Fwd: [time-nuts] With CHU going off the air WBCQ shortwave radio may use one of its transmitters as a time station.

[David G. McGaw]

Here is an interesting proposal.

73,

David N1HAC

-------- Forwarded Message --------

Subject:	[time-nuts] With CHU going off the air WBCQ shortwave radio may use one of its transmitters as a time station.
Date:	Wed, 3 Jun 2026 20:17:54 -0400
From:	WBCQ Radio via time-nuts <time...@lists.febo.com>
Reply-To:	Discussion of precise time and frequency measurement <time...@lists.febo.com>
To:	time...@lists.febo.com
CC:	WBCQ Radio <wbcq...@gmail.com>

Hi Time folk,

We are WBCQ radio international broadcast station located in northern
Maine.

We are licensed to broadcast on several shortwave frequencies, check
wbcq.com for more info.

We just heard of the impending shutdown of CHU in Canada. Sad news.

We have an unused transmitter on 3265khz.

What equipment would we require to turn it into a "time station" ??

Thanks,
Allan Weiner
WBCQ Radio
wbcq.com
207-889-0039
_______________________________________________
time-nuts mailing list -- time...@lists.febo.com
To unsubscribe send an email to time-nu...@lists.febo.com

[Ethan Miller K8GU]

Dave,

That is indeed an interesting proposal!  About 15 years ago, I was involved with an experiment that looked at propagation and signal characteristics of several SWBC stations in eastern North America and WBCQ was not especially stable at the time.  A lot can change, I suppose.

73,

--Ethan, K8GU.

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[Phil Karn]

I proposed something like this during the Monday night engineering net. My thinking is not to transmit time signals, but to simply give them the hardware they need to transmit a highly stable carrier on any of their frequencies, not just an idle one. Let the guy providing the sidebands foot the power bill.

Phil

To view this discussion visit https://groups.google.com/d/msgid/hamsci/CAFkosZJBSiOZMLzN%3D_vRz%2BOwbtUdXOR%2BfN3fifCLcHNw5F71-A%40mail.gmail.com.

[Dave Doler]

Allan might want to monitor GC Surplus to see if any CHU assets go to auction.

https://gcsurplus.ca/mn-eng.cfm

[Michael St. Angelo]

Does anyone remember that during the Cold War powerhouse AM stations such as WABC in New York transmitted narrow frequency shift keying on their Am signal for military purposes. Does anyone know of a description of that system?

Thanks Mike N2MS

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[googl...@cox.net]

David,

 

This is an interesting offer. Has anyone within HamSci or Time-Nuts reached out to Allan? Just want to make sure no one is stepping on anyone else’s toes…

 

We really don’t need a “time station” in the classical sense; we need a high-stability carrier signal. Perhaps a GPS disciplined oscillator with a rubidium standard could be used to replace their existing frequency reference source and support ALL their shortwave transmitters.

 

73,

 

Mark Braunstein  WA4KFZ

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[Michael St. Angelo]

I proposed that WBCQ transmitters use accurate time bases. Someone from  HamSci should socialize their requirements via  Time-Nuts.

Good Luck,

Mike N2MS

To view this discussion visit https://groups.google.com/d/msgid/hamsci/00ca01dcf458%2441a2a5f0%24c4e7f1d0%24%40cox.net.

[John Ackermann N8UR]

HI Mike --

There's a group of time-nuts and HamSci folks who are coming together to
do just that.

