"Keith W" wrote in message
...

"Stubby" wrote in message
. ..
Bob Moore wrote:
"M. J. Powell" wrote


Except ICs instead of valves?


It wasn't the size of the electronics, but rather the
large antenna array required of the VOR system. A VOR
antenna must be permanently aligned to the earth,
something not possible with such a large array onboard
a ship. The TACAN system operating on a different principle than VOR
solved the size and alignment problems.


Bob Moore
Can you either explain how a TACAN works or provide a reference? Thanks.

There's a nice writeup at

http://www.radarpages.co.uk/mob/nava...can/tacan1.htm


Here is another description that explains how the VOR ground station signals
are used to determine the radial.

http://www.answers.com/main/ntquery;...a&linktext=VOR