[time-nuts] 60kHz Loop antenna

J. Forster jfor at quik.com
Sun Oct 3 18:02:28 UTC 2010 

As I remember, the WWVB waveform is a 60 KHz sine wave, slowly AM
modulated, <100%, for a digital time code. Every hour there is a 45 degree
phase shift between xx:10 and xx:15.

If you plot the phase out from a receiver, the trace will look like a
straight line with 1/12 duty cycle pulse. The slope of the line give the
difference between your local standard and the WWVB one.

My concern with tuning the loop is that as the tuned circuit drifts with
temperature, or other things, an extraneous phase shift will be intoduced 
to the received signal. Remember, the phase of a complex pole pair tuned
circuit goes from +90 to -90 degrees as you sweepo through resonance. The
higher the Q, the steeper this effect would be.

I expect, but am not certain, that the HP and similar amps would be double
tuned for a "rabbit ears" bandpass response that has flat phase through
the bandpass.

FWIW,

-John

=================


> John - It has been a while since I have seen the waveform. What is the
> rate
> of change of phase per unit time? Or, the occupied BW? Thanks - Mike
>
> Mike B. Feher, N4FS
> 89 Arnold Blvd.
> Howell, NJ, 07731
> 732-886-5960
>
>
>
> -----Original Message-----
> From: time-nuts-bounces at febo.com [mailto:time-nuts-bounces at febo.com] On
> Behalf Of J. Forster
> Sent: Sunday, October 03, 2010 11:29 AM
> To: Discussion of precise time and frequency measurement
> Subject: Re: [time-nuts] 60kHz Loop antenna
>
> Since WWVB is a phase tracking system, I'm not convnced a high-Q loop is
> such a good idea. HP's loop for the 117A is not tuned, as I rember, but it
> is followed with a narrow band amp.
>
> FWIW
>
> -John
>
> ===========
>
>
>> Thanks Dick, Ok with interference that close it would help. Shielding
>> doesnt
>> always provide much at these frequencies and can reduce the Q of the
>> loop.
>>
>> Best Wishes
>> Alan G3NYK
>>
>> ----- Original Message -----
>> From: "Dick Moore" <richiem at hughes.net>
>> To: <time-nuts at febo.com>
>> Sent: Sunday, October 03, 2010 6:56 AM
>> Subject: Re: [time-nuts] 60kHz Loop antenna
>>
>>
>>> Alan, I did try a real half-a$$ed pile of wire and a tuning cap. My
>>> shop
>> has fluorescent lights and I got a lot of noise. Once I built the
>> shielded
>> loop and got it lined up with east and a little south (I'm in Washington
>> State), WWVB came in gang-busters. This was before I built a GPSDO or
>> two
>> and then got a TBolt.
>>>
>>> The shielded loop has just been sitting for years.
>>>
>>> Dick
>>>
>>>
>>> On Oct 2, 2010, at 3:42 PM, time-nuts-request at febo.com wrote:
>>> >
>>> > Message: 5
>>> > Date: Sat, 2 Oct 2010 23:40:52 +0100
>>> > From: "Alan Melia" <alan.melia at btinternet.com>
>>> > Subject: Re: [time-nuts] HP/Dymek DY-5842
>>> > To: "Discussion of precise time and frequency measurement"
>>> > <time-nuts at febo.com>
>>> > Message-ID: <015501cb6283$10071ad0$4001a8c0 at lark>
>>> > Content-Type: text/plain; charset="iso-8859-1"
>>> >
>>> > Dick did you ever try an unscreened loop ?? they should be just as
>>> good
>> if
>>> > not better at 60kHz.
>>> > Alan G3NYK
>>> >
>>> > ----- Original Message -----
>>> > From: "Dick Moore" <richiem at hughes.net>
>>> > To: <time-nuts at febo.com>
>>> > Sent: Saturday, October 02, 2010 11:22 PM
>>> > Subject: Re: [time-nuts] HP/Dymek DY-5842
>>> >
>>> >
>>> >> I used to have one of these marvelous receivers and sold it. I still
>> have
>>> > the WWVB/60kHz shielded loop antenna that I made for it and although
>>> it
>> is
>>> > big, at about 30" x 30" x 2" or so, I believe it will ship FedEx or
>>> UPS
>> OK.
>>> > It's free to anyone who'll pay the shipping. It's made out of copper
