PING: George Herold
 

Greetings George,
I sent you an email but it bounced back. So I'm posting it here.
On Wed, 19 Mar 2014 19:26:02 +0000, you wrote:
Greetings George,
I too have had trouble posting to news groups through google. Anyway,
I don't know if power continues to the board when the machine is
turned off. All power is removed when off but what if there are caps
on other boards keeping something on the suspect board running? I can
touch the board when running and have done so. Nothing feels warm. Not
the caps or the ICs. I have tried the freeze spray with no luck. But I
did not spray the caps. Can I test the caps without risking damage to
the ICs on the board? I have a DVOM with a cap testing function.
Eric

Hi Eric, I was trying to respond to your question on sci.electronics.repair.. but google is broken and won't let me.

Hence this email

So when you turn off the mill to let it cool down does the PCB remain under power? If so then it may be that removing the power from the board is what causes it to
"fix itself".

The dipped caps are most likely tantalum and those can have problems. Can you get in and touch the board while it's failed?
You might find one of the caps is hot. I've seen them fail, but not completely blow up. If you can't touch them maybe you can hit it with some freeze spray.

Good luck,
Trouble shooting can be a pain sometimes...

George



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PING: George Herold
 

On Wednesday, March 19, 2014 6:47:41 PM UTC-4, wrote:
Greetings George,

I sent you an email but it bounced back. So I'm posting it here.

On Wed, 19 Mar 2014 19:26:02 +0000, you wrote:

Greetings George,

I too have had trouble posting to news groups through google. Anyway,

I don't know if power continues to the board when the machine is

turned off. All power is removed when off but what if there are caps

on other boards keeping something on the suspect board running? I can

touch the board when running and have done so. Nothing feels warm. Not

the caps or the ICs. I have tried the freeze spray with no luck. But I

did not spray the caps. Can I test the caps without risking damage to

the ICs on the board? I have a DVOM with a cap testing function.

Eric


Hi Eric.. It's weird that my email bounced.

As someone said in antoher thread it would be a good idea to check the power supplies too. (When it's failed.)

George H.