Jim, et. al.,
For HV insulated wire go to a neon sign company. They typically have
rolls of very wiring in 14 gauge with 15KV insulation or better. I was given
some 3 foot scraps from a field installation for rewiring inside a Drake L7
power supply. By the way, I have not found a connector good for more than 3
KV. The Millen unit can leak around the HV wire at higher voltages. I
would put a gromet in a chassis panel hole and pull the wire through to a
well insulated terminal strip at each end.
Yes there is some heat, so I would use a low volume fan to vent air out
of the power supply area. Don't forget there is resistance in the plate
transformer windings, some voltage drop in the diodes, and you will have a
bleeder resistor across the filter capacitor, and maybe equalizing resistors
if you are using a string of electrolytics. For example, Alpha has always
drawn air past the power transformer to the front of the cabinet and then
through the RF deck to the fan that cools their tube(s) in all of their
Alpha 374, 274, 76, 77, 78, and newer models.
Good Luck 73, George K8GG
----- Original Message -----
From: "Jim Isbell" <millenniumfalcon@cableone.net>
To: "Mail list Amplifiers" <amps@contesting.com>
Sent: Sunday, June 29, 2003 10:07 AM
Subject: [Amps] Power supply design considerations
> I am still working on the 4-1000A amplifier design and have decided to
> separate the PS from the RF chassis. I still don't have my HV
> transformer but I am thinking that it will be too big to get into my
> presently designed cabinet of 14" x 14" x 12" dimensions along with the
> 4-1000A and all the plate tuning circuitry and filiment transformer.
>
> I will be putting the power supply under the bench in a built in (wood)
> cabinet that is already there. The PS chassis/cabinet itself will be
> made of aluminum but it will set on a shelf inside a closed door so I am
> wondering about wheather I will have to wory about heat build up? It
> will be solid state diodes, capacitors and transformer. Do I need to put
> in a fan in the side of the cabinet?
>
> The second item I am asking for design help on is the power cable to the
> RF chassis. This will run about 6 feet from the under desk cabinet to
> the top of the desk through a hole in the bench. It will be near my
> knees so I dont want it to arc (5 Kv) to any part of my body.....#8-)
> What should I use for transmission cable? What is a source for such
cable?
>
>
>
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>
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