I don't mean to whip a dead horse but I think a reasonable
power source besides batteries might interest a few on the
list besides me.... if my email is any indication. Here
is what I have found regarding power supplies as of now...
I had been advised that possibly placing two Astron power
supplies in parallel was an option to provide power to the
Herc II. I had called Astron and they stated that this
could be done and "generally" it would work fine. I
didn't really get an answer when I asked what "generally"
meant.
One of the engineering professors here at the college
where I work tells me (as did Astron) that it is critical
that both supplies provide the same voltage. Astron tells
me that you just adjust one supply to within 50 ma of the
other prior to hooking them up. The good professor tells
me that this might not be a good idea 'cause the amps will
differ their respective output under load and if not
closely matched under load may self destruct. He tells me
that laboratory supplies apparently have some way to track
one another so this doesn't cause problems. Astron tells
me that there supplies do not track. Anyone ever have a
problem with this ?
My other option (besides what appears to be the most
popular power source... batteries) is to utilize one of
the new generation of switching supplies. The supplies
being considered are made by IOTA and are available in 75
and 90 amp versions. On paper they look pretty good and
the mfg tells me they are purchased for use in
communications installations by Harris and others and are
generally considered to be RFI free in the ham bands. They
are allegedly filtered and bypassed for RFI. The IOTA
supplies are also sold to OEM's and re-badged and sold
under the names "Duracom" and "CAE" (cascade audio
engineering) among others.
The new IOTA 90 amp continuous switcher weighs 7.8 lbs and
draws a maximum of 21 amps @ full load at 108 volts (worse
case scenario) so if RFI free is quite the option for the
Herc.... especially at the $360 shipped price it can be
found at compared to the cheapest Astron dual supply price
of $560 shipped.
I found a third supply that is a linear supply and very
inexpensive at under $300. It's advertised as an 80 amp
supply and marketed by Okura USA under the name Nippon
America. However... it's instructions caution that the
amp is designed for "light duty" and one should be careful
using it at close to it's maximum ratings.... so much for
that one <grin>.
Is anyone using a IOTA, Duracom or CAE switcher on the
list that can comment on RFI?
Mike, W9WIS
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Michael Melland, W9WIS
Winneconne, WI USA
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