Antenna for receiving WWV/10MHz: am I asking too much?
 

Rick wrote:
I am in New Jersey. Propagation from Colorado to here is probably similar to
Virginia.
This morning, Tues, 10/9, I listened to WWV on 10 MHz with the 4 antennas I
have at my disposal to see what kind of signal level I get.
My antennas are 80 meter and 40 meter dipoles, a 20 meter yagi and a 30 meter
dipole, all at about 50 feet.
On the first 3 antennas WWV runs about S6-9, and on the 30 meter dipole it is
10-20 db over 9.
This evening, 6 pm, the first 3 antennas haul WWV in at S9 and the 30 m
dipole has it at a rock solid 30 over.
So I agree with the advice you got to string up some kind of dipole and throw
out that loop, there is plenty of signal, you just have to go get it.

Rick K2XT

PS may I throw in a little commercial for my pet peeve? As you read this did
you notice that I did not include any text from previous posts? Did you miss
it?




-----------


Some of us include the previous post's text because we can't remember
what we're answering unless we can refer to it while writing.

You too will grow old someday, if you live so long. G


Ed Cregger, NM2K

Antenna for receiving WWV/10MHz: am I asking too much?
 

Frnak McKenney wrote:


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!

Frank, can't you erect anything outside at all? A 10 metre dipole, is after
all, only about 5 metres long. And if you can't do that, what kind of attic
do you have? If your house is oriented correctly, you could even build a
three element wire yagi pointed west inside the attic. Dimensions shouldn't
be that critical for receive only, and space the elements at about 2.5
metres. Basically one element at about 47 feet, one at about 49.3 feet, and
one at about 45 feet. Split the 47 ft one into two, feed it directly with
50 ohm coax, one side to the shield, one to the centre conductor, and you
have a three element wire beam pointed, hopefully, west. (Put the longest
element on the east side, the shortest on the west.)


Bob, VE7HS

Antenna for receiving WWV/10MHz: am I asking too much?
 

MK,

Hi. Thanks for taking the time to respond.

On Tue, 09 Oct 2007 03:06:18 -0700, wrote:
On Oct 8, 9:16 pm, Frnak McKenney
wrote:

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.

Sounds like it's being masked by some type of noise,
but this could just be from the signal being very weak.

If you can hear other stations ok, it probably the propagation
more than anything. Being that you can barely hear it on a
regular receiver seems to bear this out.

Sigh. So... there isn't some kind of cubist-wire-sculpture shape I
can bend my antenna into and magically make WWV appear? grin!

Unless a noise is local, and you are trying to null it, I see no
real advantage to using a small loop vs whatever else.

I constrained the problem by insisting on "indoor" and "small".
From your feedback, and my experience, it looks like I won't get
much further unless/until I'm willing to relax one of my
constraints.

I would make sure you don't have any local noise. IE:
powerline noise, etc. If you did, the loop would be a good
antenna to null that noise as long as you can turn it.
But if there is no local noise, and the noise you hear is
atmospheric, then it's not going to matter much what
you use.

I built a long-wire "antenna" last evening and I _thought_ my signal
picked up a bit... for a little while, anyway. I took a 100'
extension cord and unreeled it from the west end of the house to the
east end where the MAC-II is set up. On the floor. (Hardly a
"phased array"grin!, but I wanted to try _something_.)

I put the (plastic) reel with the rest of the cord up about a foot
away from my "loop", and I did seem to get a stronger signal
(translation: on the fade-ins it sounded a bit louder). I could
hear the "notes" fairly well at times and I could _almost_ make out
what was being said in the the voice segment. On the other hand,
this was somewhere around 1800, give or take an hour, and the signal
was fading in and out... it could have simply been due to
atmospheric conditions.

One good thing I learned was that I may have been tuning my antenna
incorrectly. It seems that there is a "roaring" that peaks the
GCW-1001's LED stack, but when I can distinguish the WWV tones and
maximize their loudness through the speaker I'm slightly _below_
that "roaring". In other words, I _have_ been mis-tuning, and
inadvertently helping drown WWV's signal out. Ouch. Wish I had an
accurate 10MHz signal generator; what I have is intended for audio
work and limited to about 1.5MHz.

I've got a hunch that the propagation is just the pits for
you right now.

