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Electronics => Repair => Topic started by: Dmoff on January 28, 2022, 01:47:11 pm

Title: 8920B display inop after shipping
Post by: Dmoff on January 28, 2022, 01:47:11 pm
I've got a 8920B rf comm test set that we received for cal with a inop display. replaced Crt drive board and display worked. finished cal sent back to customer. unit shows back up a week later with same problem, resat all boards and was working again. a few days go by and its back with the same problem. narrowed it down to reseating the processor board being the problem, but after looking all over the connectors and everything theres nothing that stands out. Any ideas as to what could be causing it? I dont think its coming undone as it requires quite a bit of force to get it out and we've tried to replicate shipping and unit worked just fine after. Any help is appreciated, Thank you.
Title: Re: 8920B display inop after shipping
Post by: bob91343 on January 28, 2022, 06:18:35 pm
Check solder joints and board cracks.  You need to get out the scope and DVM and make some measurements while it's not working.
Title: Re: 8920B display inop after shipping
Post by: MouldyOldGit on January 29, 2022, 09:02:52 am
Possibly you have an intermittent inter-electrode short in the CRT.