I have a 12 volt power supply that converts 110AC to 12V DC (actually 13.5.)
I haven't used it for some time.
I was using it to check some wiring and find it is now putting out 21 VDC.
???
ds


--
THE WORLD WILL END TONIGHT AT 9 O'CLOCK!
(9:30 in Newfoundland.)

The voltage regulator circuit is defective. It is also possible that the
output transistor, or device in the supply is shorted in some way.

You will need some troubleshooting and servicing skills, and the sources for
the parts, to fix your power supply. If your supply uses common generic
parts, these can be purchased from any of the generic electronics parts
suppliers. If you have to send it out, this would not be cost effective,
since they are not expensive to buy.

--

JANA
_____


"DS" wrote in message
t.ca...
I have a 12 volt power supply that converts 110AC to 12V DC (actually 13.5.)
I haven't used it for some time.
I was using it to check some wiring and find it is now putting out 21 VDC.
???
ds


--
THE WORLD WILL END TONIGHT AT 9 O'CLOCK!
(9:30 in Newfoundland.)

Hello, DS!
You wrote on Mon, 8 Aug 2005 08:43:53 -0400:

D I have a 12 volt power supply that converts 110AC to 12V DC (actually
D 13.5.) I haven't used it for some time.
D I was using it to check some wiring and find it is now putting out 21
D VDC.
D ???
D ds

Wouldn't be that unusual without a load. But it does seem a bit high, Is the
reservoir smoothing cap OK? If it goes open you might get a high reading
with lots of ripple.


With best regards, 3T39. E-mail:

"DS" writes:

I have a 12 volt power supply that converts 110AC to 12V DC (actually 13.5.)
I haven't used it for some time.
I was using it to check some wiring and find it is now putting out 21 VDC.
???

As someone else noted, check it under load. But if it is the typical
Radio Shack or similar "12 V" power supply, then it probably is a regulator
problem, possibly just bad solder connections or a shorted transistor (though
that wouldn't happen from sitting around).

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(Michael Black) wrote:

...
And ironically, you might find that the smaller the capacity the
more the platters.

That might be interesting trivia if it were true.

http://westerndigital.com/en/product...asp?DriveID=85

Click on the Configuration tab for each of the sizes and look at a
number of platters.

If you can find data for a series which supports your contention,
please post the link.

But technology is changing so fast that indeed, a drive that appears
similar on the outside may have a different bit density on the platters.

On 08 Aug 2005 11:07:27 -0400, Sam Goldwasser wrote:

"DS" writes:

I have a 12 volt power supply that converts 110AC to 12V DC (actually 13.5.)
I haven't used it for some time.
I was using it to check some wiring and find it is now putting out 21 VDC.
???

As someone else noted, check it under load. But if it is the typical
Radio Shack or similar "12 V" power supply, then it probably is a regulator
problem, possibly just bad solder connections or a shorted transistor (though
that wouldn't happen from sitting around).

but using it for "testing wiring" may have applied a short and let the smoke out
of the series reg device ...