Budget bench supply

I wanted a more portable bench power supply than my bench power supply, that I could just quickly plug into a project to test without having to find banana plugs etc. I originally thought I'd have screw terminals as output but decided just a couple of loose wires (or JST plugs) were more flexible.

In fact this power supply is more flexible than my bench supply - it does about 4v to 28v at 2A from a single 18650 Li-Ion battery that is chargeable via USB - no mains supply required. You could skip the 18650 battery and just use a single cell lipo.

[TP4056](https://www.aliexpress.com/item/New-1Pcs-lot-5V-1A-Micro-USB-18650-Lithium-Battery-Charging-Board-Charger-Module-Protection-Dual/32631921696.html)

[Voltmeter](https://www.aliexpress.com/item/1pc-0-36-Professional-LCD-digital-voltmeter-4-5-30V-voltimetro-Red-LED-Amp-Volt-Meter/32722949651.html)

[JST cables](https://www.aliexpress.com/item/10-Pairs-150mm-JST-Connector-Plug-Cable-Male-Female-for-RC-Battery/32716500577.html)