MICROWAVE UPDATE
27-30 September 2001
|
THURSDAY
27 SEPTEMBER:
AFTERNOON
VISIT TO THE STANFORD DISH
|
After the surplus tour we had lunch and then joined
a convoy of cars to drive several miles out of town to the 150 foot diameter
dish at the Stanford University site. This was an incredible sight as the
following photos show....
 |
As
we drove up the road leading to the dish, it came into view like
something from a science fiction movie. The scale can be estimated here
by comparing the size of the car in the background with the dish. |
The aim of the visit was to see the dish of course
but also to experience amateur EME ("moonbounce") via the 23cm band. Jeffrey
Pawlan, WA6KBL had, all by himself, organised an EME test for the late
afternoon and we were hoping to hear some really good signals via this
mode.... we were not disappointed! He had spent more than a week wiring
control systems to work with the existing cabling on the Stanford dish
and testing every item.
The dish dwarfs everything
around it! It's several decades since it was put together but it still
functions well. Seeing it brought back memories of the pioneers of amateur
"moonbounce" ... people like Sam Harris of W1BU and Arecibo dish fame back
in the late '50s and '60s.
The Stanford dish is
shown here with the feedhorn support arms lowered to the ground.
Lowering the feed support
this way would also work in a much more modest amateur system, allowing
quick change of feeds and transverters mounted at the feedpoint.
|
 |
 |
Paul
Wade, W1GHZ, admires the 23cm feedhorn. He's probably wondering how it
would look on his computer simulation software!
Notice the feeder cables
and other control lines. Remember that the operation position is in the
building behind the dish ... a long way from this feed! |
| As
a result of the long feedline it is imperative to mount the "front end"
of the 23cm transverter at the feedpoint. Here Jeffrey Pawlan makes some
final adjustments to the PA. |
 |
 |
Later,
after the 23cm amplifier had been installed for the test, the arms were
raised into the operating position. |
With the dish ready for use it was time to go inside
the "shack" to see what was going on 23cm ... so over to the next page
...
|
