> I placed a 56 ohm resistor on the output, and a 1800 ohm
> resistor on the
> tube side of the pi-network - nothing changed. I re-read
> the e-mails, and I
> had used 12" ( 30.5 cm ) leads for both resistors - not
> good. On Monday, I
> will do it with very short leads. Tonight I have to grill
> !
>
>
Chuck,
You can shorten the leads and it won't help. The biggest dip
will come without any resistors.
You might try sticking the dip meter coil in towards the
axis of the coils. Also make sure the vacuum caps are
grounded to the chassis and all connections are solid.
Sometimes a little film or paint or clear coating can
insulate a ground, or you might have something anodized
(makes a good insulator).
The only path that matters is the loop around through the
tune and load caps and back through the coil. Imagine the
tune cap in series with the load cap, and then the coil in
series with them. That's the path that dips, and the reason
you do not need (or want) resistors. Resistors lower Q, make
the dip harder to see, and can mask an open loading
capacitor path. A dip test means only the tank MIGHT work,
not that it will.
If you want to do a resistor test, then you connect a
resistor from anode to ground and look into the pi net
output with an antenna analyzer. This is the ONLY test that
tests the tank components for matching.
You could have a non-working tank that dips fine, especially
with load resistance added.
You can't have a working tank that has a high SWR when you
look backwards through it when it is tuned right.
You also can't have a working tank if it does not dip at all
**without** resistors.
In this case you don't get a dip at all, and that does
indicate a tank problem.
73 Tom
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