Dear AMMRL,
We have been having communication issues on our MercuryVx 300, and I was
hoping that one of you might have some suggestions.
Diagnosis/Symptoms:
1) Acqstat always reads as "Inactive"
2) On console boot up we see interaction with the "inova" Ethernet
card via ping for 8 to 24 seconds
3) On "setacq" execution we see interaction with the "inova"
Ethernet card via ping for 8 to 24 seconds
4) Communication stops after this initial 8 to 24 second period
Probe/Investigation/Troubleshooting
We have a spare Mercury 400 and two Inova 400's in our lab which
we can borrow parts from for diagnosis purposes.
1) Swapping ACQ/CPU board | No effect
2) Swapping hme0 for hme1 (Ethernet ports on the UNIX box)| No
effect
3) Swapping swift Ethernet cards between two UNIX boxes | No effect
4) Swapping Ethernet cables | No effect
5) Swapping RJ45 to serial conversion box | No effect
6) Swapping ACD & STM Output board | No effect
7) Swapping Junction Board | No effect
8) Removing subethernet comms (VTController and Spin Regulation
board) | No effect
9) Reset of Spin Regulation board | No effect
10) Swap of the Spin Regulation board (ran a long crossover Ethernet
cable from one instrument to the other instrument magnet leg) | No
effect
11) Rebuilt the UNIX box from ground up, including reinstallation of
VNMR and users | No effect
12) Swapped Inova400 UNIX box in for the MercuryVx 300 |
Communications Alive (Ping active for more than 5 minutes)
13) Execution of "su acqproc" | Returns typical "Killing"/"Starting"
messages but No effect on the problem
14) Execution of "setacq" | Reinitiates active ping for 8 to 24
seconds and then quits
15) The power to the digital card cage mostly appears nominal, two
of the +5.0V lines measured in at 5.3V
16) The power to the RF card cage mostly appears nominal except the
-11V leads measure at -11.8V
17) None of the power supply measurements had significant digital
ripple
18) "snoop"ing on hme1 reveals information consistent with the ping
data
19) "netstat" shows that the class A network is in order for the
"inova" comms device.
20) The 40.5 MHz system reference frequency is shaped more like
positive and negative wavelets occurring with sinusoidal periodicity
than a sine function. I have not compared this shape to the other
Mercury system in our lab.
Thanks in advance,
Don Eldred
NMR Analytical Specialist
Dow Corning Corporation
2200 W. Salzburg Rd.
Auburn, MI 48611
Phone: (989) 496-6843
Fax: (989) 496-5121
Received on Wed May 24 2006 - 11:17:23 MST