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Electronics => Repair => Topic started by: JohnPi on December 29, 2017, 11:32:05 pm

Title: Symmetricom X72 Serial Port Fried
Post by: JohnPi on December 29, 2017, 11:32:05 pm

I accidentally touched the Tx and/or Rx pins of my X72 to the +23 V supply I was using -- the Tx output is stuck at +23 V now. The rest of the oscillator works (and I can use the EFC to adjust the frequency), but now my project to use a Teensy to control the system is on hold.

Does anyone have pics of the PCB inside ? Are those components likely repairable ? It's likely some TTL-type of buffer, but I haven't opened the case yet.

Title: Re: Symmetricom X72 Serial Port Fried
Post by: coromonadalix on December 30, 2017, 04:46:43 am

http://www.rdrelectronics.com/skip/nov/X72.pdf (http://www.rdrelectronics.com/skip/nov/X72.pdf)
http://www1.symmetricom.com/media/files/support/productmanual/man-x72.pdf (http://www1.symmetricom.com/media/files/support/productmanual/man-x72.pdf)

may help a little if you dont have them already

http://webmaail.ko4bb.com/getsimple/index.php?id=manuals&dir=06_Misc_Test_Equipment/Symmetricom (http://webmaail.ko4bb.com/getsimple/index.php?id=manuals&dir=06_Misc_Test_Equipment/Symmetricom)    some pictures ...

Normally you should have some buffers / transceiver chip(s)  try to find their number once the case is opened ...  no service manual found while ggolgling ...