[Milsurplus] Re: SCR-274-N Transmitter Dial Accuracy

[Mike Andrews W5EGO]

On Tue, Jul 08, 2008 at 03:35:54PM -0500, Mike Morrow wrote:

> In the early 1950s the standard civil air-to-tower frequency changed
> to 3023.5 kHz.  That frequency today is officially assigned for search
> and rescue use.  I don't know why 3105 was changed, but 6210 kHz must have
> been lost at the same time, since most of the simple transmitters just
> doubled a 3105 crystal to get the 6210 frequency.  I don't know what
> 3105 kHz is assigned for today.

The FCC allocation chart just shows 3.025 to 3.155 MHz as "Aeronautical
(OR)"; I'm having trouble finding the meaning of "OR".

-- 
Mike Andrews, W5EGO
mikea at mikea.ath.cx
Tired old sysadmin