my recent reads..

LEAP#330 Any-to-any Polarity DC Power Adapter

I recently got a device that has a 2.1mm power connector but in centre-negative configuration. Unfortunately I don’t have any centre-negative power packs on hand. I could of course just rewire one, but decided it might be the time to make up a generic any-to-any connector. In addition to centre-positive and centre-negative output plugs, I included a 9V battery bypass and polarity rectifier, so that the input supports both centre-positive and centre-negative connections. And of course an LED power indicator. As always, all notes, schematics and code are in the Little Electronics & Arduino Projects repo on GitHub hero_image


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LEAP#329 On DC Power Connectors

How many types of power connector is there? In addition to just two bits of wire twisted together, it is pretty much an uncountable selection! Just some notes on the main types, including bypass configurations. As always, all notes are in the Little Electronics & Arduino Projects repo on GitHub hero_image


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LEAP#328 555 Timer VCO

The control terminal of the 555 timer can be used to adjust the upper and lower thresholds with an applied voltage. This produces a very simple voltage-controlled oscillator. The few measurements I’ve taken show that control adjustments have as much impact on duty cycle as frequency. That may be what you want … or not! As always, all notes, schematics and code are in the Little Electronics & Arduino Projects repo on GitHub hero_image


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LEAP#327 Diode Ring Mixer

A DIY build of a double-balanced diode ring frequency mixer, inspired by another video from w2aew and the endless treasure-trove that is Experimental Methods in RF Design. As always, all notes, schematics and code are in the Little Electronics & Arduino Projects repo on GitHub hero_image


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