ORIGINAL MESSAGE:
On Fri, 2 Apr 2010 00:23:16 -0700, "Jim Thomson" <Jim.thom@telus.net>
wrote:
>## Not a chance Bill. Sure Myself, and everybody else does the
>same trick u do,,,, put a non inductive Resistor, between anode and chassis
>and the put the MFJ on the output, and activate the T/R relays.
>
>## Tune and load caps are then tweaked for flat swr on the MFJ. This
>procedure alone, doesn't help FINDING correct coil taps one bit !
>EG: I could easily have almost double the uh required for say 40m....
>and simply REDUCE the tune + load cap values.. till swr on mfj reads 1:1.
REPLY:
You say "not a chance Bill" and then you say you do exactly what I do.
What do you mean by "not a chance Bill"?
Second, when using the MFJ for this, the way I prefer is to preset the
tune cap for the value shown in the spreadsheets and then DO NOT TOUCH
it during the rest of the procedure. Adjust the load cap and change
the tap on the coil until you have the SWR 1:1. That way you end up
with the correct value of tune C and Q. Can't miss. Also, when
pre-setting the tune cap, be sure to have the tube anode connected so
it's capacitance is included too. If you are using a low frequency
C-meter such as the AADE unit, disconnect the plate choke lest it
throw the C measurement off.
73, Bill W6WRT
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