Radiofax: VMC Charleville, QLD/VMW Wiluna, WA (Bureau of Meteorology, Australia)

The radiofax series of posts have gone on for a while, but lately, the number of postings have become rather slim. What might not be so evident is that the monitoring efforts continue, perhaps even more intensely than at the beginning, as I’ve spent many countless hours monitoring multiple frequencies at a time across a number of receivers only to come up with negative result after negative result.

The series would have probably drawn to a close much sooner, if I had not discovered an extensive list of old frequencies which I felt needed double-checking to confirm they were off the air and if it were not for the fact my local radiofax system (VMC Charleville and VMW Wiluna) is currently unwell, sending out faxes with phase jumps in them.

I sent out an e-mail to the Bureau of Meteorology back on 22nd January 2019, which they confirmed a fault by 25th January. This was apparently escalated to the external vendor for rectification. However, the system continues to malfunction to this day. I’m not sure myself, but somehow it feels like an issue with either a clock reference or perhaps an ill-advised upgrade to systems (e.g. transferring something which used to be leased-line to VoIP perhaps). However, the size of the jumps are not the right size for standard packet buffer lengths … so I’m not sure if this hypothesis holds.

Then, one night, I had a thought. Maybe radiofax systems don’t just suddenly go off the air. Maybe they become ill, perhaps terminally, eventually leading to them falling off the air or being replaced by something entirely different. Maybe this is what happened to GYA? Maybe this is VMC/VMW telling me that I should take what I can and not wait for a recovery …

While I have covered VMC/VMW previously in the past from home, the effort was not a comprehensive attempt to collect one of every type of fax. As the station is local, it was sufficient to use Tecsun Radios Australia’s KiwiSDR, receiving VMC over 5100, 11030 and 13920kHz on just 1st March 2019 to collect all the charts. Copyright in the faxed materials belongs to the Bureau of Meteorology (Commonwealth of Australia) with the faxes reproduced for documentary purposes, to illustrate the format of the faxed materials, the type of faxed materials and as proof of their transmission, propagation and reception at the stated dates and times.

The Faxes

As all faxes were received on 1st March 2019, only the UTC times will be given for the example charts. Most charts are preceded by one minute of white-tone for tuning purposes. VMC and VMW simulcast transmission over different frequencies, following the same program. WMO start/stop tones are used for APT with relatively short length and a white image margin. Due to a malfunction, the transmitted images exhibit phase jumps. There is a preference to short-charts with only a few exceptions.

The slant correction of kiwifax.py has been modified so as to ensure the jumps “line up” and the image remains within the area instead of “slipping” towards the left progressively. As a result, the images do not look like this when the system is operating correctly. Charts are presented categorised by their type/function.

System-related Charts

The first system-related chart is actually an unlisted test chart which appears to be transmitted at 0530UTC regularly. The chart is sent sideways in landscape, with the final line cut-off.

The most important system-related charts are the schedules. It seems that the schedule had been redone on 1st May 2017, and the resulting schedule is sent seascape as two parts. Unlike the old schedule which appeared to use a font akin to Arial and had a very smooth appearance, this one now appears quite harsh looking and low-resolution. Combined with the phase jumps, it makes it a little difficult to read. The first part was received at 0015UTC.

The second part follows the same formatting and is equally as harsh on the eyes, received 0030UTC.

This is followed by the VMC/VMW Broadcast Information at 0045UTC sent portrait orientation. This one is so low resolution that it qualifies as being mostly unreadable even in the best of reception conditions – it seems that it was not uploaded properly to the system resulting in this rather “cryptic” looking fax.

The VMC/VMW Voice Broadcast Information is as traditional – this is how the schedule used to appear, at least font and quality wise. It seems this has not changed, hence retains the smooth and easy-to-read appearance, along with the dirt from when it was scanned. This example received 0315UTC.

Propagation-related Charts

Unlike all other weatherfax stations, VMC/VMW broadcast a series of faxes which issue recommendations about which frequency to use at what time. This forecast is based on the Ionospheric Prediction Service which we have, which is now part of the Space Weather Services division of the Bureau of Meteorology. All receptions of these charts were made on 11030kHz.

