On Wed, 28 Jan 2009 20:19:20 GMT, "Jerry"
wrote:

Hi Richard

I made a capacitator rotator for my 6 foot AM loop using a hobby shop
servo to rotate the air variable cap. It works quite well and the
components are affordable.
The 3 section air capacitor allowed the use of each section by switching
to the appropriate section with a TO-5 relay.

That is Brute Force to tune an AM loop, but sure makes sense and uses
affordable parts.

Jerry KD6JDJ


Hi Jerry,

You have certain advantages over most of the correspondents here. You
are something of a gear head, you know where to find things, you know
how to put them together, and you actually do it.

When I was a kid, I had the same bent, but my resources were from
government surplus when you needed 400Hz 26V supplies (or other such
oddities). It was back in the 60s when I started experimenting with
Varicaps except they were 1N23 style diodes sold for their Varicap
properties (which comes free with almost any diode); the real Varicaps
sold for far too much for my allowance. Wasn't much tuning ratio back
then either - about 3:1 to 5:1 - today's have more range than most air
caps.

73's
Richard Clark, KB7QHC