My old trusty (and very expensive!) meter failed on me today...
The inspection inside showed the problem lays in cracked silver tracks
on the tape connector between the keyboard and the motherboard.
Before I will go to the manufacturer and request probably
very, very expensive replacement keyboard I would like to
play with it a little and try to fix it myself...

Could you recommend some kind of conducting glue which
I could use to patch cracks in the tape conductors?

Pszemol wrote:
My old trusty (and very expensive!) meter failed on me today...
The inspection inside showed the problem lays in cracked silver tracks
on the tape connector between the keyboard and the motherboard.
Before I will go to the manufacturer and request probably
very, very expensive replacement keyboard I would like to
play with it a little and try to fix it myself...

Could you recommend some kind of conducting glue which
I could use to patch cracks in the tape conductors?

You can buy silver and nickel loaded "paint". You can paint them
across the break if you have access. Often the conductor is covered
and you can't get at it. The paint doesn't flex well...tends to flake
off.

Can you get at real circuit board on each end. I've had some success
removing the flex cable completely and soldering a zillion small wires
from end to end. But it's a one-way trip.
mike

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Return address is VALID.
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Toshiba & Compaq LiIon Batteries, Test Equipment
Honda CB-125S $800 in PDX
TEK Sampling Sweep Plugin and RM564
Tek 2465 $800, ham radio, 30pS pulser
Tektronix Concept Books, spot welding head...
http://www.geocities.com/SiliconValley/Monitor/4710/

"mike" wrote in message ...
You can buy silver and nickel loaded "paint". You can paint them
across the break if you have access. Often the conductor is covered
and you can't get at it. The paint doesn't flex well...tends to flake
off.

The connector is fed with two pieces of foil making the whole tape.
The crack is exposing metal conductors so I would be probably
able to drip some glue/paint into the crack if the paint is dense
enough to not ooze to the neighboring connection.

Is there particular name for this paint you refer to?
Where can I get it? Does RadioShack stock it?

Can you get at real circuit board on each end. I've had some success
removing the flex cable completely and soldering a zillion small wires
from end to end. But it's a one-way trip.

No, there is board on one side only.
The keyboard is a two foils, similar to well-known ZX Spectrum
keyboards - when you press the button the foil contact the crossing
conductors - the foil forms the tape with 4 conductors on each layer.
there is only 16 buttons on the device so the only hope is to fix connection.

Pszemol wrote:
"mike" wrote in message ...

You can buy silver and nickel loaded "paint". You can paint them
across the break if you have access. Often the conductor is covered
and you can't get at it. The paint doesn't flex well...tends to flake
off.


The connector is fed with two pieces of foil making the whole tape.
The crack is exposing metal conductors so I would be probably
able to drip some glue/paint into the crack if the paint is dense
enough to not ooze to the neighboring connection.

Is there particular name for this paint you refer to?
Where can I get it? Does RadioShack stock it?


Can you get at real circuit board on each end. I've had some success
removing the flex cable completely and soldering a zillion small wires
from end to end. But it's a one-way trip.


No, there is board on one side only.
The keyboard is a two foils, similar to well-known ZX Spectrum
keyboards - when you press the button the foil contact the crossing
conductors - the foil forms the tape with 4 conductors on each layer.
there is only 16 buttons on the device so the only hope is to fix connection.



The silver stuff can be had at Fry's.
GC Silver print II. 22-0023-0000
Be prepared to pay $15 for 1/2 oz of it.
Cost me $15 to fix a keyboard on a $1 laptop.

If you can't immobilize the break, it will crack right off.
mike

--
Return address is VALID.
Bunch of stuff For Sale and Wanted at the link below.
Toshiba & Compaq LiIon Batteries, Test Equipment
Honda CB-125S $800 in PDX
TEK Sampling Sweep Plugin and RM564
Tek 2465 $800, ham radio, 30pS pulser
Tektronix Concept Books, spot welding head...
http://www.geocities.com/SiliconValley/Monitor/4710/

mike wrote:
Pszemol wrote:

"mike" wrote in message
...

You can buy silver and nickel loaded "paint". You can paint them
across the break if you have access. Often the conductor is covered
and you can't get at it. The paint doesn't flex well...tends to flake
off.



The connector is fed with two pieces of foil making the whole tape.
The crack is exposing metal conductors so I would be probably
able to drip some glue/paint into the crack if the paint is dense
enough to not ooze to the neighboring connection.

Is there particular name for this paint you refer to?
Where can I get it? Does RadioShack stock it?


Can you get at real circuit board on each end. I've had some success
removing the flex cable completely and soldering a zillion small wires
from end to end. But it's a one-way trip.



No, there is board on one side only.
The keyboard is a two foils, similar to well-known ZX Spectrum
keyboards - when you press the button the foil contact the crossing
conductors - the foil forms the tape with 4 conductors on each layer.
there is only 16 buttons on the device so the only hope is to fix
connection.



The silver stuff can be had at Fry's.
GC Silver print II. 22-0023-0000
Be prepared to pay $15 for 1/2 oz of it.
Cost me $15 to fix a keyboard on a $1 laptop.

If you can't immobilize the break, it will crack right off.
mike

It may be that you are describing the same paint often used for
repairing the rear window defogger traces on automobiles? If not, I
have read of people repairing such traces on circuits by using that kind
of paint. It is available in auto parts stores.

wrote in message ...
It may be that you are describing the same paint often used for
repairing the rear window defogger traces on automobiles? If not, I
have read of people repairing such traces on circuits by using that kind
of paint. It is available in auto parts stores.

WOW! What a great idea... Is it flexible after curing or will it crack?

Pszemol wrote:

wrote in message ...

It may be that you are describing the same paint often used for
repairing the rear window defogger traces on automobiles? If not, I
have read of people repairing such traces on circuits by using that kind
of paint. It is available in auto parts stores.


WOW! What a great idea... Is it flexible after curing or will it crack?

I have never used it, but I believe it is neither flexible nor totally
rigid. There is SOME flexibility, but it would be limited.

"Pszemol" schreef in bericht
...
"mike" wrote in message
...
You can buy silver and nickel loaded "paint". You can paint them
across the break if you have access. Often the conductor is covered
and you can't get at it. The paint doesn't flex well...tends to flake
off.

The connector is fed with two pieces of foil making the whole tape.
The crack is exposing metal conductors so I would be probably
able to drip some glue/paint into the crack if the paint is dense
enough to not ooze to the neighboring connection.

Is there particular name for this paint you refer to?
Where can I get it? Does RadioShack stock it?

Can you get at real circuit board on each end. I've had some success
removing the flex cable completely and soldering a zillion small wires
from end to end. But it's a one-way trip.

No, there is board on one side only.
The keyboard is a two foils, similar to well-known ZX Spectrum
keyboards - when you press the button the foil contact the crossing
conductors - the foil forms the tape with 4 conductors on each layer.
there is only 16 buttons on the device so the only hope is to fix
connection.



I ever used roadrunner wire to fix a brown foil. The lacquer could be
scratched from the copper traces and I could use ordinary solder to connect
the wire to the traces. I guess you cannot solder those aluminium traces on
that clear foils. So you can use the conducting glue that is meant to repair
rear window heaters in motorcars. If you try to repair the cracked traces
without wire, they may crack again the first time they're bended.

petrus


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