73,
John
----

On 6/5/26 20:44, Michael St. Angelo wrote:
> I proposed that WBCQ transmitters use accurate time bases. Someone from
> HamSci should socialize their requirements via  Time-Nuts.
>
> Good Luck,
>
> Mike N2MS
>
> On Thu, Jun 4, 2026 at 3:28 PM <googl...@cox.net

> <mailto:googl...@cox.net>> wrote:
>
> David,____
>
> __ __

>
> This is an interesting offer. Has anyone within HamSci or Time-Nuts
> reached out to Allan? Just want to make sure no one is stepping on

> anyone else’s toes…____
>
> __ __

>
> We really don’t need a “time station” in the classical sense; we
> need a high-stability carrier signal. Perhaps a GPS disciplined
> oscillator with a rubidium standard could be used to replace their
> existing frequency reference source and support ALL their shortwave

> transmitters. ____
>
> __ __
>
> 73,____
>
> __ __
>
> Mark Braunstein  WA4KFZ____
>
> __ __
>
> __ __
>
> *From:*ham...@googlegroups.com <mailto:ham...@googlegroups.com>
> <ham...@googlegroups.com <mailto:ham...@googlegroups.com>> *On
> Behalf Of *David G. McGaw
> *Sent:* Wednesday, June 3, 2026 21:50
> *To:* ham...@googlegroups.com <mailto:ham...@googlegroups.com>
> *Subject:* [HamSCI] Fwd: [time-nuts] With CHU going off the air WBCQ
> shortwave radio may use one of its transmitters as a time station.____
>
> __ __

>
> Here is an interesting proposal.
>
> 73,
>

> David N1HAC____
>
>
> -------- Forwarded Message -------- ____
>
> *Subject: ____*

>
>
>
> [time-nuts] With CHU going off the air WBCQ shortwave radio may use

> one of its transmitters as a time station.____
>
> *Date: ____*
>
>
>
> Wed, 3 Jun 2026 20:17:54 -0400____
>
> *From: ____*
>
>
>
> WBCQ Radio via time-nuts <time...@lists.febo.com> <mailto:time-
> nu...@lists.febo.com>____
>
> *Reply-To: ____*
>
>
>
> Discussion of precise time and frequency measurement <time-
> nu...@lists.febo.com> <mailto:time...@lists.febo.com>____
>
> *To: ____*
>
>
>
> time...@lists.febo.com <mailto:time...@lists.febo.com>____
>
> *CC: ____*
>
>
>
> WBCQ Radio <wbcq...@gmail.com> <mailto:wbcq...@gmail.com>____

>
>
>
> Hi Time folk,
>
> We are WBCQ radio international broadcast station located in northern
> Maine.
>
> We are licensed to broadcast on several shortwave frequencies, check

> wbcq.com <http://wbcq.com> for more info.

>
> We just heard of the impending shutdown of CHU in Canada. Sad news.
>
> We have an unused transmitter on 3265khz.
>
> What equipment would we require to turn it into a "time station" ??
>
> Thanks,
> Allan Weiner
> WBCQ Radio

> wbcq.com <http://wbcq.com>
> 207-889-0039
> _______________________________________________
> time-nuts mailing list -- time...@lists.febo.com <mailto:time-
> nu...@lists.febo.com>

> To unsubscribe send an email to time-nu...@lists.febo.com

> <mailto:time-nu...@lists.febo.com>____

>
> --
> Please follow the HamSCI Community Participation Guidelines at

> http://hamsci.org/hamsci-community-participation-guidelines <http://
> hamsci.org/hamsci-community-participation-guidelines>.

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> hamsci/fad71069-bbff-4f2a-b09c-db7db7bf6623%40dartmouth.edu

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> db7db7bf6623%40dartmouth.edu?utm_medium=email&utm_source=footer>.____

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[googl...@cox.net]

John,

Do we know if their transmitters operate from a master reference source (such as 10MHz) or are the oscillators using old-school ovenized crystals cut for each specific transmit frequency?

73,

Mark Braunstein WA4KFZ

Please follow the HamSCI Community Participation Guidelines at http://hamsci.org/hamsci-community-participation-guidelines.

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[Steve Cerwin]

There are two transmission features that facilitate bottom side ionospheric sounding. The one most talked about is extreme carrier frequency accuracy and stability to facilitate Doppler measurements. Doppler shift gives us the rate of path length change. The second is accurate and recognizable per-second time markers. The time difference between the1-pps output from a receive station GPSDO and the start of the time marker gives Time of Flight (TOF) between the two stations. TOF and a propagation model can provide insights to propagation mode (e.g., nature and number of hops) and actual refractive layer height. 

