[Boatanchors] Interesting place to find HV and amp parts . . .

[Mike Andrews W5EGO]

On Wed, Feb 04, 2009 at 07:22:49PM -0500, James M. Walker wrote:
> Actually,
> the devices being spoken of cover a range from around 100 Khz
> to approximately 900 Mhz, in various power levels, with some
> really nice, and large power capabilities up to around 30 KW.
> 
> Here where I work, University Chemistry Dept. we have Mass Spec
> units that go down to the low end, and wafer coating gear that goes
> to the high end. One particularly fascinating unit is the 100 KW, 
> 480Khz unit, followed byt the 15KW (tunable) 13.56 unit.
> 
> For regular folks unfortunately these require three phase power
> and lots of it. However, in most units the driver sections are in the 1 KW
> range and make great amplifiers for the Amateur community, willing to
> make the necessary modifications to them. 
> 
> I have several pictures of the units here, if anyone is interested, or
> one can do a search on E-bay for RF Plasma, or ENI, or RFS, and
> see some other examples.

Back in 1964-67, a friend was doing PhD research on the calorimetry
of the refractory elements at very high temperatures. He'd heat up a
slug of Hafnium or Zirconium or Rhenium or Tungsten or some other thing
with a remarkably high melting or boiling point, all enclosed in enough
Argon to keep it from burning up. When it was as hot as he could get it,
he'd drop it into a Big Mucking Calorimeter and measure the temperature
change with time. He got numbers that corrected the then-accepted values
from NBS for a lot of different substances, and wound up working at NBS
shortly thereafter.

He used a _BIG_ GE induction furnace, with IIRC four 833s in parallel,
driving a water-cooled coil made of two opposing conical sections to
create a big whackin' field divergence in the center. Start the Ar
flowing, reach up from below with the slug in a quartz cup on a Long
glass rod, and push the START button. Withdraw the rod, and the slug
just hangs in the field, bobbing gently. Crank the DRIVE knob up and it
gets hot. And hotter. And MUCH HOTTER, until it's glowing blue-white and
the pyrometer says it's about 5000°-6000°F.

I think that rig ran in the low-HF ISM band, but I don't remember for   
sure. It's been a week or two, and I've slept. 

We discussed using that rig for supporting field and another one at VHF
for heating, but couldn't find vacuum capacitors that would handle the
RF current and that would fit inside his research grant money.

-- 
Mike Andrews, W5EGO
mikea at mikea.ath.cx
Tired old sysadmin