>>>Tom Rauch has given me some good possible suggestions for the
>>>suppressors. Perhaps I just need more inductance and a heftier R or
>>>something. Anyone else care to chip in an idea?
>>
What not use Mr. Rauch's unique technique for "neutralizing" a
grounded-grid amplifier?
>>
>>Been away on a long weekend so hope I'm not duplicating here.
>>
>>I seem to recollect suggesting the new 5W metal oxide resistors from
>>Mouser more than once Jon.
>
>Yes, I know. I've been considering ordering some. Are metal oxide and
>metal film resistors different?
Depending on the manufacturer, Metal Film [MF] is used below a certain
resistance, and Metal Oxide Film [MOF] is used above a certain
resistance. To increase R, the film is cut with a laser beam into a
spiral. . Unless one has access to a Z Analyzer, the best clue as to
likely performance of a film R in suppressor service is to scrape all of
the paint off the surface so that one can have a look at the resistive
film. If the spiral, if any, is one turn or so, chances are the the
intrinsic L is low enough to work satisfactorily in VHF suppressor
service. The 100 ohm Matsuchita film resistors we use in our suppressor
retrofit kits have roughly 11nH of intrinsic L.
>I've been considering looking into getting some fairly non-inductive
>resistors made by a company called Caddock Engineering. ......, their
resistor
>design has very low inductance and I figured that they might be a good
>way to go.
>
Measure the intrinsic L and you will know, Jon. I would like to know the
result if you do. . Cesiwid Corp. can custom make suitably low
intrinsic L resistors. The minimum order is around $10k (1k pieces @
c.$10 ea).
>>
Rich...
R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures
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