
Power Modification for External Power Source
By Kerm Martian
Kerm_Martian@yahoo.com
http://www.cemetech.tk
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Modification
| Schematics
| Placement of socket |
This modification allows you to use your calculator as both a portable device run by batteries or one powered by an external power source. It is compatible with the multiNET Docking Station for TI Calculators, available here. NOTE: Work at your own risk! I am not responsible for any errors!
Materials Needed:
- (1) Power Socket (The smaller the better!)
- (3) Pieces of Wire
- (1) Soldering Iron
Instructions
- Drill a small hole in the bottom of the calculator case 1" from the left side (when screen is facing up).
- Using a hex screwdriver or appropriate tool, remove the screws from the back of the calculator case, including the one next to the backup battery under the battery cover.
- Gently lift off the back of the case; you may need to pry it off slightly.
- Liberally apply strong glue to the bottom of the socket and place on the circuit board directly lined up with the hole you have drilled. Apply pressure until the glue has set
- Solder three wires to the socket, one to each of the contacts.
- Solder the free end of the "+" wire from the socket to the "+" contact on the circuit board. Cover it with tape; glue in place if necessary.
- Solder the wire from the switch to the "+" contact on the calculator's battery case.
- Solder the final wire to the "-" contact of the circuit board. DO NOT cover with tape.
- Before you put the cover back on, plug the power source into the socket. MAKE SURE IT IS 6 VOLTS DC!!! Turn on the calculator. It should say "Ram Cleared" and then function normally. If not, check your wiring. If the socket seems hot, you see or smell smoke, or any other sign of malfunction, disconnect the power IMMEDIATELY.
- If it works, unplug the power source, put the cover back on, and screw it back into place.
©2003 Kerm Martian