Emax

ON FUrther thought, did you try disconnecting the power supply from  
the load and then testing the power supply?
To be on the safe side, you may want to shunt the output of the  
supply with appropiate load resistors before
you attempt this. say 15ohm for the 5 volt side and  25-40 ohms for  
the 12 volters. By the way last time I checked
EPR Electronics had drop in replacement power supplies, kinda pricey.
On Mar 22, 2006, at 10:04 AM, ted Summers wrote:

> Well, while Russ may be right, if you have the time, you could
> certainly pull those caps and try them on a DMM and see if they are
> shorted (although a capacitance tester would be a better bet, if you
> had access to one). You have nothing to lose but the time spent
> looking into it.... if a cap goes bad, it might take other
> components  with it. If my supply was dead, I would try and fix it.
> After removing the caps (especially if one was shorted), you could
> then start measuring points on the PCB to see if anything else
> appears shorted on the board. But that is just me....with 15+ years
> of working on electronics in industry, even without a schematic I
> could figure out what was wrong... then the question would be
> availability of the old part.... that would be the hardest thing to
> get potentially....
>
> You could also look for cold solders. When I replaced my LCD and
> floppy drive right after buying my Emax, I resoldered the complete
> power board to try and avoid future failure that could be caused by
> cold solders.....
>
> Weigh that with how much expertise you have. You could get an open
> frame PS that would do the job for about $30 if you know where to
> look. Some people have used a PC power supply (small form factor). I
> would have to look at my PS before I would commit to the PC way.....
>
> Thanks,
> Ted
>
> On Mar 22, 2006, at 2:51 AM, Russell Rose wrote:
>
>> hate to say it, but that is the suresign of a power supply gone
>> south, hope i am wrong.
>> that there are shorts( leaky bypass caps) across the 5 and 12 volt
>> rails all of a sudden
>> seems as likely as  maybe the cheshire cat playing croquet with the
>> Queen of Spades. and then winning.
>> On Mar 21, 2006, at 11:35 PM, synthmdl76 wrote:
>>
>>> I have seached the post and seen simular probs.  The leds and
>>> displace
>>> just flash but no power up.  The supply is just ticking and I
>>> think it
>>> may be a overcurrent protection cuase a cap is bad.  All my output
>>> voltages are messed up.  the +/-12 is at 8v and the 5 is at 3.5v.
>>> anyone seen this problem and know for sure what it may be?  I may
>>> just
>>> replace all the caps to see.
>>>
>
>
>
>