receiver maintenace

file: rxmain.wp6 jbh 4-28-00

Given that we must maintain N reciever systems

For each system we should have

1. Substitute receivers, ready to be installed. Maybe even kept cold

in the receiver test range building where their performance is monitored.

1a. Best possible position for substitute receiver is another position on the turret.

An extremely critical receiver (the most used receiver) could have a permanent back-up, resident on the turret.

2. Test Dewar: Probably need one if we are doing amplifier development. But given that we only buy the LNAs and mount them in custom mount them in dewar packages, the spare dewars provide custom test stands for each amp. Obviously these are the best test stands, since they are part of the system. How might we modify our dewar designs to make them more useful as test stands? SPST switches at amp inputs that go to coax inputs?

3. Calibrated cold loads for testing. Probably the sky. If so, we need a narrow-angle skynoise horn for each receiver. Maybe we need a water vapor monitor to better judge the sky temp on the day of any given measurement.