I am new to this so hopefuly I can pose a intelegent question that
some kind of answer. Sence the thread seems to be running long the
line of input matching I thought now would be a good time to pose this
question. I have recentley become intrested in trying to building a
HF amp using the russian gs-35b. I have been told that the tube
charistics are similar to the 3cx1500 (8877). Based on the Arrl
hand book (76) construction artical the 8877 is quoted as having a
chatode impedence fo 54 ohns. I have not seen any Information on the
GS-35b that flatley states the chathode impedence for this tube is
X. I have looked through the handbook to see if I could find a
formula to calculate the input impedence based on bias operating
point or something similar to the formulas used to estimate the plate
load resistance. It would seem to me that there should be some kind
of relationship between bias , gain , drive level , input capitance or
something which would give a clue as to where to estimat the input
restistamce. I know that one of Wing field programs gives a set of
numbers for use of a pi input network on based on the expexted cathode
resistance of a triode.
--
FAQ on WWW: http://www.contesting.com/FAQ/amps
Submissions: amps@contesting.com
Administrative requests: amps-REQUEST@contesting.com
Problems: owner-amps@contesting.com
|