VT101 8085 CPU Fault

[Robert Jarratt]

> -----Original Message-----
> From: cctalk [mailto:cctalk-bounces at classiccmp.org] On Behalf Of
> js at cimmeri.com
> Sent: 16 February 2015 16:16
> To: General at classiccmp.org; Discussion at classiccmp.org:On-Topic and Off-
> Topic Posts
> Subject: Re: VT101 8085 CPU Fault
> 
> 
> 
> On 2/15/2015 5:24 PM, Robert Jarratt wrote:
> > I have checked the ESR on all the electrolytics, they are all fine.
> > Prior to all this I had replaced C439 with a higher voltage rated
> > component, as recommended here: https://trmm.net/VT100. I used a 100uF
> > part, rated at 100V. I had also replaced C437 as that had a high ESR
> > prior to seeing this problem.
> >
> > Is there anything else I should check?
> 
> ESR alone is not enough to validate
> capacitors.
> 


What other tests would you suggest? I do have a capacitance meter to check
values. I would have desolder them of course. Would you test just the
electrolytics or all of them? I don't have an insulation tester though. Any
other tests?

Regards

Rob