ACI 2716 adapter boards came in from China

This is neat and I look forward to your results.

Some day I would love to make an ACI with the necessary improvements to need only 5V, and this EPROM modification. Original looks would be secondary; I want an easily available ACI for R1+ owners (I have a gen 2 Improved ACI from Uncle Bernie but that kit/card isn't sold by itself he told me). 

In post #3, skate323k137 wrote:

"I have a gen 2 Improved ACI from Uncle Bernie but that kit/card isn't sold by itself ..."

Uncle Bernie clarifies:

The reason for this is that all Gen 1 and Gen 2 ACI PCBs so far have been based on the "Russian Gerbers" which work, but they are not as close to the originals as I wanted. I made half a dozen Gen2 ACI beta test kits available at or below my own cost and got some encouraging results from the beta testers (except for one, who never responded). I gave the leftover unpopulated Gen2 ACI PCBs away with some of my famous IC kits and so far no complaints. The issue with the current state of the development is that I can't decide on which bias circuit should go into the Gen2 PCBs. They layout supports all planned bias circuit versions. But the only bias circuit that ever was unleashed on the world is the Zener diode based one and I needed to painstakingly hand select these Zener diodes for a more tightly controlled voltage than commercially available. This is NOT a viable way to make more than a  few of Gen2 ACI kits. I'm working on qualifying the other bias circuits which do not need component hand selection. And in the meanwhile I have put the Gen2 mods into a 'commercial' ACI layout which is the most accurate you can get, courtesy of the owner of the rights to this PCB layout he made. The remaining work is to repair my spectrum analyzer and to take a few measurements, and then make a few SPICE simulations and calculations. The SPICE test bench is already built and tested. After that work is done, I should be able to tell a) which bias circuit version to use, and b) how the matching / tolerances of some critical passive components must be specified to assure consistently good performance. After that (I think) the Gen2 ACI is ready for release and if there is a demand, there will be PCBs or maybe even kits available.

So don't despair. Things are moving ahead but how my projects work is that I have lots of them at the same time, and when a project starts to frustrate me I put it on the back burner and continue with another one.  Repairing spectrum analyzers is extremely frustrating, these are complex machines with a lot of plumbing and shielded modules inside, all conspiring against reaching the individual components which need to be replaced. If you thought that oscilloscopes are the most difficult to repair, think again. Believe it or not but this is the main reason why the Gen2 ACI project made not much progress the last few months. It's about decrepit measurement instruments unfit for the task at hand and my motivation to play "plumber" in the guts of 30+ year old spectrum analyzers is very weak. I designed and wire wrapped the DRAM card for the Apple-1 instead. This is how it goes with my projects. Mind you, none of these projects of mine are meant or fit to make any money for me. I have no motivation for that. Actually, I have zero motivation to earn any more of that not-so-funny green toilet paper (GTP) as it loses it purchasing power faster than you can earn it.  It seems that more and more people notice that and stop working. The motto for this is "laying flat" or "let it rot" with the younger generations. It once was known as "Going Galt" (from "Atlas Shrugged") for those less tender of age. I'm more the "Galt" type then the "laying flat" type, though.

Somewhere early next year,  the work on the Gen2 ACI hopefully should be completed. It then only depends on third parties and the demand from the Apple-1 community if it becomes widely available or not. I intend to put a few of my leftover PCBs in my famous IC kits once I don't need to hand select those Zener diodes anymore. I absolutely hate such menial work but it had to be done. Never again. Until the next project that needs it ;-)

- Uncle Bernie

softwarejanitor wrote:

 

A newly laid out ACI board with Uncle Bernie's mods (preferably using through-hole instead of SMD) and modded to use a 2716 or something like a 28C64 would be awesome.  Reliable and buildable using much more readily available parts.  I wouldn't mind at all that it didn't look exactly like a vintage ACI card as long as in general it looked relatively period correct.

Yeah, that is basically my 'dream,' this list hits all the points I think. I can be patient though, if it happens in time that's good enough :)  

I had an alike idea, it is untestest, SK1 and SK1A allow to replace PROMs on Apple I PCB or ACI, the jumpers (right of SK1A, they are SMD to have no Pins on backside) would allow to select standard ROM, Diagrom, ACI ROM, and some others.

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I some one is interested in the design files they are here but be warned it might not work at all: https://oshwlab.com/szillat/PROM-Adapter_copy_copy