[AMPS] Re: skin depth suppression

[Rich Measures]

(Phil said:)
>.....snip.......the Henry suppressor that is
>used on the current 8K-Ultra and other models. I thought it was an ingenious
>idea, and I still do, although no one on the thread at the time seemed to get
>as excited as I did. For those of you who are not familiar with the
>suppressor,
>it is a 5 inch piece of brass strap bent into a one turn coil. The width
>of the strap and the diameter of the coil is 1 inch. The suppressor is then
>chrome plated to a depth sufficient to create the correct RS for the circuit
>for which it is intended.(a 3CX3000A7, in this case) The skeptics informed
>me that this was not chrome plating, but some other material. ...

(the eagerness of the skeptics/naysayers to proffer fabricated scientific 
evidence during the vhf parasitics debate never ceased to amaze me, 
Phil---and provided motivation for me to carry on---even though I was 
being privately advised to abandon by friends who were familar with the 
tactics of the Rauchian camp.)

>... I visited the
>Henry factory where it was indeed confirmed to be chrome. The advantages of
>such a device are obvious...at VHF, it looks lossy. At HF, it looks like a
>big, wide piece of brass strap. The RS is "built in," so there is no parallel
>resistor required to burn up on 10 meters, or fail during a fault. It does
>the job for which is was designed...it stabilizes the "system." The chrome
>plate is as beautiful as a car bumper for years! It has a little something 
>for everyone...the nichrome camp, the silver plated copper camp, and folks 
like I
>who truly admire a simple solution to a very complex problem. I don't know if
>this was an "in-house" Henry development, or from someone on the outside, but
>I would like to shake the man's hand some day!

The hand belongs to the legendary Mr. F. E. Handy, Phil---whose existence 
our self-recognized amplifier "expert" will not even acknowledge.  
 IMO, even though Henry's current 8k vhf suppressor design is better that 
what they originally used, a single-element plated suppressor can NOT 
provide the stagger-tuning effect that additionally decreases the VHF-Q 
of the anode-resonance.  With a single-element plated suppressor design, 
the L of Rs is identical to the L of Ls.  If a short length of resistive 
ribbon were connected across the ends of the one-turn Ls, a 
VHF-Q-decreasing R-increasing VHF stagger-tuning effect would result.   
  Another point:   Ch has 2x the volume-resistivity of Ag.  ..  ...  
Ni-Ch has  25x the volume-resistivity of Ch.  Thus, even through 
Ch-plating offers a 2x R-improvement over the Ag-plating that Henry 
originally used, additional R-improvement could be achieved by the 
switching from Ch to Ni-Ch.  Curiously, brass (Cu-Zn)  has about 1.7x the 
volume-R of Ch.   Who knows?  Maybe the next stage in Henry 8k suppressor 
enhancements will be to NOT PLATE the brass Ls.  
  IMO. (and at a consider risk of creating serious boredom in the 
naysayer's encampment),  adding even a small amount of ESR to Ls is 
useful.   Wes' scientific measurements of 
3-500Z suppressors indicated that a adding a few ohms of ESR in Ls 
lowered the VHF-Rp of the DUT from 166-ohms to 101 ohms... 
Rich---


R. L. Measures, 805-386-3734, AG6K   


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