To: Edgar Castro

From: Jon Hagen

Date: 10-7-99

Subject: Monthly report for October '99

Mechanical designs sent to the Ithaca lab for fabrication include a 430 MHz half-height waveguide calibration kit (three waveguide shorts), a half-height waveguide-to-coax transition, and a half-height turnstile. The calibration kit will be finished first, as it will be needed for the installation of the waveguide run through the dome to the feed room. Drawings have been made for the entrance of the new waveguide feed room, its run across the ceiling, and, finally, its connection to the new turnstile junction on the feed horn. Shop drawings for the fabrication of the new collector (pickup unit that moves in the slotted waveguide below the azimuth arm) are still to be done. Meanwhile, however, the maintenance department has repaired the damaged spare collector. If necessary, this unit can be installed on the Gregorian side until the new collector is ready.

The larger motors have been installed in all three tie-down systems and have solved the problem of inadequate torque. Work continues to improve the lightning protection on these systems. Better ground rods have been installed. A more complete set up bonding wires will be installed to better protect the encoders on the jacks.

At the suggestion of Monty Grimes (MIT Haystack), we have arranged to have a damaged 430 MHz klystron rebuilt by California Tube Lab in Watsonville California. If this is successful, a second tube will be rebuilt and kept as a spare to keep our transmitter on the air until surplus tubes become available from the deactivated BMEWS radar at Clear, Alaska.