Radiofax: NOJ Kodiak, Alaska (National Weather Service/NOAA, USA)

Continuing on the list of active stations I have yet to make a post about, the NOJ station in Kodiak, Alaska operated by National Weather Service/National Oceanic and Atmospheric Administration of the United States of America has been a difficult station to catch. Situated in an area where there are not many nearby receivers, transmitting at a claimed 4kW over four frequencies, the difficulties in getting any charts from the station must not be underestimated.

For one, I had to enlist the help of the nearest KiwiSDRs that could hear any signal. Despite scouring almost all of the west coast of the USA and into Canada, only two stations ever got any signal – this was NM7A (Deer Harbor, Washington), K9VD (Machias, Washington) and AI6VN (Maui, Hawaii) which is a credit to their antennas and relatively low noise floor. The other issue was QRM and lots of it – the 4298kHz frequency was very much flanked by QRM from “8FSK” signal from Japan while others did not propagate well at all. This meant that kiwifax.py would rarely ever detect a start signal and that faxes would come in with lots of noise and inversions due to relative fading between the interfering signal and the desired signal. One of the better receivers had a one-hour-per-day limit as well, to add to the challenge and one of the frequencies for the station is incorrectly listed as 12410.6kHz when it should be 12412.5kHz (which I’ve notified them about).

As a result, this post will be a collection of more “noisy” and “strange” looking charts than the pristine charts of some other posts, however, it does prove that NOJ is still active at this time. The supplied charts are not up to date and are not to be used for navigation purposes. Copyright in the chart material remains property of the transmitting agency, National Weather Service/National Oceanic and Atmospheric Administration of the United States of America. Charts are reproduced here for documentary purposes to show the transmission characteristics, formatting of the data within the charts and as proof of station activity, propagation and reception on the dates and times listed. Up-to-date charts can be downloaded from http://tgftp.nws.noaa.gov/fax/marine.shtml

Faxes

Despite multiple attempts at monitoring, I was only able to receive any recognisable charts on 19th January 2019 and on 31st January 2019 on 4298kHz. Because of the method of reception, UTC times for the charts were not recorded but have been filled in based on best estimates based on the available schedule.

Reception from 19th January 2019

This first chart appears to be a 24-hour Wind and Wave Forecast in Feet (1027UTC). The NOAA logo is somewhat visible, with the interference causing noise in dark areas and periods of colour “inversion” possibly due to competing strengths of signals as one fades in/out. There is clear evidence to show the NWS/NOAA family traits of the data-dots in the top-left image area and black margins in the image area are preserved.

The second chart is not identified clearly, but appears to be possibly a 48-hour Surface Forecast (based on some very fine guesswork, 1037UTC). It seems the repetitive patterns of the interfering signal cause strange banding to appear in certain areas near the phasing area. Like other NWS/NOAA stations, short charts seem to be the preference.

The first tall chart appears to be a 5-Day Sea Ice Forecast from the NWS Alaska Sea Ice Program (1057UTC)  with the header text barely readable.

This mess of a chart appears to be a satellite image (1117UTC) as it has very few sharp and distinct features, but contains greyscale.

This could be the 48-hour wave period/swell direction chart (1128UTC) at a guess …

… and this could be the 48-hour 500MB forecast (1138UTC) based on the thicker text in the top box.

This one is definitely the Sea Surface Temperature Analysis (1148UTC).

Reception from 31st January 2019

We begin reception on 31st with what could also be another satellite image.

The chart that follows sure looks like a 48-hour wave period/swell direction chart (1128UTC).

This appears to be the expected 48-hour 500MB forecast (1138UTC).

That is followed by the Sea Surface Temperature Analysis (1148UTC), this time with an unreadable header but readable legend.

As the images were not necessarily processed in order – this is clearly a 48-hour Surface Forecast but reception time is uncertain (0437/1037/1637/2203UTC?).

This is a 96-hour Surface Forecast (0447/1647/2348UTC?).

This is also readably a Sea State Analysis, although none of these charts are truly readable. Time is either 0456/1656UTC.

Another satellite image, it seems … (0506/1706/1117/2307UTC?).

Hard to tell what this is? A 48-hour surface forecast?

Through the noise and inversion, the rather valuable schedule was able to be received but only with the bold/large text readable (1727UTC). Note the frequencies as listed on the schedule did not match the NWS/NOAA radiofax schedules document that I had (7th September 2018 edition).

No idea what this chart and the following chart are …

… but both charts are completely inverted.

This 48-hour surface forecast is probably the “clearest” reception of the lot to the point it seems partially readable.

The 48-hour Wind & Wave Forecast is also readable but faded. It seems the interference from the 8FSK station causes a lot of difficulty for reception.

Conclusion

While I would have rather had good pristine charts to show, having any charts at all is still a useful indication of the status of the station which is still active. Owing to the number of charts received that are “specific” to this station, there is no doubt that the signal emanates from NOJ. The strange quality of inversions caused by competing interference is quite unique and something experienced by other DXers looking to receive NOJ’s transmissions. However, for the most part, charts follow similar convention to other NWS/NOAA family stations with clear logo/text identification and a preference for short charts with data-dots and a black image margin.

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