DMD fault- non fault

Debbieneon

Member
Oct 21, 2017
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Derbyshire
hi all- i have a DMD on a frankenstein that threw a line out some months back-the fault never changed,the same as my WW that still begs for a new DMD when i get round to it....the thing is the display went completely black so i thought it was shot....until i took the DMD off the pin and checked all the plugs and re seated the 5v power plug...which is pretty loose ...powered up again and the line was no more!! switched on and off several times and all was good?? and still is..am i wrong to think that once a DMD has a line out it stays out..how the .... can it make good again? thanks Adam
 

pinballmania

Well-Known Member
Jul 21, 2011
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Lines are normally out because the electrical connection is physically broken.

On standard dmds it’s normally a broken contact where the conductor enters the glass sandwich. It’s also normally at one edge. It’s hard to resolder as there’s not enough surface area to make a connection to on the glass. But you can make a repair with a blob of conductive epoxy.

On super sized dmds the connections are often by way of adhesive ribbon cable. This can cause connectivity problems anywhere along the ribbon. Applying pressure to the affected area can reestablish connection.

Whilst moving the display you may have remade the electrical connection sufficiently to reestablish the line.
 
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pinballmania

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Jul 21, 2011
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I think neon is referring to the adhesive Ribbon to the dmd glass. I don’t know of any technique to permanently repair.
 
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Debbieneon

Member
Oct 21, 2017
97
10
8
Derbyshire
ok... maybe it will hold out for now..thought it was a lack of volts from the crappy 5v plug...and maybe a weak joint on the ribbon...going to fit a new plug and see what happens :thumbs: