JS2SB, continued a third time

Original: Ryota / JJ1WTL — 521403607 · Original Japanese HTML

Published: 2026-08-23T23:37:00+09:00

English translation of the archived article text. The author’s first-person observations, uncertainty and later additions are preserved; this is not the research summary. Image contents are preserved as images, not silently incorporated into the translated prose.

Hello to fans of experimental HF digital fixed stations throughout Japan.

There seem to have been developments at the station in the title, beside Tokyo Bay Kannon. Let's visit again.

To Sanukimachi

Sunday, August 23.

Tamachi 4:52 → Tokyo 5:00 / 5:21 → Kisarazu 6:45 / 6:51 → Sanukimachi 7:24.

A Shinkansen maintenance vehicle marked MO-8570, returning toward Oi, to the right of the photograph.

Tamachi.

Tokyo.

Kisarazu. Three minutes late, partly because of slow running after an earthquake. Jump aboard.

Stopped at Onuki. It can be seen from here, but today the haze prevents it.

Arrived at Sanukimachi. Walking from here.

Passing the EM Futtsu Kokubo station.

Passing Futtsu television relay station.

JS2SB site

Arrived.

Overall view

Its present appearance. Expanded.

For comparison, previously it was two ten-element arrays stacked on each of two towers (photographed November 9, 2024):

(1) The two original towers:

Their stacks have increased from two levels to three.

(2) Three self-supporting towers have been added:

• West, rear left.

• East, rear right.

• East, lower front right.

With Kannon.

Individual towers

Original west tower.

Top: 12 elements; middle: 10; bottom: 10.

Self-supporting west tower. Twelve elements. US-bound.

Original east tower.

Top: 12 elements; middle: 10; bottom: 10.

It carries a microwave/millimetre-wave antenna aimed at Mother Farm; the counterpart appears below.

Lower eastern self-supporting tower. Ten elements.

Upper eastern self-supporting tower. Twelve elements.

US-bound. A horizontal stack paired with the western self-supporting tower?

Checking bearings

Every one comes out southwest–northeast.

Original west tower.

Self-supporting west tower. Twelve elements.

Probably US-bound.

Original east tower.

Lower eastern self-supporting tower. Ten elements.

Upper eastern self-supporting tower. Twelve elements.

US-bound.

Comparing them back-to-back, it is slightly counterclockwise from being exactly opposite.

A twelve-element array lying on the ground.

Will it replace the array on the lower eastern self-supporting tower, the only self-supporting one with ten elements?

(Did I come to look too early…?)

From Tokyo Bay Kannon

Paying ¥300 admission to the log-periodics the statue, I climb up.

From the very top—Kannon's head—you can look down like this.

JS2SB is on the rise in the centre background. North is left, south is right.

The site.

The site with another camera.

The twelve-element array on the ground is probably easier to make out from here.

Is the log-periodic on the lower eastern tower, far right, scheduled to change from ten elements to twelve?

To Mount Kanozan

Since I have come this far, let's stop there too.

Now for microwave-route exploration.

JOSADA TELECOM's northward extension to Inzai has appeared in the licence information.

My desk research suggests:

‘An antenna toward Inzai—NTT Funaho—should have been added to JOSADA TELECOM's tower on Mount Kanozan.’

That is the expectation.

Let's verify it.

Sanukimachi Station 10:00 → Jinyaji Temple 10:28.

Leaving Sanukimachi Station.

Arriving at Jinyaji Temple.

Looking back…

JOSADA TELECOM Kazusa Resort station

There you are.

The beam pointing diagonally forward-left is the new Inzai counterpart.

The one pointing diagonally forward-right is the existing Ariake link.

The essential part.

The larger antenna toward Inzai.

Compare the Inzai/NTT Funaho end:

The smaller antenna toward Inzai.

Compare the Inzai/NTT Funaho end:

The smaller one.

To Mother Farm

If I wait here, the next bus is one hour forty minutes away.

Let's continue to Mother Farm.

The Mount Kanozan tower cluster. Passing it by today: the prefecture, the Ministry of Land, Infrastructure, Transport and Tourism, and the National Police Agency.

Arrived after 35 minutes.

Mother Farm

What I want to do:

• Look toward Mount Kanozan;

• Check the microwave relay stations for any suspicious new branch.

Those are the objectives.

Looking toward Mount Kanozan

A high spot on the climb toward the hilltop gate.

The Mount Kanozan tower cluster can be seen from here.

Like this.

JOSADA TELECOM. You can also see the HF antenna mounted on it.

Microwave relay stations

This is one of the relay points connecting the Chikura cable landing station to Toyosu's data centres by microwave, with lower latency than fibre.

From here, long-haul space-diversity links cross Tokyo Bay.

JOSADA TELECOM makes its shot from the tower discussed here, farther east on Mount Kanozan.

Glad to see everyone is doing well.

There do not seem to be any new branch links either.

