Electrodex EL-64 digital diary

This is an early digital organizer and diary. It has a calendar, notes, address book and schedule. It allows to protect part of data by password. Everything is shown in large text LCD. To "scroll" entries a rotating knob is used like in some paper organizers.
The first manufacturer was Rolodex, then it was copied, cloned or licensed to different companies. My unit is made by "Zeon Tech", the software is licensed by "Tele-art".
Rolodex units had one more function: It was possible to transmit and receive data by infrared link between units. Usually one side contained transmitting and another had receiving infrared device, so two units were set properly before transfer.

Manufacturer Rolodex, later many others

Origin USA
Year of unit Early 1990s
Year of introduction Early 1990s
Type Digital diary
Battery:
 - 3 AA batteries or 4.5V DC power supply.
 - Button cell battery for memory backup
Memory: batery-backed RAM, 64kB for data.
Manual

Inside, all system internals are in display unit. Bottom part contains rotary encoder, IR LEDs, RAM backup battery and keyboard. In my unit, all ICs are only sillicon structures covered by resin, so it's not possible to perform repairs or reverse engineering.

Rolodex 32K

As a smaller version of Rolodex 64K, a 32K small unit has been introduced. It was marketed as "pocket" or "mobile" version of Rolodex 64K. Thanks to infrared transfer it is possible to exchange data with 64K version. Unlike 64K this version has no power supply socket - can be powered only by batteries.

Manufacturer Rolodex

Origin USA
Year of unit Early 1990s
Year of introduction Early 1990s
Type Digital diary
Battery:
 - 4 AA cells.
 - Button cell for backup
Manual

Unfortunately my unit has damaged LCD, so I can't see much. Its knob by default doesn't rotate full turns, but only "steps", like in some microwave ovens :). Keyboard, with its rubber keys, is not very comfortable.