Home Astronomy Bicycle Construction Laser Moonbounce Software Guest Misc Sales

Using Communcations towers as LASER Reflectors

View from right under tower

635 nm 6.4 mw laser fired through
ETX-70 telescope as a laser collimator
and focused on dish E4 from K3PGP.
This is a bit over a 5 mile path.
Note the size of the red laser dot!

This tower has been used to communicate
over 30 mile paths from sites that are not
line of sight with each other but both could
see the same dish on the tower.

The diameter of the laser dot can be spread
to the diameter of the dish before there is
any loss of signal strength. This makes the
reflection less visible which may be an
advantage in some cases. :-^)

Above photo taken with consumer camcorder
looking through 25mm eyepiece of ETX-90.

Tower viewed from
K3PGP earlier in day
Larger red dot is same
laser using smaller

Above photo:
Consumer camcorder
internal optics at 40X.

View from another site.

Consumer camcorder
using built in optics at 40X.

Laser turned OFF

View from K3PGP
Red dot is same laser using smaller collimator which produces a larger diameter beam.
I believe it was hitting the metal shroud on one of the lower dish antennas which is why the reflection is brighter even though the laser isn't collimated as well.
Red light at top of tower is a beacon light. The laser reflection is the dot near the bottom of the tower. There are no antennas at the top of the tower that are large enough to use as a reflector.

View from another site.
Laser was NOT turned on at this time.

Home Astronomy Bicycle Construction Laser Moonbounce Software Guest Misc Sales

Contents of this website are 1995-2012 of K3PGP and of the originating authors.