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[AMPS] Fw: parasites

To: <>
Subject: [AMPS] Fw: parasites
From: (skipp s isaham)
Date: Sat, 21 Jul 2001 19:10:23 -0700
Hello again,
It's not practical for me to go through the entire process 
of parasitic construction. To be honest, I don't think it's 
an exact perfect science and my opinions seem much 
different than many amps members. So I go my own 
way and have had very good results with my work. I 
just happen to have the benefit of very good test 
equipment to use. 
I'll try to dig out my suppressor construction file and 
detail some of the steps I used, but from memory only... 
I'll mention some of the high points here.  I don't wish 
to tie up a lot of time rehashing things that have been 
posted on here by many, subjects that are detailed on 
Rich's web site. Other information is available in the 
ARRL and Radio Handbooks.
The last "test sets" of SB-220 suppressors I constructed 
contained both Nichrome Ribbon and wire inductors in 
20 to 80nH values, across Rich Supplied 100 ohm 
3 watt MF resistors (the blue type). 
The most practical suppressor I now use in the SB-220 
is 40nH Nichrome wire wound in a coil, matched on 
the LC-102.  The ribbon did not appear to suppress the 
vhf response as well as wire.  I prefer the "lumped" 
wound coil vs the "hoop" coil option many use. 
I've tried 5/6 watt MF resistors with great luck and now 
use them in my suppressors. To be honest, I have not 
measured the "bare resistor" inductance, but like the 
3w resistors Rich supplies, the stray L appears 
relatively small in value. 
I also prefer the coil type inductance for size reasons, 
but avoid the resistor in the center location. Both sit 
happily in parallel adjacent to each other. 
: From: 2 <>
: What band and mode were you using when 
: R-supp burned out?  
: Did R-supp measure infinity  (?)  with an 
: ohmmeter or just changed R?
: tnx
The high end of the 10 meter voice band.  The old 
suppressors are actually still in one piece, sitting 
on my server desk.  I guess I'll measure one 
on Monday.  
: So the self-declared "expert" wants to know how 
: to determine how much L and R goes in a suppressor.  
: I published this info on AMPS.  If he was paying attention, 
: he would already know.   Will said that Rauch kill-filed me.  
: cheers, Skipp
:   R. L. Measures, 805.386.3734,AG6K 
: end
It would save me a lot of typing to include the above so 
Tom will see it and refer to the amps archives if he 
wishes to debate the topic with you again. 

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