[Elecraft] Anyone know this info about switching supplies?

[Jack Brindle]

In the early 80s there was a video game manufacturer that had this  
exact problem - their power supplies would fail, placing 18 volts on  
the output, and thus frying the video logic. So, yes, it is quite  
possible for them to fail "full bore."

The company is no longer in business...

As a further note, the supplies showed up in Radio Shack sometime  
later where everyone who purchased one of the boards got to see the  
problem for themselves. At least R.S. was smart enough to label them  
as surplus...


On Nov 6, 2007, at 7:35 AM, Tom Hammond wrote:

> Folks:
>
> A local discussion has 'erupted' regarding switching poser supplies  
> and whether
> they can fail in an UNregulated (e.g. high) output voltage  
> condition, or if
> when they fail will they (almost) always fail in a NO OUTPUT mode?
>
> I think this discussion may have been started as a result of a  
> subject here on
> the reflector about overvoltage protection (OVP), but it's managed  
> to take on
> a life of its own with respect to the MODES in which a switching P/ 
> S can/will fail.
>
> Anyone have enough real experience to express their thoughts on  
> this subject.
>
> Must admit... I have no clue myself.  I've 'heard' that most  
> switchers fail in
> the NO OUTPUT mode, but this is strictly hearsay.
>
> Let's try to get several responses and the let the subject drop  
> before IT takes
> on a life of its own on the reflector and Eric has to step in...  
> he's busy enough
> right now. <G>
>
> 73,
>
> Tom   N0SS
>
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- Jack Brindle, W6FB
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