In: .com, wrote:
Do you have some sort of amplifier to go along with the loop? Some
antenna wire in a hoola hoop will work with a wellbrook ALA 100. One
loop is enough.. My preference is to use an "X" frame and build a
square loop because the hoola hoop isn't very rigid. However, for
something quick and dirty to set up, the hoop will work.

Really I just wanted to see one in operation. It's cool, maybe I'll build
another some day (I got 2 hoops, one slightly smaller, figured I'd "play"
with the idea of placing one inside the other and rotating it)

There are all sorts of tune loops you can build using circuits from the
ARRL handbook. The basic idea is to make a LC series circuit, then you
inductively couple the signal to a Jfet amp. I just find the notion of
having to tune the loop to be a PITA. I just wish there was a more cost
effective version of the Wellbrook.

Yea, tuning it is a pain. (I tried it with the variable cap. as well) turns
out the problem was in the long leads. Shorter leads made it work very well!
(Was actually able to get stations from other states during daytime hours!)

One problem though... the station I really want to get.. nothing comes in
on that freq. w/out the loop, but when I put the loop in, there are several
stations. Apparently, there are 3 or 4 of them, so, rotating it pulls in the
one on the OTHER side. :-/

Aside from that, it is a very fun toy, can't believe I could hear NPR on the
AM band. :-)

As far as the amplifier, some years ago... I built a regenerative receiver
(tube based) it was kind of a fun toy, I was thinking of doing something like
that for the amp, but based on this circuit:

http://www.tricountyi.net/~randerse/regen.htm

(resonant in the broadcast band instead of 40m as that circuit is designed)

One would imagine that "holding" the loop would make tuning nearly impossible, but...
wouldn't such an amp be really powerful? (Not such a good idea in places
like apartments though, lest one annoy the neighbors with RF pollution..)

Wonder if that circuit presented by Mr. Andersen could be powered via some
exotic means. :-)

Jamie
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