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IanM[_4_]

hr(bob) wrote:
On Jan 2, 3:47 am, IanM wrote:
Francis McGrath wrote:
On Jan 1, 10:46 pm, "hr(bob) "
wrote:
On Jan 1, 10:38 pm, Francis McGrath wrote:
I have a flat ribbon cable in a synthesizer that senses pressure
aftertouch. It lets you play a note, then push harder on the key to
get an extra effect. Well, I put a screw through it. I'd like to
repair it because it's easy to get to the hole, but really hard to
remove the whole cable. The problem is that I don't know what kind of
wire it is or how it works. Since I don't know what it's called, it's
hard to do a google search. I've posted a picture of it athttp://www.francismcgrath.com/wire.jpg. Can someone tell me what this
kind of wire is called? Secondly, I'd be very interested in learning
how to fix it.
Thanks, Francis
How many conductors are there in the cable, and do you know how to
solder?
Thanks for posting.
There are 2 wires that come out of the blue connector, so I guess that
means 2 conductors. That's part of what makes me confused, there only
appears to be one cable zig-zagging through the wire, but on closer
examination, the zig-zagging part is clear. And yes I can solder.
Francis
It looks like some sort of capacitive sensor. I don't think the QTC type
of pressure sensor can be made clear like that. You have lost three of
the 'fingers' but there is no damage to the main conductors. Also from
the diagonal crease, the damage would appear to be between the keyboard
and the circuit board, *NOT* under any keys.

YOU GOT LUCKY!

Just take a very sharp craft knife and trim the edges of the hole
carefully taking off as little as possible to remove any fragments that
might short-circuit, but *DO* *NOT* nick or cut the main conductors top
and bottom. It should still work just fine. If the crease is your
doing, and the hole is under a key try it anyway but it may need to be
adjusted sideways slightly so the hole falls between keys. If the hole
is in contact with any metal surface when installed put a bit of
insulating tape on the metal to prevent contact (not on the hole, the
'sticky' may cause problems when it ages).

--
Ian Malcolm. London, ENGLAND. (NEWSGROUP REPLY PREFERRED)
ianm[at]the[dash]malcolms[dot]freeserve[dot]co[dot]uk
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But if the hole cut thru any of the conductors, like it appears to do,
the OP will have to reestablish continuity by soldering a wire to each
end of the broken path to reestablish the continuity.

The OP stated (*EMPHASIS* added by me):
appears to be one cable zig-zagging through the wire, but on closer
examination, the zig-zagging part is *CLEAR*. And yes I can solder.

The zigzag is clear and is extremely unlikely to be a conductor. There
are two contacts described at the blue end. I therefore concluded the
white/silver strips with interlocking fingers were the conductors, which
would suit capacitive proximity sensing. *NOTHING* will need bridging
and soldering that sort of cable *will* destroy it unless the OP has an
extremely delicate touch.

--
Ian Malcolm. London, ENGLAND. (NEWSGROUP REPLY PREFERRED)
ianm[at]the[dash]malcolms[dot]freeserve[dot]co[dot]uk
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