Telex KP-12 Display Drivers or bad solder?

[Austel91]

We have about 4 - 5 Telex KP-12 Panels that we use on a regular basis that have a display problems. The display for the local menu is supposed to have 8 dashes across it so you know the display is on and functioning. At random times half the display will go out (so only four dashes appear). Anyone that has used this panel knows that these dashes turn into lettering of menu options like "DISPLAY" or "SERVICE." However since half the display isn't lighting up I can't read these menus and access them. I know that the menu options are functional because I can still make changes to the panel locally; but I have no idea what I'm changing because I can't see the fully display, only half of words or sometimes none of the words. I was told this was a either an display driver problem, or a cheap environmentally safe solder that was used in these panels that and has been known to cause problems. I'm not wanting to send in 5 panels to the shop for a repair that I can do. If it is a cheap solder I can fix it easily, but if it is a driver problem I can't update it without sending it in to get a new driver card. Any thoughts?

 

[cpf]

Is it truly random? If it works for a period of time after you start the unit, then fails, I'd put my money on a poor solder joint and thermal expansion.

Regardless, if you're comfortable taking stuff apart and using a soldering iron, resoldering the appropriate connections would be a relatively quick thing to try, and if it doesn't fix it, you know that wasn't the problem.

 

[Austel91]

On the panels that are truly random I am going to take another look at it and see if I can create the problem. The ones that fail at a certain point I will probably open it up and solder it again. your right it would be a good test.

 

[Call911]

If I can ask a side question, I've seen these units before I'm huge professional stadiums and convention halls, but what purpose do they have in a theater setting?

 

[Austel91]

It is being used in a HD Trailer. They might be over board but we have panels placed throughout our shooting facility. They are used in both large and small shoots; seeing as the trailer is never right next to the stage it makes it easier to get a hold of the person you actually want to talk to (instead of Party Lines or SL). Just like any other large facility that needs to communicate to a trailer. We have about 3,000-4,000 people a week in this facility.