Re: Dead PET 2001

Re: Dead PET 2001

From: Philip Lord <random6000_at_mac.com>
Date: Tue, 11 Aug 2009 21:31:20 +0900
Message-id: <4844D789-BBDE-4CA8-843C-3671B8D1B0BC@mac.com>
Update:
With the red leads detached from the capacitor I tested the voltages  
again this evening.
Where as before I was getting over 8VDC, now I'm only getting 0.5VDC  
on the cathode side of the diodes...very strange. I wish I knew what  
was going on.
Maybe it's time to start by removing the diodes and testing them.

Phil


On Aug 10, 2009, at 3:14 PM, Philip Lord wrote:

> Thanks William,
> I did as you described.
> I removed the red wires from the capacitor and re-measured the  
> voltages on either side of the two diodes.
> As before I get just over 8VAC on the anode side, but now I get   
> just over 8VDC on the cathode side.
>
> I also tested the large capacitor using the ohm meter on my digital  
> multimeter. It starts at Zero ohms and slowly rises.
>
> I apologies for my lack of electronic knowledge, and once again ask  
> what I should try next? Hopefully we are narrowing down the problem.
>
> Cheers again
> Phil
>
>
>
> On Aug 10, 2009, at 1:07 PM, William Levak wrote:
>
>> On Sun, 9 Aug 2009, Philip Lord wrote:
>>
>>> oops...Please excuse my bad typing...what I mean to say was:
>>>
>>> Yes, I admit I was checking the voltage on the inside of the  
>>> diodes with my multimeter (digital) set to AC. I just rechecked  
>>> with it set to DC and the reading is still in the millivolt range.
>>> If the diodes are indeed the culprit, I find it strange that both  
>>> diodes would be open?
>>> As for the J8 connecter, it basically looks new, no dirt, or  
>>> burning at all.
>>
>> You said the fuse blew several times.  That would be enough to blow  
>> the diodes.  Disconnect the red wires from the capacitor, and check  
>> the voltages again.  Also check the capacitor for shorts.  If you  
>> don't have a capacitor tester, you can use an ohm meter.  The  
>> resistance should start at zero and build up.
>>
>>     Message was sent through the cbm-hackers mailing list
>
>
>      Message was sent through the cbm-hackers mailing list


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Received on 2009-08-11 14:52:54

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