JMH/JMH2/JMH4 Japan Meterological Agency Radio Fax

JMH/JMH2/JMH4 are a set of radiofax stations transmitting from Tokyo, Japan. They had many more transmitters formerly – hence the “gaps” in the numbering, luckily they haven’t discontinued the service altogether.

Transmissions are all made at 5kW, and all three frequencies (center) at 3622.5khz, 7795khz and 13988.5khz have been heard from Sydney, Australia. Generally, the 7795khz is the best frequency, with 13988.5khz only available for limited periods, and 3622.5khz is severely affected by noise and static.

Unfortunately, I haven’t been able to find any contact at JMA for QSL requests – so I won’t get a QSL for this one, but that’s okay. Receiving the images are most of the fun anyway! Transmissions consist of white-tone for tuning, followed by a short start tone, then regular phasing. During the image, the margin is negative (black), and end of transmission is marked by a short stop tone followed by black for about 5 seconds.

Lets start off with the “unusual” faxes. Time will be given in local time (UTC+11) for the end of the fax. All reception done on JMH2 at 7795khz.

Test Fax – 6th Feb 2013 ending 0010

test_20130206_0010

Test Fax – 7th Feb 2013 ending 0009

test_20130207_0009

Test Fax – 8th Feb 2013 ending 0009

test_20130208_0009

This is a test fax – note how over the case of several days, the propagation is completely different and the quality of the fax varies significantly! I guess it reinforces the need to be patient and persistent if you want to get a good copy!

Trouble Fax – 5th Feb 2013 ending 0403

trouble_20130205_0321

Trouble Fax – 5th Feb 2013 ending 0321 trouble_20130205_0403

Normally a rare sight – these are trouble faxes which are sent when there’s something wrong with the system. In fact, I was able to receive three of them – but I’ve put the two clearest ones up here.

Regular Faxes

Surface Analysis – 5th Feb 2013 ending 0158

surfana_20130205_0158

Sea Surface 100m Temperatures – 6th Feb 2013 ending 0135

seasurf100mtemp_20130206_0135

Unknown – Pairs of Charts 1 – 8th Feb 2013 ending 0450

pair-chart_20130208_0450

Unknown – Pairs of Charts 2 – 8th Feb 2013 ending 0521

pairchart2_20130208_0521

Unknown – Pairs of Charts 3 – 8th Feb 2013 ending 0532

pairchart3_20130208_0532

Unknown – Pairs of Charts 4 – 8th Feb 2013 ending 0543

pairchart4_20130208_0543

MTSAT Satellite Image – 6th Feb 2013 ending 0627

mtsat_20130206_0627

Mean Sea Surface Temperatures – 6th Feb 2013 ending 0315

meanseasurft_20130206_0315

Ice Conditions – 6th Feb 2013 ending 2138

icecond_20130206_2138

Unknown – Four Charts – 7th Feb 2013 ending 0608

fwp4_20130207_0608

48h Surface Prognosis – 7th Feb 2013 ending 2118

48hsurfprog_20130207_2118

24h Wave Forecast – 7th Feb 2013 ending 2259

24hwavefcst_20130207_2259

24h Wave Forecast – 7th Feb 2013 ending 0648

24hsurfprog_20130207_0648

Wave Analysis – 7th Feb 2013 ending 2328

waveanaly_20130207_2328

Unknown – 7th Feb 2013 ending 2059

unknown_20130207_2059

Unknown – 5th Feb 2013 ending 2138

unknown_20130205_2138

Which covers all of the different sorts of charts that I have seen when monitoring JMH stations.

About lui_gough

I'm a bit of a nut for electronics, computing, photography, radio, satellite and other technical hobbies. Click for more about me!
This entry was posted in Radio and tagged , . Bookmark the permalink.

Error: Comment is Missing!