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Old October 31st 03, 03:00 AM
Ross Archer
 
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Diverd4777 wrote:

All:
Working on a ferrite antenna.

Ordered parts from Ocean state electronics, ( via website)

( http://www.oselectronics.com )

bought their 14-365 Pf variable capacitor and two ferrites:
one
FR4-33 #33 1/2" Diameter X 4" Long

and then

FERRITE "LOOP STIK" ANTENNA
band, 540KHz - 1600KHz. Measures 5/16" Dia. x 3 1/2" Long. Includes mounting
bracket and wiring diagram. Q=25, L=788µH.
LA-540...................

- Now, follow this :

I figure I'll use the 8 inch loopstick for the ' Primary" antenna. setting it
in a window..

Hook the " primary " up to the variable capacitor via about 10 feet of co-ax
wire.
- so I can Tune it from 10 + feet away.

THEN use the "FERRITE "LOOP STIK" ANTENNA"( part LA-540.)
as a " transmitter"
setting it on top of my sangean 606A;

- So the primary can be tuned from far away,
still usable via the capacitor and 10 + feet of wire..

- Any thoughts on this ? Sheer folley? Intellectual Property Theft? Genius ??

Happy as a Clam At High Tide..

Dan


Sounds like a great project! Like anything where there are
unknowns, experimentation is the fun way to go, so don't
hesitate to try different things.

The second, smaller ferrite to couple the signal into your
receiver is presumably in parallel with the 8" loopstick.
It's just that a bunch of coaxial cable is in-between.
Inductors in parallel have less inductance than either of
the two inductors, so this will throw you off using
equations built to serve the case of one loopstick and one
variable capacitor. This might cause you to need more
capacitance, which fortunately is easy to do by adding a
series of small caps in parallel until you achieve the
desired tuning range.

Someone else mentioned the extra capacitance added by the
coax. I'd *think* (I may well be all wet) that this extra
capacitance is a good thing given the partial loss in
inductance.