Upgrading to a “Real” Keyboard: E-Z Key Makes It Easy

Back in the September ’85 issue of SUM, we ran an article on adding a large size keyboard to your computer. I find it necessary to bring it up again for this special issue.

A fullsized keyboard makes all the difference in the world and E-Z Key has made it easy to build your own keyboard interface for the ZX80/81, TS1000/1500/2068.

E-Z Key will supply the printed circuit board for $9.95 + $1.95 postage & handling. To get the circuit board and their most recent catalog, write to: E-Z Key, 711 Southern Artery, Quincy, MA 02169; (617) 773-1187.

The printed circuit board has plated thru holes and feed thru connector. This is the same interface that is used in their famous E-Z Key 60 keyboard. The edge connector is not included but can be purchased from Zebra Systems found locally.

The circuit is very similar to the one that appeared last September. When installing the parts, be sure that the parts are aligned up correctly and keep the wiring to the keyboard as short as possible. Less than 18 inches. I have found that if you use ribbon cable, use every other wire for the data lines and ground the ones in-between. This will help cut down on key errors.

The connection to the keyboard can be done through direct wiring from where it says J1 on the circuit board, or a 15 pin single inline plug (SIP) can be used. Follow the board layout closely. The notch for the feedthru connector needs to be cut. The place to cut is the sixth finger from the center of the board. Make sure that the key on the computer side of the interface also aligns with the sixth finger. These extra fingers are there for 2068 use also. Make sure the computer is unplugged while making any connections.

Once assembled, check for any loose wires, solder bridges or bad connections. Plug the interface in and turn on the computer to try it out. If any keys pressed gives something other than what it should be, turn off the computer and check again. You can add extra dedicated keys by the supplied schematic or the one shown in the September ’85 issue.

This interface will work on all Sinclair computers (except the QL). And will greatly enhance the use of your computer. A completly assembled unit is also available from E-Z Key.