>> pipe
>>> > and works quite well, and is tuned for the 5842 at 60kHz.
>>> >>
>>> >> Best,
>>> >> Dick Moore
>>> >>
>>> >>
>>> >> On Oct 1, 2010, at 3:50 PM, time-nuts-request at febo.com wrote:
>>> >>
>>> >>
>>> >>> Message: 5
>>> >>> Date: Fri, 01 Oct 2010 16:34:57 -0600
>>> >>> From: ziggy9 <ziggy9 at pumpkinbrook.com>
>>> >>> Subject: [time-nuts] Possibly OT - Any interest in a vintage
>>> HP/Dymec
>>> >>> DY-5842 VLF receiver?
>>> >>> To: <time-nuts at febo.com>
>>> >>> Message-ID: <990bd60b3c5d084910c10c8855912ddf at pumpkinbrook.com>
>>> >>> Content-Type: text/plain; charset=UTF-8
>>> >>>
>>> >>>
>>> >>> Fellow time-nuts:
>>> >>> I've got a circa 1964 DY-5842 VLF receiver. This is (was) operated
>>> in
>>> >>> conjunction with an external time interval counter to make a
>>> frequency
>>> >>> comparison. So you would select WWVL for example, and use that as
>>> your
>>> >>> primary standard for comparison to your local standard. It's got 5
>>> > crystals
>>> >>> in it: 16, 18, 19.8, 20, and 60 kHz (listed as GBR, NBA, NPM, WWVL,
>>> > WWVB).
>>> >>> It works and I have the manual. The thing is, the interest in
>> something
>>> >>> like this is bound to be a bit narrow, so I thought I'd mention it
>> here.
>>> >>>
>>> >>> So if there are any collectors, equipment museums, etc. that might
>>> be
>>> >>> interested in this, please let me know. I'm a bit sentimental about
>> this
>>> >>> thing, it's sort of a bit of history, and from what I can tell,
>> somewhat
>>> >>> rare (doesnt make it worth anything though :). Since it's a bit of
>>> a
>>> >>> curiosity, I'd like to pass it to someone that might be interested
>>> in
>> it
>>> >>> rather than just tossing it. I can always provide more details to
>> anyone
>>> >>> that wants them.
>>> >>>
>>> >>> Best regards,
>>> >>> Paul Davis - K9MR
>>> >>>
>>> >>>
>>> >>>
>>> >>>
>>> >>> ------------------------------
>>> >>>
>>> >>> Message: 6
>>> >>> Date: Fri, 1 Oct 2010 18:42:16 -0400
>>> >>> From: "jmfranke" <jmfranke at cox.net>
>>> >>> Subject: Re: [time-nuts] Possibly OT - Any interest in a vintage
>>> >>> HP/Dymec DY-5842 VLF receiver?
>>> >>> To: "Discussion of precise time and frequency measurement"
>>> >>> <time-nuts at febo.com>
>>> >>> Message-ID: <B7EA2D4AB6F34AB19DA25CFDC85A666A at Franke>
>>> >>> Content-Type: text/plain; format=flowed; charset="iso-8859-1";
>>> >>> reply-type=original
>>> >>>
>>> >>> I am very interested.  Do you have any images?
>>> >>>
>>> >>> John  Franke WA4WDL
>>> >>> Portsmouth, VA 23703
>>> >>>
>>> >>> --------------------------------------------------
>>> >>> From: "ziggy9" <ziggy9 at pumpkinbrook.com>
>>> >>> Sent: Friday, October 01, 2010 6:34 PM
>>> >>> To: <time-nuts at febo.com>
>>> >>> Subject: [time-nuts] Possibly OT - Any interest in a vintage
>>> HP/Dymec
>>> >>> DY-5842 VLF receiver?
>>> >>>
>>> >>>>
>>> >>>> Fellow time-nuts:
>>> >>>> I've got a circa 1964 DY-5842 VLF receiver. This is (was) operated
>>> in
>>> >>>> conjunction with an external time interval counter to make a
>> frequency
>>> >>>> comparison. So you would select WWVL for example, and use that as
>> your
>>> >>>> primary standard for comparison to your local standard. It's got 5
>>> >>>> crystals
>>> >>>> in it: 16, 18, 19.8, 20, and 60 kHz (listed as GBR, NBA, NPM,
>>> WWVL,
>>> > WWVB).
>>> >>>> It works and I have the manual. The thing is, the interest in
>> something
>>> >>>> like this is bound to be a bit narrow, so I thought I'd mention it
>>> > here.
>>> >>>>
>>> >>>> So if there are any collectors, equipment museums, etc. that might
>>> be
>>> >>>> interested in this, please let me know. I'm a bit sentimental
>>> about
>>> > this
>>> >>>> thing, it's sort of a bit of history, and from what I can tell,
