Retro Maplin "thing" (with schematic)

This falls into the category of being one of those gimmick tools that you get because it might come in handy someday. It wouldn't surprise me if it was originally one of their "special offer" things with suitable marketing hype.

It definitely has a purpose though, as it's easy to pick up and instantly do a continuity test on a fuse or lamp without messing about with dials and leads of a multimeter.

The circuitry is basic, but also quite pleasing because it uses a Darlington transistor that hints at the modern continuity testing screwdrivers that are still sold.
The Darlington transistors are a precursor to the modern super high gain MOSFETs, but inherently much more resilient to electrostatic damage.

Supporting the channel with a dollar or two on Patreon helps keep it independent of YouTube's quirks, avoids intrusive mid-video adverts, gives early access, bonus footage and regular quiet Patreon live streams.

https://www.patreon.com/bigclive

#ElectronicsCreators