Ara! Onara suru tsu-mori datta keh-do, un-chi ga de-chatta...
As reported previously, the transfer functions of the channels look fine. (i.e. All channels almost identical.)
I checked the chain from the unit input to the DAQ BNC connectors. They were all OK.
Today I have been checking the signals on the unit with the long DB37 cables connected.
I could not see anything on the Gur2 channels on the board. I looked at the DB37 for Gur2 and felt something is wrong.
I opened the housing of the cable and realized that all the pins are not fully inserted.
The wires were crimped improperly and prevents them to be fully inserted.
=> We need to redo the crimping to insert them.
=> We need to check the other side too.
I'm making a new long cable. Both connector ends of this X arm long cable were terrible. It was removed from the cable tray yesterday.
The Y arm Guralp is running fine. The interface box is open in front of 1X1 on a cart and it is alive! Please be aware of it !
The new cable was made this way:
Pins were located with ohm meter for locations and both ends were cut off.The Belden 1424A cable than was soldered to DB37 and Guralp circular connector " IKPT06F16-26S-ND "
This cable will connect the ADC interface box CCD# DO 60506 to Guralp seismometer at the sout end.
The Guralp's each 3 axies will be connected through a twisted pair to the differential input op amp
Gur ouput vertical axis + - on circular connector A, B to DB37 pin 1 &20
Gur output N/S axis + - on circular connector C, D to DB37 pin 2 & 21
Gur output E/W axis + - on circular connector E, F to DB37 pin 3 & 22
Power +12 VDC from DB37 pin 29 to Gur circular connector pin c (lower case)
Power -12 VDC from DB37 pin 24 to Gur circular connector pin M Note: this connection was absent at the first test of this cable!
Ground from DB37 pin 10 to Gur circular connector pin b (lower case)
Summery: I may destored the opamp at the Guralp A at the south end.