To: Edgar Castro

From: Jon Hagen

Date: Nov. 3, 2000

Subject: Report for October, 2000

I have made considerable progress in learning and documenting the Vertex software. I have used the spare PLC (Programmable Logic Controller) crate, PLC CPU, and the spare digital output module to create test programs, edit them, test them, and burn them into a spare flash memory module. The proprietary Vertex software modules have been unlocked in order that the system can be completely documented. Next month I hope to finish the flow charts and a written description of the PLC code.

In preparing the waveguide system for the new 430 MHz Gregorian transmitting capability, the old 430 collector was retuned to reduce its return loss. The new slotted line and the new run of half-height waveguide from the collector to the dome were tested and found satisfactory. These components and the 430 MHz horn in the Gregorian were tested successfully up to 1MW (limited at that point to protect still-vulnerable radio astronomy receivers in the dome).

Some work was done with Bill Sisk and Phil Perillat on the servo control algorithm to be used in the tertiary reflector drive system.

I delivered the talk about the Observatory at the plenary session of the IEEE International Ultrasonics Symposium in San Juan. Two days later, 42 conventioneers arrived in a Tourism bus to take a first-hand look.