[evlatests] ea26 failed

[Steven Durand]

EVLA antenna26 failed the electronics acceptance test today.

The xband receiver is weak which requires the gain to be turned up to 
the point that the switched power is higher than normal.  This is a 
function of the receiver so we will have to live with this.

Lband IFd is has low 8bit RMS power into the D351d.  This is probably 
just a level setting problem in the T304.

The real problem is the Kband noise diode system is sad.  The noise 
power reads 4 times what it should (8 volts instead of 2 volts) on all 
IFs. FE reports that the noise power at the receiver is about 2%, as it 
should be.  FE looked at the 28 v drive voltage and it seems OK.... but 
something is sad.

There are no other receivers.

There is no round trip system.
-- 


Steven Durand, MTS               National Radio Astronomy Observatory
Electronics Division             1003 Lopezville Road
505.835.7103                     Socorro, New Mexico  87801