Hey all. Yeah, it was me that posted the thoughts on doing something as an inline-adapter in the other thread along with my prototype. I tried to find some reasonable prices for getting some fabbed, but nothing got me to my target price of $30 shipped, ready to install. (Meaning, I couldn't get the cost of goods down to less than $20 per set of boards not factoring in my time to solder everything in, take orders, ship product, payment fees to even make a tiny profit off them). If the rest of you who do this for a living can do so, more power to you, as I definitely don't have the time to spare to make the net $5 per set for the hour I would invest in each on average soldering, testing, accepting orders, packing, labelling, shipping.
The other problem was finding a "foolproof" way to have the buyer connect to the ground lead for the lamps without picking the wrong connection and blowing things up. That involved another board to interconnect through a AUX Driver board that was readily available on the back of the lamp board in the backbox of some games, but definitely not all. In which case I didn't have the time to research all of the possible permutations and along with selling my Bally game, and seeing others take this effort up, I quit exploring it.
However, oddly enough, I now have 4 OTHER early Stern/Bally pins that friends have got that are asking for the very same ability -- to put LEDs in without investing in the $100 board. So, looks like I have to hand build a few more of my prototypes or teach them how to do it and just inspect their work Or if they wait long enough, purchase it from you guys.
As I posted in the other thread, here was my prototype which worked great in a Bally Vector, and a circuit layout I started with but never completely finished. Good luck with your project!
Optimized (smallest fiberglass size) and with AuxExpander .156 passthru adaptor to get ground wire:
OptimizedAndAuxExpanderAdaptor.png
Rough design with prototype pics:
PCBLayouts.png
Installed.jpg
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