To: <amps@contesting.com>
> Date: Fri, 05 Jun 1998 20:41:52 +0800
> From: Alek Petkovic <vk6apk@faroc.com.au>
> I swept all frequencies from 18MHz up and stopped when I found a good
> positive dip at 32.2MHz. Sounds like a safe place to have a dip I think.
Hi Alek
Try this test. Drive the output port backwards with a bit of RF
watching SWR, and try tuning ONLY the tank (choke disconnected) for
low SWR (with the anode terminated in a few thousand ohms NON-
inductive or low inductive resistance).
Be SURE you put the lid back on.
If the tank doesn't tune, you have tank trouble.
If the tank does tune, and you connect the choke and it doesn't tune,
you have choke trouble.
A GDO does NOT measure impedance, and placing anything near the sides
of the choke greatly changes the resonant frequencies of the choke.
This is a much better test.
73, Tom W8JI
w8ji.tom@MCIONE.com
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