My first SOTA activation in Japan – Shiroyama 13 Feb 2016

The first SOTA summit I climbed during my visit to Japan was Shiroyama JA/KN-022. This summit is on the western outskirts of Tokyo and just over the border into Kanagawa prefecture. And climb it was as the bus drops you off a little above sea level. The summit is at 375m elevation rising up steeply from the flatlands of Tokyo.

Public transport to the summit is very convenient. Take one train from the major station Shinjuku in Tokyo until the end of the Keio Sagamihara line at Hashimoto (station KO45). Then take the Hashimoto 01 bus for Mikage to stop 14 at the base of the mountain called Tsukuiko Kanko Center mae (35.58643N, 139.280824E). Timetable and route is here. Once starting the climb, there are maps available en-route.

Near the top there is a faux-peak with a small shrine. One then walks down a little and up again to the real peak which has a cleared area at the top (35.5831N, 139.2787E). I set up just to the side of this clearing.


My station consisted of a linked ground plane antenna that I had made that day after scouring Akihabara for parts. It had links for 40m, 20m, 15m and 10m. The radials were designed for 20m. A tree provided the top support for the vertical section of the ground plane.

The radio used was the KX3 on internal AA alkaline batteries.With such a small power source the radio could only be used QRPp and I started out at 3 Watts. With the 6m/10m SOTA challenge in its last day, I set up on 10m at first.On SSB I was rewarded with 5 contacts: JJ1SWI/1, VK4RF, VK4HA, JA1JCF and 7K1WRK/1. I tried CW too but made no contacts in that mode. Callsign used was JR2YFM/1. QTH locator: PM95pn.

Lowering the vertical, I joined up the first pair of wires and was then on 15m. On that band I made one contact with JJ1SWI/1 again. The radio was starting to shut down during transmit occasionally so I had dropped the power to 2 Watts. Seemed unusual to only have one call on 15m, however, there may have been no propagation. JJ1SWI is local to Tokyo so it was a ground wave contact.

Next was 40m and two more links were joined in the antenna. On this band there was another call from JJ1SWI/1 at about the same strength as on the other two bands. I had reduced my power down to 1 Watt at this stage.

For the final change it was to 20m CW and after dropping the antenna and removing a link I was rewarded with a call from Rick VK4RF and his alter-ego VK4HA. Sigs received on this band were 58 from Rick so quite a bit stronger than on 10m. The difference was that I worked Rick using 3W on 10m but only 1W on 20m.

With little battery left and the light fading fast I had to pack up quickly and drop down the mountain. It took about 30 mins to climb to the top and about 20 mins to descend. With a 3 minute wait for the bus I was on my way back to Tokyo. Allow 90 mins to get to Shinjuku station.

So, a very successful activation. Although I made 4 contacts on CW, there were only 3 unique stations so I am yet to qualify on CW. I well and truly qualified on SSB. This is a very easy one to activate if you are in Tokyo as the public transport is so convenient. The only difficult thing is the climb. Remarkably, there is no QRM at the top of the mountain. Nice views of the dam and countryside below too.