[AMPS] impedance of nichrome lower

[km1h @ juno.com]

Tom, I appreciate all your feeddback; it gets me a bit closer to
understanding.

Since your reply was so long, I will not reproduce it here. But a few
salient points:

The way I read Wes' report is that he wound the nichrome suppressor
himself, possibly from raw material supplied by Rich.....its not clear.

How many turns of wire are on the AL-80 suppressor?  Is the AL-82 the
same? The reason I ask is that most 3-500Z suppressors I am familiar with
are 2 to 3 turns since the parasitic is up in the 130MHz region. The 4-5
turn suppressors are more in line with 572B and similar tubes with
parasitics in the low VHF region. 

Wes also measured just the wire alone. Was this in coil configuration or
just straight wire?

Anyone who has worked at VHF/UHF knows that you do not use nichrome,
stainless or other materials with a high RF resistance....at any power
level. It kills the Q, and dissipates power.  So why would it not be a
good material to resist VHF energy in a HF amp?  NiCh60 has a 24% iron
content as well as Ni and Ch. If this is standard resistance wire at DC,
as used in meter shunts,  then why is it not performing the same function
at RF?   

The tests were run at the microwatt level, what happens at the KW level
with RF heating? 

Why was the ESR not listed for the AL-80 suppressor when it was for the
NiCh60? The omission is quite glaring to say the least.

The more I look at the "results" the more questions arise.  An ESR of 58
at 150MHz for the NiCh60 looks impressive to me.  With the hairpin loop,
the whole curve would just shift upwards and reduce the losses at 30MHz. 
A bit of fine tuning on an Impedance Analyzer  would be indicated here to
produce a better curve. 

The AG6K kit also includes 4 1 Ohm anode fuse resistors and an additional
pair of NiCh60 wires  for connection to the plate blocking cap. In all
fairness, since this is all in the kit, it should have been tested that
way.   

The ARRL is distancing themselves from all of this and refuses any
official comments. Just as they have distanced themselves from the
Maxwell issue.  Both issues have their own proponents at the League, just
as we do here but they are not at individual liberty to be open about it.
 At least we are discussing it, the ARRL  just play politics. 

I appreciate your offer of amps for independent testing. But would it
really be a fair test?  As you say the AL-80 is extremely stable as
should be any decent 3CX800 amp.  How about testing in a less than
perfect amp....SB-220, TL-922, LK-500, etc ?
After all Rich is selling retrofits to known problem amps...not good
ones. What about an early design AL-1200 since we all seem to agree that
was a hard one to tame? 

If you really want to push your luck we can try SB-200 and FL-2100's !  

If any testing takes place in New England I would love to be part of
it...just as an observer. 

I dont read Dejanews or any rec... stuff.  This takes up enough time. 

73 and Tnx again....Carl   KM1H

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