I did this with WWV's per-second timing ticks in 2019 over a 4-hour morning session from South Texas. I was able to discern TOF's that showed correlation to multiple hops from F2 that agreed extremely well with PHaRLAP and PropLab PRO predictions for that day. If another broadcast station is to take up the slack as a time and frequency station post-CHU, I vote for both carrier accuracy/stability and accurate/recognizable per-second markers.

Using WWV's per-second timing ticks was a bit tricky because they consisted of exactly 5-cycles of a 1kHz sine wave. The difficulties included recognizing the actual start of the pulse and multipath interference when multiple propagation modes occurred simultaneously. For example, the difference in TOF between 1, 2, and 3 hops was less than the 5 ms pulse width. If more than one mode was present, they came down on top of each other, superimposing to stretch out the length and number of cycles in the received waveform. I wound up using the start of the waveform to measure the TOF of the earliest arrival and the end of the waveform to measure the last. I say this only to stimulate thinking on a better per-second marker. Desirable attributes are the ability to facilitate TOF measurements and ability to separate multiple overlapping time-displaced returns.

Enabling both Doppler measurements and TOF measurements with the ability to discern overlapping multipath contributions could give a much better picture of the ionosphere than Doppler alone.

73, Steve WA5FRF

---

From: 'John Ackermann N8UR' via HamSCI <ham...@googlegroups.com>

Sent: Friday, June 5, 2026 7:10 PM
To: ham...@googlegroups.com <ham...@googlegroups.com>
Subject: Re: [HamSCI] Fwd: [time-nuts] With CHU going off the air WBCQ shortwave radio may use one of its transmitters as a time station.

 

Please follow the HamSCI Community Participation Guidelines at http://hamsci.org/hamsci-community-participation-guidelines.

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[googl...@cox.net]

Steve,

 

Thank you for your excellent comments. You’re right; I didn’t address the time tick part of the “time station” broadcasts from WWV and CHU.

 

I agree that we need a better way to address the per-second timing indication. WWV transmits a 100Hz subcarrier that contains a BCD time code transmitted at a rate of 1 bit per second. From what I understand, this was done to enable digital clocks to decode the BCD time information and update their displays accordingly without disrupting the station voice announcements.

https://www.nist.gov/pml/time-and-frequency-division/time-distribution/radio-station-wwv/wwv-and-wwvh-digital-time-code

 

Perhaps a subcarrier could be added to the shortwave broadcasts without disrupting the audio content. Would a PN correlation sequence be viable (at a low chip rate) to create a discernable time tick indication?

 

Some back of the envelope math:

 

100 chips per second

32 chips per symbol

Symbol duration: 0.32 seconds (or 3.125 correlations per second)

Processing gain for a 32-chip sequence: 15dB.

 

The nice thing about this offer from WBCQ is that the scientific community essentially has a “greenfield” opportunity to develop waveforms and transmissions tailored for ionospheric research. There would no longer be a need to work around the limitations of systems designed with a different use case.

 

73,

 

Mark Braunstein  WA4KFZ

To view this discussion visit https://groups.google.com/d/msgid/hamsci/BY5PR10MB4370429AF2C838DE22FF0C7ADC1E2%40BY5PR10MB4370.namprd10.prod.outlook.com.

[Steve Cerwin]

Hi Mark,

Thanks for your response. In conventional radar, range resolution and bandwidth are linked. More bandwidth gives finer resolution. So, first impression is that a low bandwidth subaudible (<200 Hz) time sequence would not have enough range resolution. Maybe a clever low bandwidth, subaudible code sequence can accomplish for ranging what extended transmission time and error correction does for weak signal work (e.g., FT-8, WSPR, JT-65 etc.). I am not familiar with that technology but it is an intriguing idea.

