[evlatests] Antennas 13 and 14 Status

[Jim Jackson]

We repaired one of the L302 synthesizers brought back yesterday.  Jerry 
will be installing it in Antenna 13 today.  That should get IF's B&D 
running again.

Jim

At 02:01 PM 4/10/2006, Jim Jackson wrote:
>Antenna 14:  Jerry and Leon did verify that, as suspected, the 128MHz 
>input power to the L302's was low by about 3dB due to the production L305 
>that was installed last week.  All production units are trimmed to have 
>the identical output power but apparently the prototype unit had slightly 
>higher output power.   They readjusted the levels and resync'ed 
>everything. Based on past experience, this was just low enough to cause 
>erratic operation of the L302. Please try using the antenna to see if 
>correcting this helped the IF B & D issue. Hopefully, this antenna is 
>fixed now. If not, we will have to remove the L302-2 synthesizer for testing.
>
>Antenna 13:  They tried replacing the L302-2 with the second unit from 
>Antenna 18 (which was sitting in the rack powered off). Unfortunately, 
>it's MIB would not come up on the network with module ID.  They are 
>bringing both units back for repair.  After a short discussion with Rick, 
>we decided to leave both Antennas 13 & 18 functioning with IF's A & C 
>rather than breaking antenna 18 to fix antenna 13. So right now Antenna 13 
>does not have B & D IF's. We will try to fix one of the synthesizers and 
>get it back out there tomorrow or Wednesday.
>
>Jerry also discovered a timing cable was not connected to the L302-1 in 
>Antenna 13. This would certainly have caused some problems with IF's A & C 
>and has now been fixed.  You may want to try running this antenna to see 
>what effect this had. If both synthesizers were not working, it could 
>explain the results from the weekend.
>
>Jim
>
>
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