Alcator C-MOD Weekly Highlights
			November 13, 1995

Recommissioning activities have been completed, and Alcator C-MOD is now
ready to begin our fall operating campaign.  This report covers the two
weeks from October 30 through November 10, 1995. 

Full system checkouts were carried out during the week of October 30,
including initial plasma operation. In addition to verifying proper operation
of power supplies and control systems, these tests provided an opportunity to
begin checking out diagnostic systems. Several full length 600kA plasmas were
produced as part of the checkout process. 

Much of the week of October 30 was spent commissioning the "new" EF4 power
supplies. These Robicon units, formerly used on the TF coil of Alcator C/MTX,
have now been moved over to C-MOD to allow increased current on the EF4 coil,
while the TMX supplies formerly used for EF4 have been added to the EF2
complement, to permit higher currents on those coils as well. In their new
application, the Robicons are configured to provide four-quadrant operation.
Difficulties encountered with the crossover circuitry were traced to poor
signal to noise on the internal shunt signal used in the control logic. This
situation was remedied by replacing the shunt with one of higher resistance
and applying additional filtering. These changes were successfully tested
using prototype circuits on Friday, November 4, and the permanent
modifications were implemented and tested the following week. 

Acceptance tests of the new transformer of the EF1 power supply were carried
out at the vendor's facility last week. Delivery is expected this week. The
new transformer should allow higher voltages to be obtained from this supply.
Voltage limitations on EF1 were identified during the last campaign as a
contributing factor in a significant number of high halo current disruptions. 
 
The source of crosstalk in the TF coil scanner was identified and eliminated. 

The shot-permissive logic associated with the TORVAC PLC was modified to
permit a pulse-gas only startup, rather than using a steady fill. This
scenario, which we have now successfully tested, will be required for
operation with boronized walls, as well as with in-vessel cryo-pumping. 

The vessel mockup, to be used for fitup of the cryo-pumping hardware, has been
completed and sent out for electro-polishing. 

Most of the C-MOD physics staff attended the APS-DPP meeting in Louisville,
KY, last week. Presentations by Alcator staff and our outside collaborators
included three invited talks, ten contributed talks and thirty-five posters.