Holy Cow!

The data sheet for the varactor diode claims less than 30pf to over
400pf with a 7v swing and Q of 200. Nice part - amazing part - how do
they fit all those plates inside there?

73
NEO



N9NEO wrote:
Good thread, and Nice call Telamon! The tuning mechanism by the radio
sends a voltage up to the unit by the loop. The unit by the loop has a
varactor diode inside. Sombody over in the other group said there is a
step up dc-dc converter to get from the 3 or so volts supplied by a
pair of AAA batteries to a voltage that the diode can use. I didn't
realize that a varactor diode could swing more than a few pf, so
thought that they wouldn't be very useful over the complete range the
thing is supposed to tune.

regards,
NEO


weatherall wrote:
Telamon Wrote:
I'm not familiar with this particular model but I would think that you
would want the tuner near the antenna.


This diagram explains the issue somewhat:
http://kaitousa.com/KA31.htm

The tuner is a small plastic enclosure including the power switch,
tuning dial, and the battery bay. It has a wire connected directly
that is around 21 inches in length, and the tuner has a jack on the
other side. The jack on the tuner is the same as the jack on the
antenna, and a much longer wire goes between them.

The diagram on Kaito's site indicates that the shorter,
directly-connected wire should make the connection to the radio (or
optionally the short wire with the black and white clips), and the long
wire should go between the tuner and the antenna.

This configuration allows the antenna to be hung wherever it will
perform best, while positioning the tuner close to the radio for
convenient operation.




--
weatherall