[Paul_Sengupta]

I don't know about the offset carrier operation side of things

http://www.pprune.org/tech-log/108843-vhf-offset-carrier.html

[Flying_john]

Offset carrier is a poor mans solution to lack of radio channels or using the more expensive system of Quasi Syncronous wide area radio coverage on the same frequency.

https://en.wikipedia.org/wiki/Quasi-synchronous_transmission
This method woud be the only practical solution if the same 8.33 frequency is to be used from multiple base station sites although it is preferable to use FM to take advantage of the capture effect, it has been used in AM systems.

[wigglyamp]

Offset carrier on AM 25Kz has been used for years in the UK. When the B757 was introduced in 1983, we had problems at BA with aircraft flying the LHR to Edinburgh or Glsgow shuttle losing comms over the Lake District as their new radios couldn't cope with the offset carriers so the squelch didn't lift for an incoming signal!

Some more info: http://www.icao.int/safety/acp/acpwgf/a ... v1r0_4.pdf

[JonathanB]

Sorry, I should have said I don't know how or if it works with 8.33 - I realise it's use on 25kHz.

But as I said, we cross-couple different frequencies together so transmissions received by the ground station on one are re-broadcast on the others so situational awareness is maintained.

[nje]

I've read quite a lot about this grant and read the reminder about it in the flyer magazine but I cannot find any information about ' how' to apply for it. Can anyone help me out with this please?

[stevelup]

Nothing has been published yet by the CAA

[nje]

Thanks for your reply Steve , I thought I'd missed it