From: "Malcolm Watts"
Date: Mon, 21 May 2001 09:51:27 +1200
Subject: [TSSP] Re: Something of Interest
BTW, All resonators were run with an untuned primary of about 12uH
coupling into them at a about k = 0.1. Direct connection of the sig
gen to the coil base produced little of interest.
Malcolm
------- Forwarded message follows -------
From: Malcolm Watts
To: tssp@abelian.demon.co.uk
Subject: Something of Interest
Send reply to: M.J.Watts@massey.ac.nz
Date sent: Mon, 21 May 2001 09:16:54 +1200
Hi all,
Being the type to get bored easily when there is nothing to
do and not wishing to start a major series of expts (for which I'm
currently ill-equipped laboratory-wise at the moment), I played around
with a couple of resonators driven CW from a very low Z signal
generator and scope. Briefly, two of the resonators were around 20"
long, one with a diameter of 9" and the other about 4.5" (about 700
turns closewound), and the third resonator about 4" but wound with
about 1700 turns of rather finer wire. I don't have the details with
me at work so please forgive the lack of specifics. What I observed
will give rise to a series of expts and msmts when I get back from the
States. The generator is capable of 3VRMS with a source impedance of
0.5 Ohms resistive. Among other things, I noted a *drop* in Q when
placing a terminal on resonator #3 (usually one sees a rise and I
infer skin/proximity losses are most probably responsible due to the
small wire size) but of all three, this was the best radiator with no
terminal. I placed a 2' fluoro lamp on each resonator in turn and with
this particular resonator, the lamp lit for 3 or 4 resonant modes
(higher order). The lamp could be ignited by holding about 6" away
from the tuned coil and was still running 3' or so away with some
judicious retuning of the sig gen. There is some interesting data to
be mined out of all this and I expect some interesting running results
as well, both with and without terminals. I decided to flag this as I
won't have an opportunity to do anything about it for several weeks
and someone else on the list might. While conventional wisdom
concentrates on high secondary Q's, there is some really interesting
stuff to be gleaned from secondaries that pack a lot of L into a
relatively small volume. Tx line effects abound.
Regards,
malcolm
------- End of forwarded message -------
Maintainer Paul Nicholson, paul@abelian.demon.co.uk.