Received 0100UTC, the first of three pages illustrating the predicted propagation for VMC in Charleville, Queensland. Note the misspelling in the footer of the suburb Haymarket as “Haymarkwt” which has been the case ever since I remember.

The second part is sent at around 0110UTC, following the same format but omitting tuning tone prior to the chart. The chart is divided into nine hourly maps with each each inset figure covering one hour. The first and last image overlap with the previous and next page respectively. Frequencies are number-coded onto contours.

The third and final part is transmitted around 0120UTC. This is followed by another three charts following the same format which cover the same predictions but instead for VMW Wiluna in Western Australia.

The first page is received 0131UTC. It’s important that these predictions have about one week validity and are based on actual space weather inputs – not just a static guide, hence their regular transmission schedule.

The second page is received around 0141UTC.

The final, and slightly noisy, page is received at around 0151UTC. One thing to note is that VMC and VMW are operating at just 1kW emission power (as compared with some neighbours operating up to 10kW) which means that choosing the right frequency could be a lot more important to receiving usable charts.

Surface Analysis

The above surface analysis relates to the Indian Ocean area, received 0000UTC.

This surface analysis relates to the Australian area, received 0245UTC.

This surface analysis received 0400UTC relates to the South Pacific Ocean area. All three charts presented thus far are all short charts with relatively low resolution and a chunky appearance. Thick text and lines make for ease of reading even under poor signal conditions, although they do not look as attractive from an aesthetics perspective. The charts really only use black and white transmission – greyscales do not appear to feature at all.

This surface analysis from Darwin RSMC follows slightly different conventions with much finer lines and smoother higher resolution output. The chart above received at 0645UTC is the Asian area MSLP analysis.

Surface Forecast

Surface forecast products include the Australian Mean Sea Level Pressure Forecast (H+36) received 0203UTC as above. The resolution for this chart seems to be below the normal expected resolution – the logo and issue time are very difficult to read.

The four day forecast MSLP prognosis is sent as two separate charts. This first part received at 0430UTC shows the first two days – with significant headers and footers above the square inset maps.

The same format is repeated at 0445UTC for the latter two days.

A slightly different chart is the Southern Hemisphere MSLP forecast (H+48) as received 1045UTC. This is an almost square chart, sent landscape orientation focusing on the pole and appears to be the only hemispherical product in the line-up.

The Indian Ocean MSLP forecast (H+36) is received at 1245UTC, clearly identified as Bureau of Meteorology in the top left with ACCESS-Global in the top right. This chart has slightly less resolutions and lines of nearly equal thickness.

The H+48 version of the above is received at 2345UTC but follows a slightly different format with an even lower resolution image to the point it is very obviously pixelated and slightly difficult to read.

Sea Surface Temperature Analysis

The VMC/VMW system offers three sea surface temperature analysis charts which are often the ones most easily received due to their large text and contiguous black and white portions. The example above from 1130UTC is the Asian Sea Surface Temperature Analysis.

Another example is this one from 1345UTC which is the Pacific Ocean Sea Surface Temperature.

Finally, this example from 1400UTC which is the Indian Ocean Sea Surface Temperature. All analyses show similar formatting, with different aspect ratios and coverage areas.

Gradient Level Wind Analysis

Two gradient level wind analysis charts are available – the above at 0600UTC for Area A.

This is followed by one for Area B at 0623UTC. These are the only two charts that are “tall” charts sent in portrait orientation, with the remainder of the charts being mostly “short” to “square” charts.

Wind/Wave Analysis and Forecast

At 0300UTC, the Primary Swell Height and Direction (H+24) chart was received. The chart uses shading to illustrate wave height regions, covering the Australian region.

Total Wave Height and Direction (H+24) for the Australian region was received at 1930UTC (as the 0745UTC was affected severely by propagation). Note that the model for this is AUSWAVE Regional as illustrated in the top left of the chart.

 

The Southern Ocean Total Wave Height and Direction (H+24) is received at 1015UTC, with a model of AUSWAVE Global.

At 1100UTC, an H+36 version following the same format is received.

At 1315UTC, Total Wave Height and Direction (H+48) for South Pacific Ocean is received.

