I bought a CP-10 to see if I could re-use the printer mechanism instead of the receipt printers that I have bought off ebay in the past. They are relatively expensive (over £20) whereas the CP-10 can be had for half the price, if the CP-10 is listed as non-working. Unfortunately the CP-10 has a NiCd battery pack, as the printer mechanism take a fair current when running and the pack is used to supply that. This means that a lot of CP-10s have suffered battery leakage and failed. This is what had happened to my example. After a brief attempt to revive it I cut off the printer mechanism and attached a blue pill and some extra circuitry.
Over the years, I have accumulated many used computer power bricks. Although I could just use them by themselves to power other electronics with similar voltage and current requirements, I thought I would combine a few of them together as the input to a linear regulator so that I can make a powerful lab power supply.
In the event that COVID-19 hospitalizations exhaust the availability of FDA approved ventilators. This project documents the process of converting a low-cost CPAP (Continuous Positive Airway Pressure) blower into a rudimentary non-invasive pressure support ventilator that could help with breathing during respiratory distress. It’s an evolving project, but in it’s current form, it most aligned with the definition of a non-invasive pressure support BiPAP ventilator. This same project can also be used to create a reasonable low-cost Powered Air Purifying Respirator (PAPR) with filter adapter and mask.
A chaotic oscillator is an electronic circuit that can exhibit “chaotic“, nonperiodic behavior. A commonly cited example is Chua’s circuit, but there are many others. I always regarded these as carefully designed, rather academic, examples. So I was a bit surprised to observe apparently chaotic behavior in a completely unrelated experiment.
To test my LED Stair Lighting Controller boards I needed a 12V power supply that can deliver a lot of current. For this I chose a SP-320-12 from meanwell. However with the screw terminals it is not easy to use on a lab bench, also there is no display to monitor the output current. Therefore I build an enclosure around the PSU, and added a volt and ampere meter.