I had an email query from a HF Milcom monitor over the weekend asking me about the Japanese language comms on 6727.0 kHz USB. They believed it might be military in nature.
That is a very good catch and it is a Japanese military net. In fact, this net has been around 1973. It is a frequency used by the Japanese Self Defense Force (自衛隊, Jieitai), Air Traffic Control Squadron 1. This unit is located at the Ayase City, Kanagawa Prefecture and controls SDF and MSDF aircraft offshore of the islands to Hawaii and south to the equator. Shore station operators are primary YL (female) ops and use the callsign "Atsugioshanikku." Primary traffic is weather information and position reporting. And now you know the rest of the story.
While I am on the subject of the Japanese Self Defense Forces, I have been doing some extra searching around and here are some JSDF Air Defense group callsigns that I have dug up. I could use so help filling in the holes in the list below and the frequencies used by these units so feel free to contact me at the email address in the masthead.
Northern Air Defense Control Group
HEAD WORK Northern Air Defense Control Group - Misawa, Aomori Prefecture, DC 北部防空管制群 (青森県三沢ＤＣ）
KEY HOLE 18 Warning Group - Wakkanai, Hokkaido SS 第１８警戒群（北海道稚内ＳＳ）
DIVER 26 Warning Group - Nemuro, Hokkaido SS 第２６警戒群（北海道根室ＳＳ）
HARNESS 28 Warning Group - Abashiri, Hokkaido SS 第２８警戒群（北海道網走ＳＳ）
LAMINATE 29 Warning Group - Okushiri Hokkaido SS 第２９警戒群（北海道奥尻ＳＳ）
NAME PLATE 33 Warning Group - Akita Prefectural Kamo SS 第３３警戒群（秋田県加茂ＳＳ）
BACK GROUND 36 Warning Group - Erimo Hokkaido SS 第３６警戒群（北海道えりもＳＳ）
ZIP GUN 37 Warning Group - Yamada, Iwate 第３７警戒群（岩手県山田ＳＳ）
JACK KNIFE 42 Warning Group - Ominato Aomori 第４２警戒群（青森県大湊ＳＳ）
QUICK SAND 45 Warning Group - Toubetsu Hokkaido 第４５警戒群（北海道当別ＳＳ）
Central Air Defense Control Group
OFF SIDE Central Air Defense Control Group - Iruma, Saitama, DC 中部防空管制群（埼玉県入間ＤＣ）
TEA BAG 1 Group (Vigilance) (MIE笠取山SS ) 第１警戒群（三重県笠取山ＳＳ）
GOOD MAN 5 Warning Group - Kushimoto, Wakayama Prefecture 第５警戒群（和歌山県串本ＳＳ）
YARD ARM 22 Warning - Omaezaki, Shizuoka 第２２警戒群（静岡県御前崎ＳＳ）
MASCOT 23 Warning Group - Wajima, Ishikawa SS 第２３警戒群（石川県輪島ＳＳ）
CATS EYE 27 Warning - 大滝根山Fukushima 第２７警戒群（福島県大滝根山ＳＳ）
EAST WOOD 35 Warning - via Kensington Kyoto Qi SS 第３５警戒群（京都府経ケ崎ＳＳ）
FREE STONE 44 Warning - Okayama Mine棄県1000 SS 第４４警戒群（千棄県峯岡山ＳＳ）
ABLE GATE 46 Warning - Sado new渇県SS 第４６警戒群（新渇県佐渡ＳＳ）
Western Air Defense Control Group
DIALECT Western Air Defense Control Group (Kasuga, Fukuoka Prefecture, DC) 西部防空管制群（福岡県春日ＤＣ）
PIPE ORGAN 7 Group (Caution) - Shimane Prefecture Mt SS 第７警戒群（島根県高尾山ＳＳ）
I-BEAM 9 Group (Guard) - Island, Kagoshima Shimokoshiki SS 第９警戒群（鹿児島下甑島ＳＳ）
SHORT STOP 13 Warning Group - Hatakeyama Takashi Miyazaki 第１３警戒群（宮崎県高畑山ＳＳ)
UNIPED 15 Warning Group - Fukue Island, Nagasaki Prefecture, SS 第１５警戒群（長崎県福江島ＳＳ）
VENTURE 17 Warning Group - Mishima, Yamaguchi Prefecture 第１７警戒群（山口県見島ＳＳ）
RACKET 19 Warning Group - Awashima Sea Nagasaki 第１９警戒群（長崎県海粟島ＳＳ）
WATCH MAN Warning Group - Mountain Sefuri Saga SS 第４３警戒群（佐賀県背振山ＳＳ）
Southwest Air Defense Control Group
ROAD RICK Southwest Air Defense Control Group - Naha, Okinawa DC 南西防空管制群（沖縄県那覇ＤＣ）
PYRAMID FURUSHIMA 53 Warning Group - Okinawa Prefecture Government SS )第５３警戒群（沖縄県官古島ＳＳ
HARRIER 54 Warning Group - Island in Okinawa SS 第５４警戒群（沖縄県久米島ＳＳ）
READ MIT 55 Warning Group - Okinoerabu Island, Okinawa Prefecture, SS 第５５警戒群（沖縄県沖永良部島ＳＳ
ZEPPELIN 56 Warning Group - Mt Yoza Okinawa 第５６警戒群（沖縄県与座岳ＳＳ）