During the eclipse activities beginning in 2024, I worked with other HamSCI volunteers to develop and acquire data sets transmitting waveforms sensitive to multipath interference - e.g., that could reveal the Time Difference of Arrival (TDOA) of multipath modes between two amateur radio stations. This type of data can yield much the same information a Time-of-Flight measurement gives but without any absolute time references. A main thrust of the project was to open participation to the general ham community and therefore used ordinary unmodified ham SSB transceivers with nothing more than an audio interface to a computer. Our chirps, pulses, PN sequences, and BPSK modulated tones used every bit of the available 3 kHz audio bandwidth. There would be no hiding these waveforms under other programming. In this discussion, presumably the transmitter can have a frequency and time disciplined infrastructure, so more sophisticated waveforms are both possible and desired.

The TDOA exercise did well for what it was. If you are interested, we just published a paper on it:

Cerwin SA, McMahan JT, Papadopoulos AS, Piccini GN, Frissell NA, Collins KV, Montare A, Bilberry P, Blackshear S and Themens DR (2026) HamSCI HF multipath propagation mode analysis using amateur radios and audio waveforms sensitive to time difference of arrival. Front. Astron. Space Sci. 13:1723511. doi: 10.3389/fspas.2026.1723511

73, Steve WA5FRF

---

From: ham...@googlegroups.com <ham...@googlegroups.com> on behalf of googl...@cox.net <googl...@cox.net>
Sent: Saturday, June 6, 2026 11:57 AM
To: ham...@googlegroups.com <ham...@googlegroups.com>
Subject: RE: [HamSCI] Fwd: [time-nuts] With CHU going off the air WBCQ shortwave radio may use one of its transmitters as a time station.

 

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[Mark Braunstein]

Steve,

For the PN sequence, I wasn't envisioning a "ranging code" arrangement. Instead, I was thinking a correlation peak could be produced once a second (essentially a 1pps signal) much like the WWV "tick" transmitted once per second. If the transmitter's carrier is sufficiently stabilized (presumably by a GPS disciplined rubidium oscillator), the same reference could be used to precisely generate the chips sent out at whatever low chip rate is used. At least that way, we'd know precisely when the PN code "left the transmitter." On the receive side, a GPS disciplined oscillator (Bodnar, etc.) would be able to clock the receive correlator at a precise rate.  The PN sequence would then be detected (correlated), and the peak compared with the 1pps output of the GPS receiver system. A correlation peak SNR of 15dB would just ensure that the peak was readily detectible over the noise. GPS-referenced time is within 10ns across the entire constellation. 

The idea of using the low chip rate code is that it could be offset in the audio passband as a subcarrier and not interfere with the audio of the broadcasted program (music, voice, etc.). 

The HamSci announcement on WWV (8 minutes after the hour) contained many waveforms designed to evaluate the audio passband of the transmitter. I assume someone has evaluated the transmitter's characteristics from these waveforms, but I'm not aware of any published results. The most important characteristics would be the absolute group delay through the entire transmitter chain and the variation in group delay over time due to temperature variations in the transmitter hardware.

73,

Mark Braunstein WA4KFZ

[Rich]

Hello Steve,

 

Thank you for your email and including your (and others) recent 2026 publication detailing the TDOA exercise.

 

I initially “participated” in the HamSCI Sunrise Festival in 2022 when I first learned about the WWV Modulation Project.

 

I think it is a great resource to have this custom audio modulation waveform still being transmitted by WWV (and WWVH) and available to use for ongoing HF propagation studies. I often continue to receive and record the WWV/WWVH transmissions here in California.

 

I have been looking (hoping) for an overall publication regarding a detailed description and the analysis of TDOA using this modulation waveform. I know there have been some results presented at various workshops and conferences, however, this paper will provide a good reference and more complete understanding of both the methodology and results for me.  I have been working (on and off) on MATLAB programs to process the received I/Q data files I am currently recording (using an RFSpace SDRIQ receiver) and the reference paper will provide additional insight.

