I'm in Richmond, Virginia and I'm trying to noticeably improve my
reception of WWV's 10MHz signal from Fort Collins, Colorado. It all
seemed so simple, two weeks ago: wind some wire, solder a
connector, and Hey...presto! a clean WWV signal. grin!

It wasn't so simple, and I'm afraid I've let it become an "ego
thing" (see also: resource sink). I've outlined the problem below
in the hope that someone can either suggest something I haven't
already tried, or even point out something really dumb that I've
been doing and shouldn't keep doing. grin!


Background
----------

Several years back I inherited a Heathkit GCW-1001 Most Accurate
Clock II from my father. This is an update to it's predecessor,
Heath's GC-1000 Most Accurate Clock; its circuit, built around a
Philips TDA1072A AM receiver IC and an 87C52 microprocessor,
monitors WWV's 10MHz signal and decodes the BCD-coded 100Hz
subcarrier (details at http://tf.nist.gov/stations/wwv.html) to keep
the MAC-II accurate.

This MAC-II worked fine for my father: he had a 30 meter dipole of
some kind in the attic, above the second floor of a house on a hill.
For him, WWV's 10MHz signal from Fort Collins came in regular as...
well, "clockwork". igg!

For me, in a one-story-plus-basement, in a low spot in a river
valley, it's a different story. The GCW-1001 has a stack-o-LEDs
signal strength indicator driven by the TDA1072's AGC output; it
would wander between 2 and 4 LEDs with my 40" indoor dangling wire
antenna, and it could take weeks or months for atmospheric
conditions to randomly improve the signal to where the GCW-1001
could "lock in" a time.

Two weeks ago, in a fit of madness, I decided to try building a
better antenna, one which would let the clock lock onto WWV at
least, say, once a week. The tuned-loop antenna I've built _has_
increased the signal -- I'm seeing 4-5 LEDs lit on a regular basis,
and 6 on occasion -- but the clock still isn't sync'ing to WWV's
time signal. The clock face remains at a cute(?) 7-segment "not
SEt" display. And what seems to be louder is the carrier -- or _a_
carrier, at any rate -- but not the tones or the human voice time
callout coming out of the GCW-1001's speaker.

I seem to be up to my assets in alligators, and the swamp doesn't
seem to be draining much.


Problem
-------

My main problem is that, although the GCW-1001's LED "Signal" stack
_says_ it's getting a stronger signal, what I hear through the
speaker monitor isn't _clearer_. There are long periods when I
cannot hear any WWV tones through the GC-1001's speaker, the
tones/ticks are faint even when there are 5-6 LEDs lit, and the
voice is almost never audible/distinguishable. The clock _seems_ to
be sync-ing a little more often (it's done it four times in the past
two weeks), but I had hoped it might happen a _little_ more
frequently.

Am I asking too much? Is WWV's 10MHz signal from (say) 2,000 miles
away, simply too weak to pick up solidly without an outdoor antenna?


What I've tried
---------------

My (second) attempt at a 30m indoor loop antenna:

Main loop (tuned): A 36" near-circle of #12 insulated house wire
with an AM/FM tuning capacitor across it.

Pickup loop: One (36") turn of #27 magnet wire taped to the #12
loop with electrical tapegrin!. The ends (scraped and tinned)
are tied to the GCW-1001's 50ohm antenna input with a couple of
12" clip leads and a 3' section of coax.

The loops are mounted on (and held in shape by) a 1'x4'x0.5"
"backboard" made of "blue foam" house insulation that I found in my
basement; the loops are held in place by small plastic cable ties.
The foam backing is resting against a (roughly) N-S wall, which
_should_ orient the loop plane across the WWV wavefront for maximum
pickup.

Does this sound like a reasonable attempt at a tuned 10MHz loop?

Is there any reason to believe that the foam backing would affect
the loop inductance? I'm assuming it's a good insulator and nothing
more, but that's an assumption.

Is it possible that I'm picking up a non-WWV dignal so strong that
it's masking WWV? I tried tuning around 10MHz with a shortwave
radio; it didn't find WWV -- not a particularly hopeful sign -- but
it did pick up a station called (IIRC) WWCR. WWCR's 'web site
(www.wwcr.com) lists its transmitter #4 as using 9.985MHz and
9.975MHz between 0900 and 2100 CST.

Any advice or suggestions will be appreciated, up to and including
"You can't power a hedge trimmer from two AAA cells!".

Thanks...


Frank McKenney, McKenney Associates
Richmond, Virginia / (804) 320-4887
Munged E-mail: frank uscore mckenney ayut minds pring dawt cahm (y'all)
--
Physics is mathematical not because we know so much about the
physical world, but because we know so little; it is only its
mathematical properties that we can discover.
-- Bertrand Russell
--