As long as their current rating is high enough, it should be very safe. The
total current output will be of the lowest rated one. The voltage output
will be the sum of all that are in series.
I personally would go around to the various electronic suppliers and try to
get a 30 Volt supply, that is rated to at least 500 ma or more. This way
only one outlet will be used, and it is a more practical way to supply your
unit.
--
Jerry G.
=====
"Charlie Wilkes" wrote in message
...
On 06 Feb 2005 08:45:46 -0500, Sam Goldwasser
wrote:
"NSM" writes:
"Charlie Wilkes" wrote in message
...
Today I bought a well-used HP DJ 697c to print from DOS apps.
It came with no adapter. The label specifies 30 volts at 400ma.
I took an old plustek scanner 24v/600ma cube and a radioshack 3-12v
adjustable cube and wired them in series. I got 36v with no load, so
I figured that was probably about right. The printer powered up, but
after a few minutes the plustek power cube failed. The rshack cube is
still fine.
This group's FAQ reassured me that I wasn't doing anything too crazy,
but it mentioned a rectifier, which I don't have. I didn't get the
impression the rectifier was really essential, but I don't know much
about electronics.
Without knowing the details, it's hard to say what went wrong. What
were the exact ratings of the adjustable wall adapter? Many of those
are poorly constructed with limited current capability.
The requirement was 30v 400ma. All the cubes were rated at 600ma.
I felt wantonly destructive that night so I repeated the experiment,
this time with the surviving (3-12v adjustable) cube and two others
like it. I set two of them at 9v and one at 12v. Then I twisted and
I taped and I plugged it in and it works! I've had it going for a
couple of days now, printing away like a brand-new HP printer, which
is the price I paid for it with new cartridges. I just hope I don't
end up burning down another house.
Charlie
You might find one in a thrift or
http://www.allelectronics.com/cgi-bi...416&type=store
might be close enough.
Jameco usually has a pretty good assortment. www.jameco.com
--- sam | Sci.Electronics.Repair FAQ Mirror:
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