Well, that's certainly a true description of what I'm experiencing
grin!, but I've had the MAC-II since 2004 and suffered the same
poor lock-in, and a MAC-I (GC-1000) a decade (ack!) behaved
similarly. 'Course, I used its built-in whip (something the MAC-II
lacks); I didn't build _it_ an antenna of its very own. grin!

I wouldn't be surprised if you tried it in a couple of months
and it worked ok.. If you hear it on the regular radio ok,
the clock should too. If you can't hear it on the regular
radio, the clock probably won't either, and there is
probably not much you can do about it.

I was afraid of that. I suppose I could build a battery-powered RF
amplifier and stick it on the antenna, but the trick (stop me if
you've heard this one grin!) is to make just-the-stuff-I-want
louder. Making _everything_ louder doesn't help me.

There should be times that it comes in fairly decent though,
depending on time of day, etc..
I would use what you hear on the regular receiver as to
whether the signal is really there or not.

You're probably right. Means I have to clear off some more lab
bench space next to the MAC-II, and I should probably re-tighten the
dial cord on the Mohican and dust off its tuning capacitor plates.
grin!

This may wind up being a classic example of the "DIY-DYI
Transformation": a "really neat" do-it-yourself idea which started
out simply enough, but which has somehow turned into a
must-complete, spare-no-expenses Do-Yourself-In Project. grin?

Propagation on most of the HF bands has been fairly
flaky the last few months. IE: I got on 40m in the daytime
the last time I was in OK, and it was like I was on 20m..
Band was real stretched out, and pretty long skip zones.
I'd miss the semi locals I'd usually talk to, and end up
hearing stations 1000 miles away instead.

So... if I ran this really long piece of coax out to Oklahoma, then
I could pick up Fort Collins really well via skip? I've got a bunch
of A/V 75ohm stuff, and some old T-Base2 Ethernet cables; that's a
start... (Riiiight! grin!)

I think it's time to step back and think about what I've discovered
and learn a bit more theory; my ARRL Antenna Handbook (1991ed)
arrived in yesterday's mail, so I'll be learning from The Source.
(I sent my brother Bruce an e-mail message a few days back
explaining why antenna length mattered; it made sense at the time,
but I may have to revise it after some more reading.)

And, if I decide I need a radio-based time source before I can get a
good WWV signal, I could always hack a WWVB clock -- as long as it
had a dead LCD panel or something: I have this weird reluctance to
tear apart anything that is still working. grin!

Assuming, of course, that I can pick up WWV_B_ here. grin?

Anyway, thanks for reassuring me that my poor WWV reception really
might not be due to a poor antenna design. If I ever come up with a
Really Good Solution I'll post back here.


Frank
--
Do not follow where the path may lead. Go instead where there is
no path and leave a trail. -- Ralph Waldo Emerson
--
Frank McKenney, McKenney Associates
Richmond, Virginia / (804) 320-4887
Munged E-mail: frank uscore mckenney ayut minds pring dawt cahm (y'all)

Antenna for receiving WWV/10MHz: am I asking too much?
 

Frnak McKenney wrote:
Anyway, thanks for reassuring me that my poor WWV reception really
might not be due to a poor antenna design. If I ever come up with a
Really Good Solution I'll post back here.

What would help you is an outdoor active antenna. For a start look at MFJ's.
It's a metal box with an amplifier in it, and a whip antenna. It uses a
small box at the receiver end to pass DC up the coax to power it.

Placing it outside would help. Placing it outside and away from noise
sources, or on the roof would help more. A whip antenna is used because
it's a cheap commerical off-the-shelf (COTS) item. It could be replaced
with a thin wire. The coax could be replaced with a run of (more expensive)
mini-coax. This would make it easier to hide and you may be able to use it.

If you are handy with building things, there are lots of designs for similar
devices, the easiest is a single MMIC type amplfier. It may be more difficult
to actually do as they are very sensitive to static.

If all you have is a window, a loop around it would do. If it has a metal frame,
and all 4 sides are connected to each other, you can try using it as a loop.
If not, thin wire held up by transparent tape, or that metal tape used by
alarm systems would work.

Geoff.