 

73,

 

Rich Belansky, KG6UDD

To view this discussion visit https://groups.google.com/d/msgid/hamsci/BY5PR10MB43700B4E0FF17D8EFC287F69DC1F2%40BY5PR10MB4370.namprd10.prod.outlook.com.

[Steve Cerwin]

Thanks Rich. I think the paper will answer most of your questions. If not, feel free to reach out to me. 

Steve

Sent from my iPhone

On Jun 8, 2026, at 6:36 PM, 'Rich' via HamSCI <ham...@googlegroups.com> wrote:



To view this discussion visit https://groups.google.com/d/msgid/hamsci/009401dcf79f%249b50b250%24d1f216f0%24%40att.net.

[Christopher Stubbs]

Motivated by the recent discussion about monitoring AM radio stations, I did a quick test of looking at the phase stability of 1060 KYM. The path is from Philadelphia to Boston. The receiver is a GPS-locked KIWI2, detuned from the carrier by 2 kHz at the receiver. Phase shifts in the carrier show up as equivalent phase shifts in the 2 kHz IF. The left panel has a few estimators for phase stability, and shows RMS phase noise in radians. The lowest curve corrects for slow Doppler. The right hand panel shows the power spectrum of the source. Horizontal axis is Hz. As long one works within +-50 Hz, the AM modulation is out of that band. 

I think at this point most AM stations in the US have well-disciplined oscillators, but even if not the observed phase variations would set a lower bound on ionospheric path variations. As mentioned earlier on this thread, using GPS-locked KIWI stations close to the emitter would enable differential measurements. 

Best to all, 

Chris (AB1WN). 

Christopher Stubbs
Professor of Physics and of Astronomy
stu...@g.harvard.edu

On Mon, Jun 08, 2026 at 7:36 PM, Rich <phys...@att.net> wrote:

Hello Steve,

 

Thank you for your email and including your (and others) recent 2026 publication detailing the TDOA exercise.

 

I initially “participated” in the HamSCI Sunrise Festival in 2022 when I first learned about the WWV Modulation Project.

 

I think it is a great resource to have this custom audio modulation waveform still being transmitted by WWV (and WWVH) and available to use for ongoing HF propagation studies. I often continue to receive and record the WWV/WWVH transmissions here in California.

 

I have been looking (hoping) for an overall publication regarding a detailed description and the analysis of TDOA using this modulation waveform. I know there have been some results presented at various workshops and conferences, however, this paper will provide a good reference and more complete understanding of both the methodology and results for me.  I have been working (on and off) on MATLAB programs to process the received I/Q data files I am currently recording (using an RFSpace SDRIQ receiver) and the reference paper will provide additional insight.

 

73,

 

Rich Belansky, KG6UDD

 

From: hamsci@googlegroups.com <hamsci@googlegroups.com> On Behalf Of Steve Cerwin
Sent: Sunday, June 7, 2026 2:13 PM
To: hamsci@googlegroups.com
Subject: Re: [HamSCI] Fwd: [time-nuts] With CHU going off the air WBCQ shortwave radio may use one of its transmitters as a time station.

 

Hi Mark,

Thanks for your response. In conventional radar, range resolution and bandwidth are linked. More bandwidth gives finer resolution. So, first impression is that a low bandwidth subaudible (<200 Hz) time sequence would not have enough range resolution. Maybe a clever low bandwidth, subaudible code sequence can accomplish for ranging what extended transmission time and error correction does for weak signal work (e.g., FT-8, WSPR, JT-65 etc.). I am not familiar with that technology but it is an intriguing idea.

