ZX81 and Commodore DM 602 / Philips 802 green monitor

A composite video output comes in very handy, as it allows the ZX81 to connect to many displays that were used for other home computers of the time.

Commodore DM 602 monochrome monitor, heavily used

Having an old, battered Commodore green monitor, and a ZX81 equipped with a composite video output, the two were connected.

ZX81 to monitor composite video connection

Composite video is actually a color video signal, of which only a "low" or "high" value per pixel will be used by a monochrome monitor, loosing all precision of intermediate values that represent more colors. A "low" signal pixel will be black, and a "high" one will be white, meaning green with the Commodore DM 602 monitor. The ZX81 generates only black and white, so it's a perfect fit.

ZX81 on a green screen monitor :-)

(No) surprise: It works!

ZX81 looks (just as) great on a green screen!

This monitor might be known as:

Commodore DM 602

Philips 802

Philips BM 7500

Highscreen (model name unknown)

(Is this correct? Can you add Highscreen model name? Please leave a comment.)