>>> > somewhat
>>> >>>> rare (doesnt make it worth anything though :). Since it's a bit of
>>> a
>>> >>>> curiosity, I'd like to pass it to someone that might be interested
>>> in
>>> > it
>>> >>>> rather than just tossing it. I can always provide more details to
>>> > anyone
>>> >>>> that wants them.
>>> >>>>
>>> >>>> Best regards,
>>> >>>> Paul Davis - K9MR
>>> >>>>
>>> >>>>
>>> >>>> _______________________________________________
>>> >>>> time-nuts mailing list -- time-nuts at febo.com
>>> >>>> To unsubscribe, go to
>>> >>>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>>> >>>> and follow the instructions there.
>>> >>>>
>>> >>>
>>> >>>
>>> >>>
>>> >>>
>>> >>> ------------------------------
>>> >>>
>>> >>> Message: 7
>>> >>> Date: Fri, 01 Oct 2010 17:50:17 -0500
>>> >>> From: Brian Kirby <kilodelta4foxmike at gmail.com>
>>> >>> Subject: Re: [time-nuts] Possibly OT - Any interest in a vintage
>>> >>> HP/Dymec DY-5842 VLF receiver?
>>> >>> To: Discussion of precise time and frequency measurement
>>> >>> <time-nuts at febo.com>
>>> >>> Message-ID: <4CA665A9.1090908 at gmail.com>
>>> >>> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>>> >>>
>>> >>> You might consider contacting Dr. Ken Kuhn  --
>>> kennathakuhn at gmail.com
>>> >>>
>>> >>> check his HP museum at http://www.kennethkuhn.com/hpmuseum/
>>> >>>
>>> >>> Brian Kirby KD4FM
>>> >>>
>>> >>>
>>> >>>
>>> >>> On 10/1/2010 5:34 PM, ziggy9 wrote:
>>> >>>>
>>> >>>> Fellow time-nuts:
>>> >>>> I've got a circa 1964 DY-5842 VLF receiver. This is (was) operated
>>> in
>>> >>>> conjunction with an external time interval counter to make a
>> frequency
>>> >>>> comparison. So you would select WWVL for example, and use that as
>> your
>>> >>>> primary standard for comparison to your local standard. It's got 5
>>> > crystals
>>> >>>> in it: 16, 18, 19.8, 20, and 60 kHz (listed as GBR, NBA, NPM,
>>> WWVL,
>>> > WWVB).
>>> >>>> It works and I have the manual. The thing is, the interest in
>> something
>>> >>>> like this is bound to be a bit narrow, so I thought I'd mention it
>>> > here.
>>> >>>>
>>> >>>> So if there are any collectors, equipment museums, etc. that might
>>> be
>>> >>>> interested in this, please let me know. I'm a bit sentimental
>>> about
>>> > this
>>> >>>> thing, it's sort of a bit of history, and from what I can tell,
>>> > somewhat
>>> >>>> rare (doesnt make it worth anything though :). Since it's a bit of
>>> a
>>> >>>> curiosity, I'd like to pass it to someone that might be interested
>>> in
>>> > it
>>> >>>> rather than just tossing it. I can always provide more details to
>>> > anyone
>>> >>>> that wants them.
>>> >>>>
>>> >>>> Best regards,
>>> >>>> Paul Davis - K9MR
>>> >>>>
>>> >>>>
>>> >>>> _______________________________________________
>>> >>>> time-nuts mailing list -- time-nuts at febo.com
>>> >>>> To unsubscribe, go to
>>> > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>>> >>>> and follow the instructions there.
>>> >>>>
>>> >>>
>>> >>
>>> >>
>>> >> _______________________________________________
>>> >> time-nuts mailing list -- time-nuts at febo.com
>>> >> To unsubscribe, go to
>>> > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
>>> >> and follow the instructions there.
>>> >
>>> >
>>> >
>>> >
>>> > ------------------------------
>>> >
>>> > _______________________________________________
>>> > time-nuts mailing list
>>> > time-nuts at febo.com
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>>> >
>>> > End of time-nuts Digest, Vol 75, Issue 4
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>>>
>>>
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>
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