--
Geoffrey S. Mendelson, Jerusalem, Israel N3OWJ/4X1GM
IL Voice: (07)-7424-1667 U.S. Voice: 1-215-821-1838
Visit my 'blog at http://geoffstechno.livejournal.com/

Antenna for receiving WWV/10MHz: am I asking too much?
 

On Tue, 09 Oct 2007 02:16:37 -0000, Frnak McKenney
wrote:

Am I asking too much?

Hi Frnak,

Judging by the questions and responses, I would have to say "Yes."

To this point you haven't exactly demonstrated you have a problem,
just a complaint of a signal of poor quality to a human's perception.
For the clock itself, that complaint is arguably weak.

Let's just examine the evidence for the problem: There is none!

You have a clock that has 100mS resolution, and yet you have never
said how much it is off. 100mS? 1S? 10S? 1 minute? 1 Hour? All,
or any part of any of these metrics?

As Reggie would have chimed in at this point "If you can't measure it
and express it with a quantifiable, then you don't know anything."

Of course, your only source of accurate information is the one you are
suggesting has a problem. It probably doesn't have a problem, but
then how does one use this source's accuracy to check itself? You
would need a second clock to check it, and we would be hearing your
complaint in stereo.

I've calibrated time standards to the nearest 100nS and it is
accomplished at one sitting, no need for total connectivity such as
you might imagine (unless the clock you have is especially crappy).

Your clock has a resolution of 0.1 second. There are roughly 1
million ticks of the display in a day. A simple XTAL oscillator at 10
MHz would exhibit 50ppm stability and in a day wander up to 0.5
second. The next day it might wander back, the day following it might
slip below by 0.5 second. You would be hard pressed to confirm this
with over the air matching to the strike of the WWV gong - except if
the clock is especially crappy (and it could be). The same XTAL might
also exhibit an absolute error of 50ppm and accumulate time error.
This would be far more noticeable over the course of a week (you could
confirm the error by listening to time announcements - but you have
been silent to this issue).

These worst case errors all presume that the internal circuitry cannot
over the course of 24 hours manage to pull out one of 1400
synchronizing opportunities to phase lock out the error. These
circuits are generally optimized to accomplish just this (they work
fine in watches with a 60KHz signal after all). Your clock may be
especially crappy (but that is unlikely).

The clock synchronizing circuits don't have to listen to the bandwidth
of noise you hear, the speaker is for your convenience, not the
clock's. I am sure that it works fine with only 1 LED lit - this is
not a case of "can you hear me now?"

73's
Richard Clark, KB7QHC

Antenna for receiving WWV/10MHz: am I asking too much?
 

Ed Cregger wrote:
You too will grow old someday, ...

.... and forget to click the send button only once? :-)
--
73, Cecil http://www.w5dxp.com

Antenna for receiving WWV/10MHz: am I asking too much?
 

I'm just trying to be helpful, not a wiseguy. Although it does seem that my
genetics predispose me to lean in that direction. G

Ed, NM2K


"keithm" wrote in message
...
Since he said previously that he could hardly hear the tones/voice, isn't
it probable that the receiver is just seeing mostly noise?

As mentioned by someone else, propagation is currently "very ordinary"
(aka poor) at present, so maybe he's just out of range.

KeithM
VK1ZKM

"ecregger" wrote in message
...

"Owen Duffy" wrote in message
...
Denny wrote in news:1191956444.157030.11580@
22g2000hsm.googlegroups.com:

The other issue is whether your clock is actually able to synch with
the WWV signal... You may have a defect in the clock... It would seem
that 4 or 5 bars should have done the trick...

Presumably the LED meter indicates recieved power, not signal to noise
ratio.

Owen


--------


That's good!

Polarization was one of my thoughts.

Also, how is the synch tone derived by the receiver? Maybe that part of
the radio needs tweaking? One would think that seven segments out of ten
should be sufficient. I'm assuming there are ten segments total.

Ed, NM2K

Antenna for receiving WWV/10MHz: am I asking too much?
 

G

New computer, new software and fasciculations. What a combo!

Ed, NM2K


"Cecil Moore" wrote in message
...
Ed Cregger wrote:
You too will grow old someday, ...

... and forget to click the send button only once? :-)
--
73, Cecil http://www.w5dxp.com

Antenna for receiving WWV/10MHz: am I asking too much?
 

