The NAHA marathon was held in Okinawa on December 3 with 24,000 competitors as below and it took 25 minutes from the start of signal gun to the last runner.

Our Japanese timer arranged aerial antenna for this race and they were able to measure all of timing perfectly.

This application was great successful example of antenna in this year!!

Aerial antenna

J-chip had an interview to timer about actual condition of this antenna as follows.

"The height of aerial antenna is around 2.8m from ground surface and length is 10m.

Original height was a schedule of 2.5m but we changed to 2.8m because some runner who entered for carrying piggyback had been expected.

The width of the trigger antenna cable are 1m with two times loops and sensitivity was from the ground surface to 5cm. The indicator of level meter showed 30 micro A.

In case of 1 time loop, sensitivity was from ground surface to 50cm. (The indicator of level meter showed 25 micro A)
We arranged 8 pcs of dipole receiver antenna in the middle of the trigger antenna however the sensitivity distribution area extends in the air, it might be acceptable even by only 5 or 6 pcs of dipole receiver antenna.
We tried this 10m length antenna to bike race and it was possible to measure it even by the bike race with perfectly.

The width of the road was 6m at this time so both ends of the cable of 10m were hung down and measured, we surprised that sensitivity became more sensitive."

Start of NAHA marathon

The first runners stand by at start line beautifully. Is it a Japanese character?
The judgment on a right edge is warning the one competitor because his foot run over just little from start line.(That's scary!)