Uploaded August 2026 | Updated September 2026, 2 weeks ago
This device detects dusk and only turns a light or other load on for a fixed time if it hears a noise. That could be useful as a security device, as an alternative to a PIR sensor.
The circuitry is notable for using a common technique for switching medium loads with very low control current. But that does limit the power it can switch.
This circuit has lots of interesting quirks. From the load switching to the use of the chip's internal pull up resistor as part of the dusk sensing voltage divider.
These have been around a long time, so they're probably available from all the usual online marketplaces. Here's an affiliate link to where I bought this one from:-
https://s.click.aliexpress.com/e/_c4EzVlgX
If you add it to your basket it may appear as a bundle deal. It should cost £2 or less.
If you enjoy my videos, supporting the channel 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.
patreon.com/bigclive
Alternatively, for a single coffee contribution you can use PayPal:-
paypal.com/paypalme/bigclive
#ElectronicsCreators
This device detects dusk and only turns a light or other load on for a fixed time if it hears a noise. That could be useful as a security device, as an alternative to a PIR sensor.
The circuitry is notable for using a common technique for switching medium loads with very low control current. But that does limit the power it can switch.
This circuit has lots of interesting quirks. From the load switching to the use of the chip's internal pull up resistor as part of the dusk sensing voltage divider.
These have been around a long time, so they're probably available from all the usual online marketplaces. Here's an affiliate link to where I bought this one from:-
https://s.click.aliexpress.com/e/_c4EzVlgX
If you add it to your basket it may appear as a bundle deal. It should cost £2 or less.
If you enjoy my videos, supporting the channel 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.
patreon.com/bigclive
Alternatively, for a single coffee contribution you can use PayPal:-
paypal.com/paypalme/bigclive
#ElectronicsCreators
