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View Full Version : Thinking of offering a dmd repair service.



phreak97
19th May 2013, 09:13 PM
I have a technical background and I know replacement displays are $200+
I can repair scrambled sections and stuck lines. Basically anything except problems with the actual tube.

Is there much demand for this?
For those interested, what sort of pricing would you want to pay for repairs like these?

This is inspired by an ic replacement I just did on my own dmd to fix a vertical line which was stuck on:)

kirk332
19th May 2013, 11:49 PM
Share the love and teach us how and keep the hobby alive! Post your fix in Pinwiki for the world to see! Other wise I guess I'd pay around $50 for a guaranteed repair, mind you I would do a lot of my own fault finding before I would send it off to anyone.

Homepin
20th May 2013, 02:20 AM
Great idea but postage at $15 each way would hurt...:unsure

phreak97
20th May 2013, 08:09 AM
Theres really not much to it, it's either broken traces or one of the driver ics.
If its horizontal lines its probably the horizontal driver ic, if its vertical follow the traces back to the ic to find out which one it is.

The difficulty is in desoldering the old chip and soldering the new one, theyre all surface mount with pins on four sides.

Even if it's just a local service I dont mind, I just thought I'd put the idea out there:) I was thinking $50 each too

Darksoul
20th May 2013, 08:42 AM
Great offer, even if it is only for local Adelaideans

sleazius
20th May 2013, 12:01 PM
I'm sure at $50 you'd get interest. There are people who like to keep their machines as original as possible who would gladly pay to keep their DMDs alive.

phreak97
20th May 2013, 01:38 PM
Lets give it a go then, anyone got any to be fixed?

WOKA
20th May 2013, 02:11 PM
How about an exchange service offering next day turn around..?

You have a repaired one on hand, I send you my failed one, you send out a fixed one, repair my failed one and put it back into stock.

phreak97
20th May 2013, 02:17 PM
I like the idea but I'll end up stuck with a blown tube if I do that. We'll see how many Irreparables I get first.
Also no fix no fee.
If I have the parts in stock itll be an hour turnaround anyway.

WOKA
20th May 2013, 02:23 PM
I suppose you have to factor in the 'fail to fix' rate and price that into the service accordingly.. But I understand where your coming from.

Though its similiar to your 'no fix - no fee' service.. It takes time and time is money to diagnose to the stage where you determine its irrepairable. Say, one in 20 non repairable v's time to determine if they are indeed repairable. Where's your time (money) better spent..?

GIBO
20th May 2013, 02:26 PM
What's your success rate at fixing missing lines as this is a more common problem than stuck on lines

phreak97
20th May 2013, 02:30 PM
Most of the irrepairables would be easy to spot based on what displays onscreen. I'm happy enough to do exchanges on dmds with scrambled images (assuming I can get a spare one) because I know those are repairable, ones with other issues are more case by case basis.

I understand where youre coming from with the flat rate exchange and just factoring dead ones into the price, and it could be viable but I'll need a couple of spare dmds before I can start that.

For now I'll have to repair yours and send it back.

phreak97
20th May 2013, 02:33 PM
Missing lines are one of those problems that need to be attempted before knowing if it will be successful. Most of the time it seems to be the ribbon whih is easy to bypass but if the line is cracked inside the glass it's not really repairable. The glass can be ground away a bit but its risky.

gottaconnect
20th May 2013, 03:49 PM
I think its a great service.
Anytime someone cant fix something themselves, its good to know someone else can.
I would gladly pay.

Fish Tales
20th May 2013, 04:09 PM
I have a spare one, missing 2 lines that will need the glass ground away, prob worth a shot as it is nice and bright.

Mr Pubstuff
20th May 2013, 06:35 PM
i got one htat i noticed last week has 1 or 2 missing lines at the top. the rest is nice and bright, i'd probably be interested in seeing if it can be bought back altho im not sure if this is the one i had that another AA'er who knew less than he thought he did has already had a go at...

phreak97
21st May 2013, 08:46 PM
I'm happy to give those a go but any glass grinding can potentially destroy the display. I am more than happy to take responsibility for damage during pcb repairs, but if a glass grind is unsuccessful I dont want to be replacing the display.
Does that sound fair?
I'd of course confirm that the glass tube is in fact at fault then contact you about the risk on a case by case basis.

It's possible some missing lines are wrongfully diagnosed when the actual problem is a driver output stuck low. An easy way to test that is to disconnect the resistor on the affected line, disconnect the one next to it, then wire that one into the affected line instead. If the line starts doing something it's a bad ic or problem on the pcb

furballx
22nd May 2013, 01:49 PM
Also, missing lines due to broken pins are usually due to the breakage being at the glass interface. Melting the solder at the board under that pin will generally cause the pin to fall out if it is cracked there. I reckon it is quite OK to offer the glass grinding as repair without warranty "all care no responsibility". It is a risky repair, & by the time you get there it is usually an all or nothing situation anyway.
Dave

phreak97
24th May 2013, 09:34 PM
Just successfully repaired two dmds, one showed solid orange with a few missing lines, the other was just missing lines. I scraped the material between the glass layers back then used a silver oxide pen to glue the pins back. Seems to be working well