burnt traces ibm model m2? (resolved)

[Touch_It]

so recently got one for free.  have just disassembled it for cleaning and it looks like some traces on the matrix are burnt.  dont have much exp in this.  but ive heard with the right pen i could redraw them.  the keyboards work but some keys didnt.  mainly  t y backspace [ and ] are the ones i can remember.  thanks in adv for replies

[DaemonRaccoon]

The M2's are known for bad capacitor problems.

EDIT: Removed misinformation.

[Touch_It]

When was your M2 made? There were membrane issues during the Lexmark transition (1993). (Not to mention the M2's bad capacitor problems.)

i guess id doesnt specificly say its an m2 but it looks exactly like one.


havnt researched it to much.

[DaemonRaccoon]

1395300? That's definitely an M2. IBM wiki has more info.

[mich]

They aren't bunt. I don't know the cause of this discoloration (because I don't know what these traces are made of) but often such brown traces still work.

Connect this board and check (by tapping the membranes with your finger) which keys don't work and whether it's correlated with discoloration of traces. The cause of this problem might as well be bad connection between the membranes and controller PCB.

[The Solutor]

They aren't bunt. I don't know the cause of this discoloration (because I don't know what these traces are made of) but often such brown traces still work.

Connect this board and check (by tapping the membranes with your finger) which keys don't work and whether it's correlated with discoloration of traces. The cause of this problem might as well be bad connection between the membranes and controller PCB.

 
+1

[ch_123]

Traces going brown doesn't mean much within of itself. If you have dead keys, you'd want to get some sort of multimeter and test the traces on which the keys are on for failure points.

When was your M2 made? There were membrane issues during the Lexmark transition (1993). (Not to mention the M2's bad capacitor problems.)

Hmm?

[Touch_It]

Traces going brown doesn't mean much within of itself. If you have dead keys, you'd want to get some sort of multimeter and test the traces on which the keys are on for failure points.



Hmm?

will do that when i get  a MM.  also teh pix dont show it but one of the traces appears to be flaking off.  

anyone know of the pen i can redraw if it is as simple as that and not a capacitor problem or the pcb isnt seated correctly.  and sadly cuz im a fool have reassembled the keyboard.  so ima have to take it apart again.

seating springs is a b**ch

[The Solutor]

If any trace is really missing, broken you should be able to repair them with a silver paint pen.

Is relatively easy to find in the car's accessory stores as, usually, is meant to repair the heater on the back window of  cars (sorry but I don't know exactly how do you call both of them)

[Touch_It]

If any trace is really missing, broken you should be able to repair them with a silver paint pen.

Is relatively easy to find in the car's accessory stores as, usually, is meant to repair the heater on the back window of  cars (sorry but I don't know exactly how do you call both of them)

ahh, thx

[Touch_It]

Going to go full necro here.  Over 3 years later pulling a Lazarus.  It'ts time to get this bad boy working.   I have verified that the only keys that are not working are:  T y [ ] backspace and on the numpad 4 5 6.  They all apear to be on the same trace.  Is this still likely a controller capacitor issue or maybe a bad trace somewhere.  (note that i did reseat the controller with no change).

[keyhopper]

Going to go full necro here.  Over 3 years later pulling a Lazarus.  It'ts time to get this bad boy working.   I have verified that the only keys that are not working are:  T y [ ] backspace and on the numpad 4 5 6.  They all apear to be on the same trace.  Is this still likely a controller capacitor issue or maybe a bad trace somewhere.  (note that i did reseat the controller with no change).

Do you have a multimeter? Select 'ohms' and test between two different points that should be connected.

They are cheap:
        http://www.amazon.com/Digital-VOLT-Meter-Voltmeter-Multimeter/dp/B005EK3NRS/ref=sr_1_5?ie=UTF8&qid=1413062806&sr=8-5&keywords=multimeter

Good luck!

Cheers!!
.KeyHopper.

[Touch_It]

Going to go full necro here.  Over 3 years later pulling a Lazarus.  It'ts time to get this bad boy working.   I have verified that the only keys that are not working are:  T y [ ] backspace and on the numpad 4 5 6.  They all apear to be on the same trace.  Is this still likely a controller capacitor issue or maybe a bad trace somewhere.  (note that i did reseat the controller with no change).

Do you have a multimeter? Select 'ohms' and test between two different points that should be connected.

They are cheap:
        http://www.amazon.com/Digital-VOLT-Meter-Voltmeter-Multimeter/dp/B005EK3NRS/ref=sr_1_5?ie=UTF8&qid=1413062806&sr=8-5&keywords=multimeter

Good luck!

Edit.  If I can find a pen that it.  Proving to be more difficult than I originally thought.

Cheers!!
.KeyHopper.

feel dumb now.  Took all of 5 minutes to find a break in the trace.  Off to a auto body place or somewhere to find a silver pen.

Thanks!

[keyhopper]

Going to go full necro here.  Over 3 years later pulling a Lazarus.  It'ts time to get this bad boy working.   I have verified that the only keys that are not working are:  T y [ ] backspace and on the numpad 4 5 6.  They all apear to be on the same trace.  Is this still likely a controller capacitor issue or maybe a bad trace somewhere.  (note that i did reseat the controller with no change).

Do you have a multimeter? Select 'ohms' and test between two different points that should be connected.

They are cheap:
        http://www.amazon.com/Digital-VOLT-Meter-Voltmeter-Multimeter/dp/B005EK3NRS/ref=sr_1_5?ie=UTF8&qid=1413062806&sr=8-5&keywords=multimeter

Good luck!

Cheers!!
.KeyHopper.

feel dumb now.  Took all of 5 minutes to find a break in the trace.  Off to a auto body place or somewhere to find a silver pen.

Thanks!

You're welcome!! I'm glad you found it!

Reparing it is easier than it seems, but do practice forming a trace on a piece of paper first.
Painted traces are usually too thick,
so you might want to "paint" by grabing a tiny droplet with a needle, box cutter tip, or tiny flat-head screwdriver.

Good luck! 
.KeyHopper.

[Touch_It]

Well typing on this as we speak.  All keys working although somewhere along the line I've lost 3 spring/hammers.  Broke a few crappy stabilizers and not all of the keys feel quite the same but its pretty cool typing on a relic.  The build date on this is actually newer than my terminal model M.   Definitely not near as well built and an absolute ***** to work with but  I will be using this as my daily driver for the foreseeable future.  On a site note, (knock on wood), I have no capacitor issues!