CMU 200 pinout of DIGI BOARD please - Page 1
Forum section: electronics / testgear

author: om4ik
author_rank: Contributor
timestamp: October 18, 2020, 09:15:22 am
content: Hallois there anybody who has full service manual with schematic of CMU 200 or has some schematic ? I need pinout of DIGI BOARD please. If anybody is able to make screenshot or photo of pinout (5 connectors) it will be very helpful for me. i think it is on mainboard diagram and the name of connectors are X71 X72 X73 X74 X75Very THANX

author: Qw3rtzuiop
author_rank: Frequent Contributor
timestamp: October 18, 2020, 11:10:21 am
content: Here are the connector descriptions for the DIG board. I cant upload all because of the file size limit. But i will submit it to xdevs.com/docs.

author: om4ik
author_rank: Contributor
timestamp: October 18, 2020, 12:05:33 pm
content: Hithanx very much for your reply my friend. Now I know the problem is on signal called "diagnose" (X72:B2) but not on mainboard but somewhere in Digiboard. Have you got also schematic of this board please ?Thanx for your time

author: Qw3rtzuiop
author_rank: Frequent Contributor
timestamp: October 18, 2020, 12:10:05 pm
content: Nope unfortunately not.I think those schematics weren't published.

author: om4ik
author_rank: Contributor
timestamp: October 18, 2020, 05:14:26 pm
content: So I measure all the day and I hope the problem is really on DIGI board. CMU200 cant measure any selftest diagnostic parameters (all measuring are INVALID) so I look at the schematic (thanx Qw3rtzuiop) and every board has parallel conected via 100R rezistor diagnose signal and this signals going to DIGI board for AD cnversion. DIGI board has also selftest diagnostic but this signal is internally conected with all other external signals from other boards to electronic IC switch DG419 which is electronic switcher with 2 inputs and 1 output so this switch probably switching between DIGI board diagnose signal and others boards diagnose signals and it looks like it switching it to AD converter. I measure on this IC and there is a short circuit between internal diagnose input to switcher output and also this pins are also short circuit to GND. I hope the problem is on this switch so I desolder it but switch is OK and short circuit is also there. i think this is reason why selftest not pass and take invalid parameters on all measure values. I havent got circuit diagram of this board so I dont know where is this short circuit it is very dificult to measure because it is short circuit to GND and without schematic or another board it is problem. I want to ask someone if is it possible can you try to measure with ohmmeter this pins on your board please ? In my there is absolutly short circuit 0.0 ohm. It is pin n.1 ad pin n.8 between GND (chasis of board). I attached a photo where is switch situated. It is under the small board (1100.3220) so it must be take away from the DIGI board. under this board is situated switch (see photo 2). Maybe somebody has DIGI board like a spare part or faulty with another problem like mine so if you can measure it will be very helpful for me.Thanx

author: om4ik
author_rank: Contributor
timestamp: October 19, 2020, 08:15:55 pm
content: HiNow I find burned 3 pin component. There is a little dot on center of package and it is unreadable (SMD code) so I dont know if it is diode or tranzistor etc). This component is conected to A/D converter to pin for analog positive voltage so it is maybe transistor. Can someone look on your board on this component what SMD code is on it please ? (I read only 20 and something unreadable). I attach a photo where it is situated.Thanx