Repair infrared soldered connection?

[Ken]

I have a cordless phone with a LCD that has some of the characters
missing. I was able to determine it is a poor connection at the point
which a flex ribbon cable is attached to the PWB. That connection is
apparently soldered with the infrared technique. Does anyone have any
ideas on how such a connection could be repaired with common electronic
repair tools?

Obviously it can be done with the tools used to assemble the circuit
when made, but not many people have such tools in their homes. Thanks.

 

[JANA]

You need the proper tools. Call Sony or one of their service centres and see
if they will do it for you. It is very possible that they only buy and
replace the parts only.

--

JANA
_____


I have a cordless phone with a LCD that has some of the characters
missing. I was able to determine it is a poor connection at the point
which a flex ribbon cable is attached to the PWB. That connection is
apparently soldered with the infrared technique. Does anyone have any
ideas on how such a connection could be repaired with common electronic
repair tools?

Obviously it can be done with the tools used to assemble the circuit
when made, but not many people have such tools in their homes. Thanks.

 

[N Cook]

I have a cordless phone with a LCD that has some of the characters
missing. I was able to determine it is a poor connection at the point
which a flex ribbon cable is attached to the PWB. That connection is
apparently soldered with the infrared technique. Does anyone have any
ideas on how such a connection could be repaired with common electronic
repair tools?

Obviously it can be done with the tools used to assemble the circuit
when made, but not many people have such tools in their homes. Thanks.

Can you bodge something in the way of mechanically compressing the contacts
using wrap-around cable tie/s and "folding wedges" from wooden clothes pegs
?

 

[Sam Goldwasser]

Can you bodge something in the way of mechanically compressing the contacts
using wrap-around cable tie/s and "folding wedges" from wooden clothes pegs
?

Or, I was going to suggest silver (conductive) Epoxy.

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[Ken]

Can you bodge something in the way of mechanically compressing the contacts
using wrap-around cable tie/s and "folding wedges" from wooden clothes pegs
?

We must have gone to the same school. I wedged into the area of the
connection a piece of hard rubber that will press against the area when
the phone is closed. It is working, but I wish there was a permanent
fix. With so many on this newsgroup fixing so many things, I thought I
would ask if anyone had fixed such a connection. Thanks for the reply.

 

[Ken]

Or, I was going to suggest silver (conductive) Epoxy.

Conductive epoxy? Do you have a brand or type you have used?

 

[Andy Cuffe]

We must have gone to the same school. I wedged into the area of the
connection a piece of hard rubber that will press against the area when
the phone is closed. It is working, but I wish there was a permanent
fix. With so many on this newsgroup fixing so many things, I thought I
would ask if anyone had fixed such a connection. Thanks for the reply.

This is one of those cases where they had trouble making good
connections under ideal factory conditions, so doing better at home is
unlikely. I hate this design because it's basically non-serviceable.
I've had some luck heating the area that has the bad connection by
pressing a soldering iron against it. You have to be careful that the
tip isn't hot enough to melt the plastic (use a variable temperature
soldering iron). Even after that, installing something to apply
constant pressure is a good idea.
Andy Cuffe

[email protected]

 

[William Sommerwerck]

I'm a bit unclear about this. LCDs are often connected to the PCB with a
conductive-rubber band. It seems odd that one would be soldered in.

 

[Ken]

I'm a bit unclear about this. LCDs are often connected to the PCB with a
conductive-rubber band. It seems odd that one would be soldered in.

This one uses a flex cable of the ribbon type. It appears that the
conductors are soldered with solder paste using the IR heating
technique. The problem in heating the connection again is the plastic
the conductor is mounted on will be damaged unless you use a low temp
iron or the original IR process of heating the solder paste during assembly.