BLE serial hub to WiFi and Blynk visualisation app

So that I can continuously post environmental data to the Blynk cloud service from my Bluetooth environmental monitor, I’ve implemented a simple design using a Keyes HM-10 Bluetooth 4.0 module and a Wemos D1 mini WiFi device as a Bluetooth hub and internet gateway. If you are not familiar with the Wemos D1 Mini. It’s Read more about BLE serial hub to WiFi and Blynk visualisation app[…]

Obtaining a UK Amateur Radio License – Racing down the M6 heading for the M0

There are two areas of electronics which really teach you what you need to know about pure analogue electronics. They are Audio and Radio Frequency design. To do both you need a good grounding in all the basics and a good feel for how they tie together. I’ve been an electronic design engineer for a Read more about Obtaining a UK Amateur Radio License – Racing down the M6 heading for the M0[…]

Digital multimeter calibration for voltage, resistance and current

I got a little carried away with this one! I have an old multi-meter whose calibration was unknown. Surely an accurate voltage reference would help with that. After spending somewhere around £80.00 designing and building a calibrator for my cheapo old multi-meter i feel I’ve given this project more than it needed:-)     There Read more about Digital multimeter calibration for voltage, resistance and current[…]

LED lamp dimmer with a 555 timer and comparator

I wanted a simple bedside lamp with a continuously variable brightness. Something I could read from whilst also being able to dim the lamp in an analogue manner to a level where it could be left turned on over night so that I could see the baby but not wake him in his Moses basket. Read more about LED lamp dimmer with a 555 timer and comparator[…]