For years, Game&Watch collectors have been puzzling of what is known as the "cardiogram" logo. The logo is imprinted on a Fire of the Wide Screen series. It’s clear, that the game comes from Great Britain because it carries the CGL logo. So it was suspected that the company with the cardiogram logo should also come from England.

Old Cockpit Panel from a RAF (Royal Air Force) Tornado FighterNow the secret is revealed: It’s the company Plessey from the UK. Plessey was a British, international electronics, defense and telecommunications company founded in 1917. In 1989, it was acquired by a consortium of GEC and Siemens, which split the assets of the Plessey Group.
Quelle und weitere Infos: Wiki

Many thanks to Peter, Aris and Norman for the great hints!

PS: In the Promo FAQ, the Fire is no longer listed as a "cardiogram", but correctly as "Plessey" :)