As I was getting ready to put a brand new USEABLE keyboard in my original CoCo 1, I discovered the power button was GONE! Upon opening the case I discovered that it wasn’t just the black cap that fell off (which seemed the most likely scenario) but the entire poll was gone! How that is even possible is beyond me.
I got some direction from Bob Emery on how to wire what was left of the switch into an “always on” state and put a power bar at the plug end.
I figured I better make sure that there wasn’t something else wrong before sinking a bunch of $$$ into further upgrades. Thankfully, the fuzzy RF screen displayed “Color Basic” when powered up!
I consulted with the Community on both Facebook and Discord to try and source a new switch. We got CLOSE a couple times, but finally landed on what looked like the right one, but it was rated for .5 amps instead of, what the CoCo Hardware Manual called for, FIVE AMPS!
Further investigation – looking at the label on the back of the CoCo, provided some pertinent information:
While there is a lot I have forgotten from my high school electrical program, Ohm’s Law is still stuck in my head. If the wattage is only 15.6, that means the Amperage for the CoCo is only 0.13 Amps! Did Radio Shack just have an overstock of 5 amp switches they had to use up? I dunno, but a .5 Amp power switch SHOULD work just fine. ORDERED! (got 3 actually….just in case I botch the repair)
(Subsequent discussion on the CoCo Discord channel questioned the “5 amp” value of the original switch. Upon deeper investigation that value cannot be found anywhere! However, a closer look at the power supply circuit revealed the switch was on the OTHER side of the transformer where the power had already been reduced, so the .5 Amp switch looks to be O.K. anyways!)
https://www.digikey.com/en/products/detail/knitter-switch/MPBS42-H01L-F14/15296071
What happened next was a bit of an adventure…
