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karvid  
#1 Posted : Saturday, March 27, 2010 12:04:49 PM(UTC)
karvid

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Hello,
I got a minor problem when I tried to adjust my Placid.

I followed the manula and adjusted the output voltage to 5,5VDC without problem.
BUT when I try to adjust the voltage across R17 to 0,35VDC I can only get 0,347 VDC using the pot.

My R_Core trafo gives sec secondary 9V/1A. When measured at Placid it measure 14,3VDC after the diode rectification.

Any idea on what to do or should I just leave like this?
NOTE: It was measured without load!



Russ White  
#2 Posted : Saturday, March 27, 2010 1:45:15 PM(UTC)
Russ White

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You should be just fine with 347ma. :) Just leave it as is.
karvid  
#3 Posted : Saturday, March 27, 2010 3:39:33 PM(UTC)
karvid

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Russ White wrote:
You should be just fine with 347ma. :) Just leave it as is.


Thanks! I will leave it as it is.
I noticed that when the PSU gets warm the voltage raises to more than 0,35 V.

Best regards
Kenneth
pedrop  
#4 Posted : Saturday, March 27, 2010 10:44:33 PM(UTC)
pedrop

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Russ,

I have the same issue as karvid. I had no problem adjusting VR4 to get 5.5VDC output. But, I couldn't adjust the voltage across R17 to get 0.35Vdc.
The maximum I get is 0.30Vdc after 30 minute warm up.

Note: Transformer primaries and secondaries are both wired in parallel. Secondary output is 10.6 Vac. All measurements under no load.

Any suggestion as how to get 0.35V across R17? Thanks.

Pedro
Russ White  
#5 Posted : Sunday, March 28, 2010 6:12:25 AM(UTC)
Russ White

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You can reduce R6. Even to the point of shorting it should be OK. I would try something like 4.7R if you have it. This controls the current going across VR4. So I would adjust the pot for a lower current before you power up for the first time after making that change. This is the trouble with JFETs. :) IDSS is inconsistent. :)

Cheers!
Russ

Edited by user Sunday, March 28, 2010 6:13:13 AM(UTC)  | Reason: Not specified

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