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Products => Test Equipment => Topic started by: charlyd on November 07, 2017, 11:06:47 pm

Title: Tektronix TDS784D Input Channel 4 Failure
Post by: charlyd on November 07, 2017, 11:06:47 pm
Hello I got a TDS784D with input failures on all inputs with a trigger constants error on channel 4.
i didn t  get any triggered signal in the beginning so i took out the ACQ board to get to the Attentuators.
From what i saw i had 3x H2462J and 1x H2462H the last one was installed on CH 2.
i ordered some sets relays to refurbish all my attentuators. and ordered a  H2462J version because i want 4 of the same Hybrid plates in the scope.
Replaced the relays  and putted back in all the hybrids the New J version didn t arrive yet so i refurbished all 4 hybrids which came out  ( 3xJ +1xH) and putted them back in scope to see what happened.
the respons was much better:
Ch 1 -> looks OK at first site!
Ch 2 -> looks OK at first site!
Ch 3 -> looks OK at first site!?!   
Ch 4 -> just a blue line nothing happens. ( with H2462H which should be downwards compatible from what i found on the web)
When the New J version arrived and placed inside, i quickly found out the relays also had to be replaced. those relays were clicked randomly on the just arrived J version. So i ordered an extra 4 relays which will arrive in a few days after i tested with all  refurbished J versions later i will give an update here.... 

Any suggestion yet why channel 4 is giving NO response?
know issue for anybody who had this problem ?

Title: Re: Tektronix TDS784D Input Channel 4 Failure
Post by: DC1MC on December 10, 2018, 06:48:29 pm
Hi, do you happen to have the H2462H available anymore ?

 Cheers,
 DC1MC