122, 134 and 248 GHz
The three highest frequency bands in the UK amateur license are 122, 134 and 248GHz.
- 122 GHz is a secondary allocation and suffers from high Oxygen attenuation (similar to 60GHz)
- 134 GHz is a Primary band that is the preferred operating band for new portables
- 248 GHz can earn large multipliers in IARU contests, but is more difficult to obtain equipment for
At 134GHz, harmonised narrowband activity centre is nominally at 134.928GHz, but in practice 134 and 241GHz operation is dependent on convenient multiples from synthesised/multiplier local oscillators which are chosen for best frequency stability and low phase noise etc. The telescopic site in the photo is an essential accessory as narrow beamwidths make alignment/pointing accuracy a challenge.
Note that in the UK, no operation is currently permitted on bands above 275GHz (the THz bands).
At even higher frequencies Free-space Lightwave activity is permitted as that occurs above the frequency limits in the ITU Radio regulations.