Great design with thorough documentation and instructions!
For PLC14500-Nano 1-bit Single Board Computer REV.C
This kit is a great design with thorough documentation on GitHub. For an intermediate to advanced builder, the build and use instructions are excellent, including tips for positioning components, and are available on GitHub and also included with the kit as printed copies! The board design uses good pad sizes for hand soldering, so build went smoothly. Having all the LEDs and switches to slow or step the clock makes it easy to see what is happening and is very helpful for debugging programs! Even with most of the LEDs on, the unit only consumes about 100 mA of current at 5 V.
I built my unit using DIP sockets for the ICs and pin header sockets to mate with the headers on the Arduino Nano. This is not required - sockets are my preference and I happened to have enough of each size on hand.
I found two minor issues with the timer: First, the Tindie description says the timer range is 0.5s to 30s, but the "rev b" schematic says it is 1s to 7s which is what the kit does since the parts that came with the kit match the schematic. Second, if the timer is repeatedly triggered by a program running at full speed (and not based on the user pushing a button or flipping a switch), the timer period can be much shorter than expected. I believe this is because the 470 uF capacitor (C4) doesn't have enough time to fully discharge before the next trigger. I replaced C4 with a 10 uF capacitor and RV1 with a 1 Meg ohm potentiometer, which gives a consistent timer period with a range from 1/40 of a second to 11 seconds.
Shipping to the United States took less than a week, which is outstanding in my experience! (Your mileage may vary.)
Overall, this is an excellent kit for experimenting with the MC14500 Industrial Control Unit, a fascinating old chip!
