>
>> >It sure had an effect on external "big bangs," band switch cooking, and
>choke
>> fires.
>>
>> ** a burned-band near the middle of a choke is usually from a vhf
>> parasite.
>
>All my choke fires have been HF related.
** This has been my experience too.
>Trying to use 5 band amp on
>a WARC band without dipping first.
>
** VHF-resonance related hv-rf-choke fires are seen mainly in Henry
Radio 2, 3-500Z amplifiers such as the 3K-A, 2K-4, 2K-3 ... ... . A
resonance near 95MHz appears to be the problem.
>> >IMO, the average ham with little test equipment cannot tell if an event
>> >was VHF,HF,or DC related at first glance. Most of us treat symptoms rather
>> than the
>> >disease because we have no idea what the cause was
>> >.
>> ** measuring the resistance of R-sup is a clue.
>
>I have never had an R-sup problem as all of mine are Carborundum units.
>
** The tradeoff with Carborundum/Globar ? units is that they have a bit
much intrinsic L for optimal VHF suppression service. To explain: To
exhibit good suppression, the inductances of the R and the L paths need
to widely different.
- R. L. Measures, a.k.a. Rich..., 805.386.3734, AG6K,
www.vcnet.com/measures.
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