Denny,

Thanks for joining in.

On Tue, 09 Oct 2007 12:00:44 -0700, Denny wrote:
On Oct 9, 6:06 am, wrote:
On Oct 8, 9:16 pm, Frnak McKenney

wrote:

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 ...
--snip--
Sounds like it's being masked by some type of noise,
but this could just be from the signal being very weak.
If you can hear other stations ok, it probably the propagation
more than anything. Being that you can barely hear it on a
regular receiver seems to bear this out.
--snip--

Even with my antennas on a 150 foot tower there are times of day
when WWV at 10 megacycles is not audible... This is just the way
the daily propagation cycle is at 30 meters.

Grumph! (but the 150' tower impresses me! grin!)

My best advice is to put up a dipole for 30 meters, even if you have
to bend the ends to make it fit your space...

Well, a halfwave 30m dipole comes out to... 49 feet?

I went back and checked the NIST "Time and Frequency Services" PDF
file. According to this, WWV-10MHz comes off "half-wave vertical
antennas that radiate omnidirectional patterns."

Maybe I can wind my two 24.5' wires into vertical-axis helices?
grin!

... A horizontal dipole
being balanced picks up less vertically polarized noise than
vertical antennas... Getting the wire outdoors will help also...
You are likely picking up lots of humm and buzz inside the building
from various electrical and electronic devices...

Not sure what you could be referring to... other than the three
computers, 25" monitor, printer, Atmel AVR development board (8MHz
clock), flourescent desk lamp, and overhead I-look-like-an-
incandescent flourescent helix... all within 3 feet of the antenna
and clock. grin!

The other issue is whether your clock is actually able to synch with
the WWV signal... You may have a defect in the clock... It would
seem that 4 or 5 bars should have done the trick...

If it _never_ sync-ed I'd be strongly leaning toward your way of
thinking. In the past, with a "dangling wire" antenna, it has
occasionally taken months to get in sync; with my two loops I've
managed to get it in sync three times (IIRC) in the past two weeks.
(If I were still rational on the subject, I'd just admit that I
_have_ seen improvement -- all the way from "completely
undependable" to "approaching acceptable" -- even if it's not quite
as much as I'd hoped for.)

Thanks again.


Frank
--
The cure for boredom is curiosity. There is no cure for
curiosity. --Ellen Parr
--
Frank McKenney, McKenney Associates
Richmond, Virginia / (804) 320-4887
Munged E-mail: frank uscore mckenney ayut minds pring dawt cahm (y'all)

Antenna for receiving WWV/10MHz: am I asking too much?
 

Owen,

Thanks for the comments.

On Tue, 09 Oct 2007 19:58:10 GMT, Owen Duffy wrote:
Denny wrote in news:1191956444.157030.11580@
22g2000hsm.googlegroups.com:
The other issue is whether your clock is actually able to synch with
the WWV signal... You may have a defect in the clock... It would seem
that 4 or 5 bars should have done the trick...

Presumably the LED meter indicates recieved power, not signal to
noise ratio.

Exactly. It's an LED bargraph driven by pin 9 on the TDA1072A chip;
according to the data sheet that's the "Field strength indicator
output", a log-scale output driven by the internal AGC amplifier.

I got a clearer WWV signal the other day and was able to re-tune my
antenna. It turns out that the "loud signal" I was tuning to wasn't
WWV, just some random RF I was overloading my poor clock with. The
bargraph now sits down at 1-2 LEDs most of the time, although I did
see a "bursty" period this morning where it went up to 3-5 LEDs.

The WWV audio was coming and going on about a five-second interval:
louder (almost clear), then softer (almost to disappearing), then
louder again. "Wow", so to speak. grin!

Ah, well. Maybe in my Copious Free Time I'll replace the MAC-II's
87C52 with something I understand, like an AVR, and program it _my_
way. (Oh. Then _I_ get the support calls. ... Ack!)


Frank
--
"Curiosity is one of the permanent and certain characteristics
of a vigorous mind. -- Dr. Samuel Johnson
--
Frank McKenney, McKenney Associates
Richmond, Virginia / (804) 320-4887
Munged E-mail: frank uscore mckenney ayut minds pring dawt cahm (y'all)