[evlatests] Wednesday P-band satellite test

[Paul Harden]

To whom this may concern:

Wednesday, Aug. 26 around noon, the ten VLITE antennas will be pointed 
for the VLA over-flight of the Cassiope satellite for about 20 minutes.  
This is not a science test, but more engineering/electronics in an 
attempt to characterize compression points in the system should that 
occur.  Power detectors and other data will be logged during the 
over-flight.  The WIDAR correlator will not be available or used for 
this test.

This is a joint test between the VLA, NRL and the Cassiope satellite 
operators.  Normally, the P- and C-band transmitters on Cassiope are 
automatically turned off when it flies over the VLA.  The P-band 30 watt 
transmitter at 410 MHz will be turned on for this test on the target 
pass only.   NRL estimates the received power to be 10^14 Jy, which 
should just be below the compression point of the LBR receivers, and a 
possibility of compression in the upconverters or T304/T305.  We just 
don't know -- the purpose of this test.  The "bell curve" formed as the 
source passes through the beam should tell us at what power level 
compression or intermod distortion occurs, if it does.  Data will also 
be remotely monitored by NRL.

The VLITE antennas will be pointed to a given AZ-EL and allow the 
satellite to drift through the beam.
12:07 pm MDT (1807 UTC) - time of rise (EL=0 degrees); antennas will be 
pointed
12:20 pm MDT (1820 UTC) - pass through the beam (EL=36 degrees, 
approximate maximum received power)
12:27 pm MDT (1827 UTC) - time of set (EL=0 degrees); antennas will be 
stowed

The 10 VLITE antennas are: EA05, 06, 09, 10, 11, 12, 14, 18, 19, 23

If any personnel are on the above antennas on Wednesday Maintenance Day, 
it would be appreciated if you could temporarily leave the antenna for 
the 20 minutes of the test around noon.  If work is in progress 
rendering it unsafe to point the antenna, we will simply not use that 
antenna.

If anyone else has reason to monitor these antennas while exposed to 
such a strong RF source, feel free to do so.

If any questions, let me know.

Paul Harden