[amsat-bb] Re: antenna rotator test

Stan, W1LE stanw1le at verizon.net
Mon Nov 8 16:55:54 PST 2010

Hello Nayer,

I have not seen any other's response, so, here is mine....
Performance verification, one step at a time.

I verify performance and calibrate all scales before the positioners are 
put on the tower.

Start off reading the instruction manual for operation and maintenance.
Replace any corroding hardware as needed, one piece at a time.
Be sure all hardware is torqued properly and NOT loose.
Do not hesitate to grease all threads with a tenacious axle grease, all 
aseembly bolts/screws and clamps.
The grease allows you to take stuff apart 10 years later.

Before connecting anything, measure the resistance of the AZ and EL 
internal position indicating potentiometer.

Do the numbers agree with the manual ?

Measure the motor winding resistances. Do both the AZ and the EL 
  Document findings. Is the manual in agreement ?

Determine how much rotator control cable length you will need
Sketch out a wiring diagram and document the wire color scheme you will 
be using.
(My 8 conductor rotator control cable uses 8 different colors.)

Assemble the cable to the AZ and EL rotator with the actual length of 
rotator control cables to be used.
Do not add antennas at this time. Orient the AZ and EL positioners as 
they would be used.

Measure the resistance of the AZ and EL motor windings, with the cable 
attached, at the controller end of the cable.
Measure the resistance of the indicator potentiometer for both AZ  and EL.
Document your findings.  Are readings reasonable ?   Correct any problem.

Wire up the control cables to the controller and add a means of 
measuring the AC current to the controller.

Apply AC power to the controller and note the AC current draw.
Exercise the AZ rotator, verify that the AZ rotator turns clockwise or 
counterclockwise as activated.
Note the AC current when the AZ rotator is turning. AC current should be 
the same CW or CCW rotation.
Is the azimuth indicator going thru it's entire display range ?
Calibrate the AZ display according to the manual. Verify position range 
after any adjustments.
Some AZ controllers only go 360 degrees +/- a few degrees , some go more.
Park the AZ positioner at one end of its rotation. I call this NORTH. 
(0.0 degrees true north)

Exercise the EL posioner, Calibrate the display as indicated in the manual.
Not the mechanical noise to the AZ or EL motor turning.
Measure AC current to the positioner as the EL motor is turning max 
speed. Document.
Park the EL positoner at 0.0 degrees elevation.

Measure the AC or DC current from the controller to the AZ and EL 
positioner, document.
Measure the voltage at the controller output, no load and full speed 
positioner load
Disassemble and reassemble on the tower. Add the antennas
Slip the mast for 0 degrees true north. Torque down the mast clamps
Slip the boom for 0 degrees elevation. Torque down the boom clamps.

Exercise the AZ and EL over its full range. Measure AC current to the 
controller with antenna loading.
Measure the AC or DC current from the controller to the positioner, with 
antenna loading.
Document findings.

Play satellite.....

I hope this helps

Stan, w1LE     Cape Cod     FN41sr

On 11/8/2010 7:37 AM, N. Mahdinejad wrote:
> Dear all.
> Thanks for Bob W7LRD and Greg D for answering to my last question.
> Is there any standard document or other for test antenna rotator? Some
> functional and environmental tests.
> If anyone is familiar with these tests, please send me a link to read or
> download some useful documents.
> Any help would be gratefully appreciated.
> Best regards.
> Nayer Mahdinejad.
> _______________________________________________
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