 

During the eclipse activities beginning in 2024, I worked with other HamSCI volunteers to develop and acquire data sets transmitting waveforms sensitive to multipath interference - e.g., that could reveal the Time Difference of Arrival (TDOA) of multipath modes between two amateur radio stations. This type of data can yield much the same information a Time-of-Flight measurement gives but without any absolute time references. A main thrust of the project was to open participation to the general ham community and therefore used ordinary unmodified ham SSB transceivers with nothing more than an audio interface to a computer. Our chirps, pulses, PN sequences, and BPSK modulated tones used every bit of the available 3 kHz audio bandwidth. There would be no hiding these waveforms under other programming. In this discussion, presumably the transmitter can have a frequency and time disciplined infrastructure, so more sophisticated waveforms are both possible and desired.

 

The TDOA exercise did well for what it was. If you are interested, we just published a paper on it:

 

Cerwin SA, McMahan JT, Papadopoulos AS, Piccini GN, Frissell NA, Collins KV, Montare A, Bilberry P, Blackshear S and Themens DR (2026) HamSCI HF multipath propagation mode analysis using amateur radios and audio waveforms sensitive to time difference of arrival. Front. Astron. Space Sci. 13:1723511. doi: 10.3389/fspas.2026.1723511

 

73, Steve WA5FRF

 

 

 

---

From: 'John Ackermann N8UR' via HamSCI <hamsci@googlegroups.com>
Sent: Friday, June 5, 2026 7:10 PM
To: hamsci@googlegroups.com <hamsci@googlegroups.com>
Subject: Re: [HamSCI] Fwd: [time-nuts] With CHU going off the air WBCQ shortwave radio may use one of its transmitters as a time station.

 

HI Mike --

There's a group of time-nuts and HamSci folks who are coming together to
do just that.

73,
John
----

On 6/5/26 20:44, Michael St. Angelo wrote:
> I proposed that WBCQ transmitters use accurate time bases. Someone from
> HamSci should socialize their requirements via  Time-Nuts.
>
> Good Luck,
>
> Mike N2MS
>

> On Thu, Jun 4, 2026 at 3:28

 PM <google14345@cox.net

> <mailto:google14345@cox.net>> wrote:
>
>     David,____
>
>     __ __
>
>     This is an interesting offer. Has anyone within HamSci or Time-Nuts
>     reached out to Allan? Just want to make sure no one is stepping on
>     anyone else’s toes…____
>
>     __ __
>
>     We really don’t need a “time station” in the classical sense; we
>     need a high-stability carrier signal. Perhaps a GPS disciplined
>     oscillator with a rubidium standard could be used to replace their
>     existing frequency reference source and support ALL their shortwave
>     transmitters. ____
>
>     __ __
>
>     73,____
>
>     __ __
>
>     Mark Braunstein  WA4KFZ____
>
>     __ __
>
>     __ __
>

>     *From:*hamsci@googlegroups.com <mailto:hamsci@googlegroups.com>
>     <hamsci@googlegroups.com <mailto:hamsci@googlegroups.com>> *On

>     Behalf Of *David G. McGaw
>     *Sent:* Wednesday, June 3, 2026 21:50

>     *To:* hamsci@googlegroups.com <mailto:hamsci@googlegroups.com>

>     *Subject:* [HamSCI] Fwd: [time-nuts] With CHU going off the air WBCQ
>     shortwave radio may use one of its transmitters as a time station.____
>
>     __ __
>
>     Here is an interesting proposal.
>
>     73,
>
>     David N1HAC____
>
>
>     -------- Forwarded Message -------- ____
>
>     *Subject: ____*
>
>       
>
>     [time-nuts] With CHU going off the air WBCQ shortwave radio may use
>     one of its transmitters as a time station.____
>
>     *Date: ____*
>
>       
>
>     Wed, 3 Jun 2026 20:17:54 -0400____
>
>     *From: ____*
>
>       
>

>     WBCQ Radio via time-nuts <time-nuts@lists.febo.com> <mailto:time-
>     nuts@lists.febo.com>____

>
>     *Reply-To: ____*
>
>       
>
>     Discussion of precise time and frequency measurement <time-

