the pcb layout or using a dmm meter will tell you which are the right ones. I soldered some pcb connecters to the saligny rectifier and connected these with the wires.
Good luck!
You just need to take the soldering pads from the diodes that are connected to the + and - of the big capacitor, checking the pcb layout or using a dmm meter will tell you which are the right ones. I soldered some pcb connecters to the saligny rectifier and connected these with the wires.
Good luck!
Attachments
Hello!
Assembled UltraBib Pos board (my own develop). Configuration:
* transformer 9V
* Rf 2.8Ohm (215mA)
* C1 10000uF
* M1 FQP3P20
* power through safety lamp (60W).
Results: dims are off, output voltage low. Read this post Salas SSLV1.3 UltraBiB shunt regulator
Voltages:
R1 - 0.8V
R5 - start from 0.380V and goes down
R7 - 0V
Rectifier works well.
What could be wrong? May be wait 10-20 seconds for turning on UltraBib.
Assembled UltraBib Pos board (my own develop). Configuration:
* transformer 9V
* Rf 2.8Ohm (215mA)
* C1 10000uF
* M1 FQP3P20
* power through safety lamp (60W).
Results: dims are off, output voltage low. Read this post Salas SSLV1.3 UltraBiB shunt regulator
Voltages:
R1 - 0.8V
R5 - start from 0.380V and goes down
R7 - 0V
Rectifier works well.
What could be wrong? May be wait 10-20 seconds for turning on UltraBib.
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Hi
With Rf 2.8 Ohm you mean R1 I believe? Rf should be small like 0.33 Ohm, just forms an anti EMI RC filter with C1.
Some bug of wrong connection in your own development board? Some oscillation due to layout? A bad Q2? 0.8V across R1 pins is Q1 Vbe and it should have been around 0.6V. A bad M1 and/or Q1? If without safety bulb maybe a bad over current would have happened.
There is substantial inrush current at turn on, C1 charges up first, maybe a big value Rf and/or the safety bulb slow the start up too much?
With Rf 2.8 Ohm you mean R1 I believe? Rf should be small like 0.33 Ohm, just forms an anti EMI RC filter with C1.
Some bug of wrong connection in your own development board? Some oscillation due to layout? A bad Q2? 0.8V across R1 pins is Q1 Vbe and it should have been around 0.6V. A bad M1 and/or Q1? If without safety bulb maybe a bad over current would have happened.
There is substantial inrush current at turn on, C1 charges up first, maybe a big value Rf and/or the safety bulb slow the start up too much?
First check all Vbe and all Vgs in bipolar transistors and Mosfets as already placed when the circuit is energized. Around 0.5-0.7V for Vbe and 4-6V for Vgs are healthy in this circuit with these parts. Also check voltage drops across the Jfets source pin 270 Ohm resistors. The drops should be indicating 1-3mA current bias running through them.
In case of badly out of range described voltage indications replace the associated semiconductors. Also check bolts and pads for Mosfets good insulation.
In case of badly out of range described voltage indications replace the associated semiconductors. Also check bolts and pads for Mosfets good insulation.
Thank you Salas for advise.
My shame: download wrong pics of schema PF5102 so mixed on board G and D. Luckely all JFET alive, Ultrabib works with 9V trans:
Micro UltraBib 35x80 mm.
Some variant of replacement PF5102
2N5457 = PF5102, 1,25 €
My shame: download wrong pics of schema PF5102 so mixed on board G and D. Luckely all JFET alive, Ultrabib works with 9V trans:
Micro UltraBib 35x80 mm.
Some variant of replacement PF5102
2N5457 = PF5102, 1,25 €
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I rotate between three amps at present, all DIYers: the main amp is a variation of Dario's My_Ref Evo A LM3886 based amp, DrMordor's all-in-one tpa3255 class D amp, and a novel 7293—based amp from Audiokiller (Igor from Russia). Speakers are older Genesis Physics 210's. Not high end stuff but good enough for my ears.
Cheers, Pete
Thanks Salas! I find them to be wonderful (old fashion) floor standing speakers that reproduce music superbly. The tweeters are just so smooth. And, since I got them for free (from an old work colleague) it makes them that much better ;>)
Someday maybe Harbeths if my wife lets me…LOL
Pete
Someday maybe Harbeths if my wife lets me…LOL
Pete