New World Distance Record Claimed on 122 GHz

A new world distance record of 139 kilometers (86.2 miles) is being claimed by radio amateurs in northern California. This tops the record of 114 kilometers set in 2005 by WA1ZMS and W4WWQ, according to the Distance Records on the ARRL website.

The February 17, 2020, contact was between Mike Lavelle, K6ML, on Mount Vaca (CM88WJ75ON) at 835 meters (2,739.5 feet) above sea level, and Oliver Barrett, KB6BA (at 1225 UTC), and Jim Moss, N9JIM (at 1250 UTC), both on Mount Umunhum (CM97BD18VJ) at 1,016 meters (3333.3 feet) above sea level.

Lavell reports the dew point was –11 °C, the air temperature was 15 °C, the path loss was about 225 dB, and atmospheric loss was approximately 0.35 dB/kilometer.

“CW was used, 122 GHz signals were very weak (7 dB above the noise in 22 Hz; –13 in 2500 Hz equivalent) with [fading] down to the noise floor,” Lavelle told ARRL. “Dishes were aligned on 24 GHz (71 dB above the noise) prior to [moving] to 122 GHz; we heard signals right away on 122 GHz.” The stations employed 60-centimeter satellite TV dishes and ran “somewhat less than half a milliwatt” on 122 GHz, Lavelle said.

Source:ARRL