The perfect keyboard with lots of keys - can be labeled...
bill190
Posts: 769
I'm working on an IR remote project and need lots of keys on a keypad which I can easily label.
Existing remote control keypads don't have the keys I need and I can't stick labels on them because the keys are squished in too tight.
Same problem with a computer keyboard, can't label keys. And a bit big for a remote control.
And new keypads don't have enough keys or you can't easily label them.
But I found the perfect solution... An old phone!
It has 22 buttons, many of which are spaced out, so I can tape labels by them. Plus there is a 9volt battery compartment. LED lights. And a speaker!
Then only 50 cents at a 2nd hand store.
What more could a guy want?
I'm looking at different options now. One is capacitive touch. With that in theory you can have copper pads, then place a printed piece of paper over the pads which identifies each key. Then place glass or Plexiglas over that. Placing your finger over a copper pad area activates the capacitive touch sensor. (Your finger acts as a capacitor added in parallel to the circuit.)
Here is a thread on that...
http://forums.parallax.com/showthread.php?t=117718&highlight=capacitive+touch
Existing remote control keypads don't have the keys I need and I can't stick labels on them because the keys are squished in too tight.
Same problem with a computer keyboard, can't label keys. And a bit big for a remote control.
And new keypads don't have enough keys or you can't easily label them.
But I found the perfect solution... An old phone!
It has 22 buttons, many of which are spaced out, so I can tape labels by them. Plus there is a 9volt battery compartment. LED lights. And a speaker!
Then only 50 cents at a 2nd hand store.
What more could a guy want?
I'm looking at different options now. One is capacitive touch. With that in theory you can have copper pads, then place a printed piece of paper over the pads which identifies each key. Then place glass or Plexiglas over that. Placing your finger over a copper pad area activates the capacitive touch sensor. (Your finger acts as a capacitor added in parallel to the circuit.)
Here is a thread on that...
http://forums.parallax.com/showthread.php?t=117718&highlight=capacitive+touch
765 x 1135 - 103K
Comments
http://actionelectronicswholesale.com/Conductive-Paint-C324.aspx
I wonder if I could paint capacitive touch sensor pads on a wall, paint the connections to each going down the wall to wires, then paint over all that with regular house paint and have hidden touch sensors in the wall?
That might be prone to Electromagnetic Interference, so maybe place a grounded screen on the other side of the drywall (inside the wall). Perhaps use shielded coax to each touch sensor?
Another problem I've read about is "parasitic capacitance" where you run the touch sensor's connecting wires too close to each other or too close to a ground trace/wire. Spacing the ground shield on the other side of the drywall (1/2 inch) would give plenty of space I imagine?
Another idea is a "remote control coffee table". Use capacitive touch sensors, a printed piece of paper over that to identify each key, then glass or Plexiglas over that...