>     nuts@lists.febo.com> <mailto:time-nuts@lists.febo.com>____
>
>     *To: ____*
>
>       
>
>     time-nuts@lists.febo.com <mailto:time-nuts@lists.febo.com>____
>
>     *CC: ____*
>
>       
>
>     WBCQ Radio <wbcq7415@gmail.com> <mailto:wbcq7415@gmail.com>____

>
>
>
>     Hi Time folk,
>
>     We are WBCQ radio international broadcast station located in northern
>     Maine.
>
>     We are licensed to broadcast on several shortwave frequencies, check
>     wbcq.com <http://wbcq.com> for more info.
>
>     We just heard of the impending shutdown of CHU in Canada. Sad news.
>
>     We have an unused transmitter on 3265khz.
>
>     What equipment would we require to turn it into a "time station" ??
>
>     Thanks,
>     Allan Weiner
>     WBCQ Radio
>     wbcq.com <http://wbcq.com>
>     207-889-0039
>     _______________________________________________

>     time-nuts mailing list -- time-nuts@lists.febo.com <mailto:time-
>     nuts@lists.febo.com>
>     To unsubscribe send an email to time-nuts-leave@lists.febo.com
>     <mailto:time-nuts-leave@lists.febo.com>____

>
>     --
>     Please follow the HamSCI Community Participation Guidelines at
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[Michael St. Angelo]

Has anyone monitored the accuracy and stability or or used them for ionospheric studies the WBCQ transmitters? This would provide a baseline before Allam decides to proceed with providing a time source.

Mike N2MS

PM <googl...@cox.net

>     *From:*ham...@googlegroups.com <mailto:ham...@googlegroups.com>
>     <ham...@googlegroups.com <mailto:ham...@googlegroups.com>> *On

>     Behalf Of *David G. McGaw
>     *Sent:* Wednesday, June 3, 2026 21:50

>     *To:* ham...@googlegroups.com <mailto:ham...@googlegroups.com>

>     *Subject:* [HamSCI] Fwd: [time-nuts] With CHU going off the air WBCQ
>     shortwave radio may use one of its transmitters as a time station.____
>
>     __ __
>
>     Here is an interesting proposal.
>
>     73,
>
>     David N1HAC____
>
>
>     -------- Forwarded Message -------- ____
>
>     *Subject: ____*
>
>       
>
>     [time-nuts] With CHU going off the air WBCQ shortwave radio may use
>     one of its transmitters as a time station.____
>
>     *Date: ____*
>
>       
>
>     Wed, 3 Jun 2026 20:17:54 -0400____
>
>     *From: ____*
>
>       
>

>     WBCQ Radio via time-nuts <time...@lists.febo.com> <mailto:time-
>     nu...@lists.febo.com>____

>
>     *Reply-To: ____*
>
>       
>
>     Discussion of precise time and frequency measurement <time-

>     nu...@lists.febo.com> <mailto:time...@lists.febo.com>____
>
>     *To: ____*
>
>       
>

>     time...@lists.febo.com <mailto:time...@lists.febo.com>____
>
>     *CC: ____*
>
>       
>
>     WBCQ Radio <wbcq...@gmail.com> <mailto:wbcq...@gmail.com>____

>
>
>
>     Hi Time folk,
>
>     We are WBCQ radio international broadcast station located in northern
>     Maine.
>
>     We are licensed to broadcast on several shortwave frequencies, check
>     wbcq.com <http://wbcq.com> for more info.
>
>     We just heard of the impending shutdown of CHU in Canada. Sad news.
>
>     We have an unused transmitter on 3265khz.
>
>     What equipment would we require to turn it into a "time station" ??
>
>     Thanks,
>     Allan Weiner
>     WBCQ Radio
>     wbcq.com <http://wbcq.com>
>     207-889-0039
>     _______________________________________________

