Alcator C-MOD Weekly Highlights March 11, 1997 A major milestone in the assembly process was passed this week when the 44,000 lb cylinder was installed on Alcator C-Mod. The cylinder must be in place before we can begin the installation of horizontal extensions and ports, and the ports are in turn required before some of our invessel work can be completed. A great deal of work was done last week in preparation for the cylinder. Spring plate installation was completed, TF leg backing plates were installed and trimmed to size, shims were installed on the TF arms and legs, thermocouple and heater connections were checked, and joint to joint measurements of resistance were made on the TF magnet. A very thorough cleanup of both the machine and cylinder was also required. As the last invessel components have been fabricated, baked, cleaned, and leak checked, we have begun to concentrate our efforts inside the machine. Support hardware for some of the new periscopes has been installed. Alignment and calibration of the new edge, high spatial resolution, x-ray array has been completed, and work is moving rapidly on other high resolution edge diagnostics. The JHU divertor spectrometer has been fit up invessel and is ready to install. Much work was done last week on the new transmitter installation. The FPA cavity for transmitter #3 had been assembled and the water cooling is being connected to both transmitters #3 and #4. We have also begun to test transmitter #4 at low voltage levels. PLC and Paragon programming for both new transmitters continues. Fiber optic cables for CAMAC and PLC signals involved with transmitter data acquisition and control are being installed to link new RF systems in the power room, cell, and control room. The checkout of the TF power supply is complete. The regulator was tested, and the new "hard limit" inversion clamps were checked for proper operation. The TF crowbar was checked for proper gate firing, fuse continuity, and overvoltage detection and annunciation. The high and low tap transition was checked. With completion of the TF work, the inspection and checkout of the OH1 supply has begun. Progress on the DNB system included installation of the new ACCEL supply in the power room. We are now setting up to vacuum degas and filter the oil for both the new supply and the filament/bias supply, and a checklist is being developed to bring up the new supply and make it operational. John Heard from Auburn has arrived at C-Mod and will be based here setting up the O-mode radiometer for the spring run campaign. He will also develop an E-mode radiometer in the longer term. Roger Bengston from U. of Texas is visiting this week installing hardware for his new scanning probe. Sean Regan and Mark May from JHU have been here installing the new divertor spectrometer. Miklos Porkolab was in San Diego last week at the Iter Scientific Council to the US Home Team (ISCUS) meeting.