I don't know who wrote this, but I believe I see the fundamental error
which has led to so much confusion:
>>Follow this simple series of facts........
>>
>>1.) Rich claims a "low Rp" is desirable, and we both agree his
>>suppressor has lower VHF Rp than a stock suppressor.
>>
>>2.) A direct short has an Rp of zero ohms.
>>
_______________________________________________________________
When you say "A direct short has an Rp of zero ohms" there is the
error. A direct short IN THE SUPPRESSOR actually equates to an Rp of
INFINITE ohms. When the series resistor goes to zero, the parallel
equivalent goes to infinity, so the statement in #2 above is exactly
backwards. With infinite Rp, the Q of the parasitic tank circuit
becomes high, and oscillations become likely.
The reason Rich's suppressor has a lower Rp is because it has a HIGHER
series resistance, not lower, and certainly not a short.
Make sense?
73, Bill W7TI
--
FAQ on WWW: http://www.contesting.com/ampfaq.html
Submissions: amps@contesting.com
Administrative requests: amps-REQUEST@contesting.com
Problems: owner-amps@contesting.com
Search: http://www.contesting.com/km9p/search.htm
|