At 1330UTC, the version covering the Indian Ocean is received. These charts appear to have better resolution compared to the majority of the other charts, with fine line grids and small text.

Finally, Total Wave Height and Direction for Southern Ocean area at 1415UTC.

Conclusion

It’s unfortunate the local weatherfax station to me is not functioning correctly with phase jumps in the images. However, as it has not been fixed in a month, I have some fears that this may mean that something big could be on the way – maybe a change of system or maybe the decommissioning of the system, so I thought perhaps preserving the system “as is” is better than ignoring it altogether.

Most of the charts sent, with the exception of the gradient level wind analysis charts, are short charts. All charts are preceded by WMO tones, most by white-tuning tone for a minute and trailed by black tone for five seconds. The image margins are white, with a regular amount of phasing area preceding the chart. Aside from the phase jumps, it seems that the chart resolution seems to be quite poor for some charts (possibly as they may not have uploaded them at the best quality to the system).

Unlike other systems, the Australian system is special in that it simulcasts from two transmission sites across several frequencies, but transmits at a much lower power than many of our neighbours. We also offer propagation prediction charts to help decide which frequencies to use given your location and time, based on actual space weather.

I hope to see the system return to health and perhaps, to better resolution charts as well. But for now, it is preserved …

Radiofax Station Status [Updated: 3rd March 2019]

The latest update to the slant factors are as follows:

Callsign	Correction
--------------- ----------
CBM/CBV		-90.0
DDH/DDK		-12.0
GYA		+34.0
HLL2		-18.0
HSW64		-11.0
NOJ/NMC/NMF/NMG	-4.0
KVM70 		-4.0
JFX		 0.0
JJC/9VF		+3.2
JMH		 0.0
RBW41		-17.0
VCO		-24.0
VMC/VMW         +18.0 (unwell)
ZKLF		+11.0
ZSJ             +100.0

The latest update to the station status are as follows:

Station Status as at 3rd March 2019 (based on my observations)
CALL  COUNTRY           STATUS
----  ----------------- --------------------------------------------
ZSJ   South Africa      * Alive but Unreliable (Published)
JMH   Japan             - Alive and Well (Published)
???   Chukota Peninsula ? Unknown, Not Heard
BMF   Taiwan            X Confirmed OFFLINE (see above)
HLL2  South Korea       - Alive and Well (Published)
HSW64 Thailand          - Alive and Well (Published)
JJC   Japan             - Alive and Well (Published)
9VF   Singapore         - Alive and Well (See Images Following)
GYA   Persian Gulf      X Reported Inactive, Not Heard
PWZ33 Brazil            ? Unknown, Not Heard
CB?   Chile             - Alive and Well (Published)
CFH   Canada            X Reported Inactive, Not Heard
VFF   Canada            ? Seasonal, Not Heard
VFR   Canada            ? Seasonal, Not Heard
VCO   Canada            - Alive and Well (Published)
VFA   Canada            ? Seasonal, Not Heard
NOJ   USA               - Alive and Well (Published)
NMC   USA               - Alive and Well (Published)
NMG   USA               - Alive and Well (Published)
NMF   USA               - Alive and Well (Published)
VM?   Australia         * Alive but (Temporarily) Unwell (This Post)
ZKLF  New Zealand       - Alive and Well (Published)
KVM70 USA               - Alive and Well (Published)
SVJ4  Greece            - Alive and Well (Published)
RBW4? Russia            - Alive and Well (Published)
DD??  Germany           - Alive and Well (Published)
GYA   United Kingdom    - Alive and Well (Published)
JFX   Japan             - Alive and Well (Published)

Historical stations from hffax.de have been removed from the list, as after monitoring all 50-60 frequencies for services not in current schedules for 24 hours each (an intensive effort), no signals were seen. None of the additional stations taken from the WMO guide were seen to be active either and are removed from the list. Given the age of the data from 2002, there is a good chance that all of them are offline. On a suggestion from Vitor, monitoring efforts are now pointed towards XSG Shanghai, a relatively unknown station which I’m hoping to add to the list.

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I'm a bit of a nut for electronics, computing, photography, radio, satellite and other technical hobbies. Click for more about me!
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