CRT 7900 Display fault/schematic..

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Raverrst
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CRT 7900 Display fault/schematic..

Post by Raverrst »

As in title, Iv a Crt 7900 with a couple of segments of the LCD not lighting up, so (Fm/Am) aren’t being displayed properly in the display. Anyone had this fault before? Or can someone point me to a schematic for the CRT 7900 or the Anytone 5555n..

Many thxs guys n girls..
☢️Wednesday’s and Sunday’s 9pm 27.405 Usb, Qsk’s welcome☢️
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ch25
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Re: CRT 7900 Display fault/schematic..

Post by ch25 »

Bad contact on LCD elastomer.
You need to disassemble, and clean.
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Raverrst
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Re: CRT 7900 Display fault/schematic..

Post by Raverrst »

Thanks for the reply ch25, Yes I’m thinking that could well be the fault, Job for the wkend ..
☢️Wednesday’s and Sunday’s 9pm 27.405 Usb, Qsk’s welcome☢️
Edd200sx
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Re: CRT 7900 Display fault/schematic..

Post by Edd200sx »

Ate strip and clean with some ipa had the same on a 9900
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Raverrst
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Re: CRT 7900 Display fault/schematic..

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Thanks, sounds like that could well be the fault then 🤞
☢️Wednesday’s and Sunday’s 9pm 27.405 Usb, Qsk’s welcome☢️
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Re: CRT 7900 Display fault/schematic..

Post by Edd200sx »

Just take care stripping it apart as it’s easy to break something
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Raverrst
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Re: CRT 7900 Display fault/schematic..

Post by Raverrst »

Right, striped the LCD out of the metal cage to gain access to the elastomer, it seems like the side fitted to the LCD glass itself is stuck on? Would this be right? Didn’t want to apply to much pressure for fear of causing damage. Cleaned the accessible side and the board pads, however the fault is still present. Iv given the board a good look over through a magnifier and all looks fine no damage etc.. Any thoughts guys.. Thxs
☢️Wednesday’s and Sunday’s 9pm 27.405 Usb, Qsk’s welcome☢️
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Re: CRT 7900 Display fault/schematic..

Post by Edd200sx »

Raverrst wrote: 05 Mar 2022, 19:50 Right, striped the LCD out of the metal cage to gain access to the elastomer, it seems like the side fitted to the LCD glass itself is stuck on? Would this be right? Didn’t want to apply to much pressure for fear of causing damage. Cleaned the accessible side and the board pads, however the fault is still present. Iv given the board a good look over through a magnifier and all looks fine no damage etc.. Any thoughts guys.. Thxs
Aye they can appear stuck on but will peel off
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Raverrst
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Re: CRT 7900 Display fault/schematic..

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Thanks, Yes iv managed to remove, so cleaned both sides and the glass contacts, fault still remains, I did note that there was a slight depression on the top side of the rubber strip, not on the contacts tho, unsure if that would cause a problem? As said iv had a look at the board itself through a magnifier can’t see any track damage etc?
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Edd200sx
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Re: CRT 7900 Display fault/schematic..

Post by Edd200sx »

Maybe the lcd is faulty then. Pretty sure Doug at knights
Can get them. Hard to say without seeing it.
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