[Coco] [coco] video signal generation

[RJRTTY at aol.com]

In a message dated 1/5/07 3:28:57 P.M. Eastern  Standard Time, 
gene.heskett at verizon.net writes:
>>Y ou may want to  consider changing the electrolytic to ceramic if the
>> value is not to  high.  Albeit somewhat expensive, ceramic caps to about
>> 10 uF  are available.
>>
>I've not found them to be terribly dependable  James.  Very low tolerance 
>for any overvoltage.  The Panasonic  dvc-pro's had a few of those here and 
>there, and the failure rates were  about 20% of the teeny little surface 
>mount electrolytics around  them.  So we carried them on the shelf too.  
>Smallish qtys of  course, but then we were buying the electrolytics on 100 
>count tapes  toward the last of my tenure in that chair.  The electrolytic  
>failures were opens and high esr's, generally non-destructive, the  
>ceramics crowbared, so we noticed the destruction quickly.  Things  get 
>interesting when you have to figure out which trace in a 6 layer  board 
>goes where so you can jumper the burnout.  I gave up and  started 
>replacing the whole board after a while, it was  quicker.

>I could say do it, but use ones rated at least 2x the supply  voltage.  6 
>volters on a 5 volt line don't cut it for the long  haul.  

Well I am going to include the input filter since it does work even
if it is the cap on the GIME's supply line.  I have to build for  the
worst case situation were the cap is bad and the customer has
no interest in replacing it.
 
Also I have personally tried the converter on a half dozen different  machines
and have gotten feedback from customers and in every case the behavior  is
the same.   You would think that with random failures at least a  few would
still have good supply caps on the GIME.
 
Roy