[FoxHunt] Ferrite antennas, nulls, 27 MHz.

[KD7JYK]

> Some of the 27MHz remote control, alarm, and pager equipment uses
> ferrite rod antennas in their receivers.

Thanks for the info, I recall seeing those in pagers I scrapped in the 80's,
these operated around 34 and 40 MHz.  I have several 27 MHz pagers, the few
I have opened have long wire antennas looped around the inside of the case.
One interesting unit, an explosion proof model made in the mid-60's has an
earphone to hear the page, two tone sequential, then voice and it uses the
earphone cord as the antenna.

> p.s. don't forget that as you approach a vertical antenna the field
> strength may actually drop as you enter the null of the radiation
> pattern off the end of the transmitting antenna (assuming it's up a
> mast).  Triangulating with a directional antenna is usually most
> fruitful than hunting on strength alone.

I forgot about that too.  I witnessed that in the early 90's when tracking
down a signal from a half wave vertical up 50', the signal got weaker as I
got closer to the antenna.  Right now all Ihave is my IC-706MKII, Kay
attenuator and a mixture of 27 MHz antennas so I am limited to signal
strength which has worked surprisingly well for two of the sources!

I guess I've been out of the game too long...  Now that I have found the
antennas, I know what to look for!

Kurt