>     time-nuts mailing list -- time...@lists.febo.com <mailto:time-
>     nu...@lists.febo.com>
>     To unsubscribe send an email to time-nu...@lists.febo.com
>     <mailto:time-nu...@lists.febo.com>____

>
>     --
>     Please follow the HamSCI Community Participation Guidelines at
>     http://hamsci.org/hamsci-community-participation-guidelines <[http://%0b]http://
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[Scott Robson]

This is pretty neat. I understand the Kiwi is GPS disciplined, so I expect its LO to be very good, but could phase noise be introduced via sampling of the audio-level signal (2 kHz)? It's an honest, naive question. I have wondered, from time to time, how the Kiwis actually sample audio, more from a frequency accuracy perspective, but I guess now, phase noise too.

Scott (K6AUS)

On Wed, Jun 10, 2026 at 8:15 AM 'Christopher Stubbs' via HamSCI <ham...@googlegroups.com> wrote:

PM <googl...@cox.net

>     *From:*ham...@googlegroups.com <mailto:ham...@googlegroups.com>
>     <ham...@googlegroups.com <mailto:ham...@googlegroups.com>> *On

>     Behalf Of *David G. McGaw
>     *Sent:* Wednesday, June 3, 2026 21:50

>     *To:* ham...@googlegroups.com <mailto:ham...@googlegroups.com>

>     *Subject:* [HamSCI] Fwd: [time-nuts] With CHU going off the air WBCQ
>     shortwave radio may use one of its transmitters as a time station.____
>
>     __ __
>
>     Here is an interesting proposal.
>
>     73,
>
>     David N1HAC____
>
>
>     -------- Forwarded Message -------- ____
>
>     *Subject: ____*
>
>       
>
>     [time-nuts] With CHU going off the air WBCQ shortwave radio may use
>     one of its transmitters as a time station.____
>
>     *Date: ____*
>
>       
>
>     Wed, 3 Jun 2026 20:17:54 -0400____
>
>     *From: ____*
>
>       
>

>     WBCQ Radio via time-nuts <time...@lists.febo.com> <mailto:time-
>     nu...@lists.febo.com>____

>
>     *Reply-To: ____*
>
>       
>
>     Discussion of precise time and frequency measurement <time-

>     nu...@lists.febo.com> <mailto:time...@lists.febo.com>____
>
>     *To: ____*
>
>       
>

>     time...@lists.febo.com <mailto:time...@lists.febo.com>____
>
>     *CC: ____*
>
>       
>
>     WBCQ Radio <wbcq...@gmail.com> <mailto:wbcq...@gmail.com>____

>
>
>
>     Hi Time folk,
>
>     We are WBCQ radio international broadcast station located in northern
>     Maine.
>
>     We are licensed to broadcast on several shortwave frequencies, check
>     wbcq.com <http://wbcq.com> for more info.
>
>     We just heard of the impending shutdown of CHU in Canada. Sad news.
>
>     We have an unused transmitter on 3265khz.
>
>     What equipment would we require to turn it into a "time station" ??
>
>     Thanks,
>     Allan Weiner
>     WBCQ Radio
>     wbcq.com <http://wbcq.com>
>     207-889-0039
>     _______________________________________________

>     time-nuts mailing list -- time...@lists.febo.com <mailto:time-
>     nu...@lists.febo.com>
>     To unsubscribe send an email to time-nu...@lists.febo.com
>     <mailto:time-nu...@lists.febo.com>____

>
>     --
>     Please follow the HamSCI Community Participation Guidelines at
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Scott A. Robson

[David G. McGaw]

Most AM broadcast stations today do NOT have well-disciplined carriers.  Here at Dartmouth, we have had an on-going experiment measuring the Doppler shifts on a number of stations (we have reported on it several times at the HamSCI workshops).  We are GPS locked, but they are not.  We have to use a ground-wave reference to subtract the variations.

73,

David N1HAC

On 6/11/26 9:07 AM, Scott Robson wrote:

You don't often get email from scott.anth...@gmail.com. Learn why this is important

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