24 Jun
2013
24 Jun
'13
7:40 p.m.
On Mon, 24 Jun 2013, Jim Brain wrote:
Since I support the CBM crowd, I've had more than
a few people send me
comments over the past few years, asking when I might consider offering a
replacement power supply for the home computing machines (VIC-20, 64, 128,
+4)
Initially, I resisted for liability reasons and certification costs.
But, I decided earlier this year to put off those questions for a bit and
just see what might be technically and economically possible.
I've chased a few ultimately fruitless options, and I thought I'd see if some
fellow soul on this list might have some ideas.
Obviously, the first thought was a complete custom supply. My interest was
never in power design, so I am ill-equipped (and uncertain of my abilities)
to design such an item myself. Thus, I started looking for a manufacturer
that could design one.
Absolute requirements:
5VDC at 4.3A.
9VAC at 9VA unregulated
To this I added my requirements:
The 5VDC be a switching PSU output
ISO C13 input power jack (so I can support many areas without building custom
power cords
115/230 switchable design (or two very similar designs that can handle the 2
voltages)
My cost under USD$30.00 per unit.
Enclosed finished case, or be able to fit in a commonly available case
design.
Someone put me in touch with Stontronics overseas, which worked on an initial
quote. But, I think the C13 and 115/230 requirements scared them off.
I solicited information from Bear Power Supplies in the US, but they did not
seem too keen on continuing the discussion, so I have nothing from them.
I've also tried overseas suppliers, but I have not yielded fruit yet. I've
asked all the PSU suppliers on globalsources.com and alibaba.com
I have struggled to find a custom PSU manufacturer that can handle a suitable
design.
If you are open to considering either a C5 or C7 IEC 60320 coupler instead
of the C13, you'll probably have better luck with the PSU vendors. If you
don't need the ground/earth terminal (I can't see why it would be needed
for a replacement C64 PSU) a C7 will also cut the per unit cost and allow
for a smaller case.
Have you tried contacting Delta? In years past this sort of "unusual" PSU
would have been right up their alley, but they might require a large
production run. They can even build them where the casing is held together
with screws instead of being solvent welded together, making them easier
to service later (once the filter caps begin to dry out in a decade or
so). On that note, you would probably also want to specify that only
genuine, high quality 105C rated filter capacitors are to be used, from
either Nichicon, Rubycon, or Panasonic (and specify the series).