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Old 26th February 2010, 05:41 PM   #911
Salas is online now Salas  Greece
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Problem. Exchange Q15 first, and then Q14 if no cigar. Also watch their orientation. I hope it will not have to be Q16.
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Old 26th February 2010, 06:08 PM   #912
adamus is offline adamus  United Kingdom
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15 and 14 replaced... no cigar.

Must be the mosfet. bugger!
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Old 26th February 2010, 07:16 PM   #913
Ryssen is offline Ryssen  Sweden
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Quote:
Originally Posted by quanghao View Post
Yes the Salas shunt I still have some PCB!
Ok,money sent for 2 pcbs.
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Regards ke
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Old 26th February 2010, 08:19 PM   #914
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replaced q16 and still the same.... hmmmm
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Old 26th February 2010, 09:06 PM   #915
Salas is online now Salas  Greece
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Look on its correctly functioning (?) twin +5V for parts orientation, correct types and values on parts, connections and copper lines underneath, measurements. There must be a bug somewhere in your build. Vgs (gate to +V) of the Mosfet must be around 4V and drop across Q14 must be existing. Is R15 actually 47R?
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Old 26th February 2010, 09:11 PM   #916
leflu is offline leflu  Germany
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Hi Salas,
if i understand you right...you recommend to skip the tl431
Regulator and only regulate from salas-reg pointed at 5V
and -5V. Right?
Would you suggest matching of LEDs? To what current should
they be matched each?

Greetings Ulf
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Old 26th February 2010, 09:16 PM   #917
Salas is online now Salas  Greece
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Its not my design, I don't recommend. I just thought aloud. This must come officially from the maker and GB holder, or any other successful tweaks from the builders. As for the part that they adopted, namely the 5V SSV1.0 reg array, no you don't need to match leds, since you got trimmers.

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Old 26th February 2010, 09:57 PM   #918
adamus is offline adamus  United Kingdom
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the gate of q16 is sat at the output voltage. so surely it points the finger at q14.... trouble is i have already replaced it.

I'll try replacing again.

edit, replaced and no joy. I'll try q15 again..... this has me stumped.

Last edited by adamus; 26th February 2010 at 10:16 PM.
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Old 26th February 2010, 10:17 PM   #919
Salas is online now Salas  Greece
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I repeat, is R15 correct value?
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Old 26th February 2010, 10:19 PM   #920
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yep, 47ohms.the 47ohm bc550 junction measures 338mv.

Last edited by adamus; 26th February 2010 at 10:25 PM.
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