Just like the rotating beacon at the airport, the two lights
are 180 apart and rotate on the common shaft.

Yes, you could have just one light rotating, but two
identifiable beacons makes the system more useable and
faster.

English lesson... "white beacon passing North...green beacon
sweeps by" Seems that both are moving.



"Mark Hansen" wrote in message
...
| On 06/13/06 11:15, Jim Macklin wrote:
| You can explain how a VOR/DME works with a simple visual
| model.
|
| There is a large lake with an island in the middle.
There
| is a lighthouse with a rotating beacon that makes one
| revolution a minute. It has a white beacon and a green
| beacon, when the white beacon is passing North, a big
strobe
| light on top flashes and a very loud horn sounds.
|
| You see the strobe light flash and 6 seconds later see
the
| green beacon sweep by. Where are you? 216 degrees from
the
| beacon. Ten seconds after the strobe, you hear the
horn,
| how far away? 2 miles.
|
| So are both the white and green beacons rotating?
|
| Don't you just need an omnidirectional strobe (with horn
for
| distance measurements) and a single rotating beacon?
|
|
| VOR is the same, just faster.
|
|
| Steer your boat so the bow always points to the light
and
| you've got an ADF homer.
|
|
|
|
|
|
| --
| Mark Hansen, PP-ASEL, Instrument Airplane
| Cal Aggie Flying Farmers
| Sacramento, CA