●HBC: High Bar Communications

https://www.tele.soumu.go.jp/musen/SearchServlet?pageID=4&IT=A&DFCD=0004121752&DD=1&styleNumber=21

https://www.google.com/maps/@35.2478688,139.936534,52m/data=!3m1!1e3

●GTT: GT Technologies

https://www.tele.soumu.go.jp/musen/SearchServlet?pageID=4&IT=A&DFCD=0003997875&DD=1&styleNumber=21

https://www.google.com/maps/@35.2464086,139.9359735,52m/data=!3m1!1e3

●NuVo Networks

https://www.tele.soumu.go.jp/musen/SearchServlet?pageID=4&IT=A&DFCD=0004176361&DD=1&styleNumber=21

https://www.google.com/maps/@35.2459382,139.9335434,52m/data=!3m1!1e3

JS2SB is connected into NuVo's network through this antenna ↓.

In the photo above, it is the tiny right-facing antenna on the upper level.

Back to Tokyo

Mother Farm 12:45 → Sanukimachi Station 13:08.

Sanukimachi 13:29 → Kimitsu 13:48 / 13:50 → Shimbashi 15:26 / 15:32 → Tamachi 15:37.

Mother Farm.

Mount Kanozan from Sanukimachi Station's footbridge.

From left: NTT; the Ministry of Land, Infrastructure, Transport and Tourism; Chiba Prefecture; two National Police Agency towers; and JOSADA TELECOM standing apart on the right.

JOSADA TELECOM's tower.

Sanukimachi.

Kimitsu.

Shimbashi.

Expenses

¥1,782: JR, Tamachi → Sanukimachi.

¥300: Tokyo Bay Kannon admission.

¥650: bus, Sanukimachi Station → Jinyaji Temple.

¥550: bus, Mother Farm → Sanukimachi Station.

¥1,782: JR, Sanukimachi → Tamachi.

――――――――――――――――

¥5,064 total.

Comparing all the stations

An update to the table in the earlier post ‘The Shimoizumi log-periodics, continued’: https://jj1wtl.seesaa.net/article/519392776.html (English translation)

Antenna installations*** and microwave licences (the original groups these by company):

*: Licence renewed.

†: Additional counterpart destination.

**: Additional frequency.

††: Power increase/decrease.

***: Log-periodic unless otherwise stated.

†††: HF: experimental stations;

SHF: fixed stations in the 6 / 7 / 14 GHz bands;

EHF: land mobile stations in the 80 GHz band, permitted to move.

Other, receive-only operators

Omitted above for space.

Including these two ↓, there are eight companies altogether:

There is a Yagi on JOSADA TELECOM's Mount Kanozan tower, as in the photographs above.

The SteppIR one that is not the ‘tape-measure’ type.

However, it has not yet reached the full-licence stage.

Updated overview diagrams

Updated the photographs.

Added JS2SB's antennas.

Earlier posts

‘JS2RA / JS2RB’

https://jj1wtl.seesaa.net/article/499204144.html (English translation)

‘JS2RA / JS2RB, continued’ (additional Philippines-bound Yagi)

https://jj1wtl.seesaa.net/article/505776879.html (English translation)

‘JA/CB-004’ (4HF's JS2SA and HBC's JB2XH, later classified as a receive station)

https://jj1wtl.seesaa.net/article/499505940.html (English translation)

‘JS2SA / JB2XH’

https://jj1wtl.seesaa.net/article/500304565.html (English translation)

‘The new JB2XH’ (transmit station)

https://jj1wtl.seesaa.net/article/504743515.html (English translation)

‘JS2SB’ (licence information)

https://jj1wtl.seesaa.net/article/505386673.html (English translation)

‘JS2SB, continued’ (site photographs)

https://jj1wtl.seesaa.net/article/505597775.html (English translation)

‘JS2SB, continued again’ (building application)

https://jj1wtl.seesaa.net/article/511302814.html (English translation)

‘The Minamihara log-periodic’ (NuVo Networks)

https://jj1wtl.seesaa.net/article/501355072.html (English translation)

‘The log-periodic at Cosmo Classic Club’ (GTT)

https://jj1wtl.seesaa.net/article/508688232.html (English translation)

‘The loop array at Maeda, Minamiboso City’ (Ermis, reception)

https://jj1wtl.seesaa.net/article/515801449.html (English translation)

『JB2XI』

https://jj1wtl.seesaa.net/article/505733007.html (English translation)

‘The log-periodics at Shimoizumi, Sodegaura City’ (Ermis, transmission)

https://jj1wtl.seesaa.net/article/516751748.html (English translation)

‘The Shimoizumi log-periodics, continued’ (licensed)

https://jj1wtl.seesaa.net/article/519392776.html (English translation)

‘Microwave routes — Wakasu’ (DATACOM SERVICES and Ermis connections to the data centre)

https://jj1wtl.seesaa.net/article/517567284.html (English translation)

‘The Beverage antennas at Nuda, Kimitsu City’ (JOSADA TELECOM, reception)

https://jj1wtl.seesaa.net/article/518223542.html (English translation)

‘The Yagi on Mount Kanozan, AVANT 1’ (JOSADA TELECOM, transmission, before mounting)

https://jj1wtl.seesaa.net/article/519469435.html (English translation)

‘The Yagi on Mount Kanozan’ (JOSADA TELECOM, transmission)

https://jj1wtl.seesaa.net/article/519927784.html (English translation)

Comments

Translated from the comments in the archived original HTML. Author names and timestamps are retained as displayed; these are separate from the article.

JH5TEY — 2026-08-24 14:11

This is my second comment. I enjoy reading the updates every week. I also look forward to your explorations of the Ise-Shima and Kitakyushu routes.