Reddit:Electronics

I have a long standing fascination with nixie tubes and wanted to build something for a while.

I got this board of aliexpress with only basic clock and i simply could not waste it to leave at that so I have reverse engineered connections and disabled on board chip.

I have replaced boring stm chip with esp32 and now have a cool looking clock with functions like:

Timer, stopwatch, reminders, alarms, navidrom music player, adjustable RGB, wifi ntp sync etc.

All controlled via backed web-ui

I’ve been working on a custom Arduino wireless remote using an NRF24L01 module and a rotary encoder.

The photos show how the project evolved from a breadboard prototype to a fully soldered perfboard version.

The next step is adding an I2C LCD and refining the software.

I’d love to hear any suggestions or ideas before I move on to the next revision. What would you add or change?

I made up a schematic of the division unit for my recent calculator project, with some adjustments. I switched out a few chips with ones from the same family, but I tried to keep it as close to the original as I could. The original also only took 7 bits for the divisor as it only took up to 99 as an input due to the interface of the calculator. Definitely could be optimized.

This is my first time translating a circuit of this size to a schematic, so it might be... messy. Hopefully I didn't miss anything; I checked it over a few times. A few adjustments might be required.

"Start" must remain low until dividend and divisor are inputted. This signal must remain high until the XOR signal, from carryout and OR, is high, which then tells the circuit that the result is negative and to stop subtracting the divisor.

I have a video of the division unit from when i was still testing it as well. I plan and am working on creating a whole schematic of my calculator without any changes, but do beware that my demonstration of the unit isn't 1:1 as it's from early on in testing, same with the second photo. https://youtu.be/GKElo5Bfb7c

First time trying something like this!