Hi fans -
it has been brought to my attention that some sellers on Ebay (and possibly elsewhere) advertise "improved" ACI PCBs for sale.
Here is my WARNING to you:
Do not confuse these "improved" ACI PCBs with the "Gen1" or "Gen2" improved ACI PCBs which I developed and which came with my Apple-1 IC kits (now sold out).
Instead, all these "improved" ACI PCBs advertised on Ebay I found (after I got alerted) are just based on the "Russian" Gerbers which were improved by the American Logan Greer, and released to the public. These improvements by Logan are cosmetic in nature and bring the "looks" of these PCBs closer to the originals. For instance, among other things, Logan substituted the small round IC pads against larger oval IC pads. Which indeed looks nicer and more "original". But none of these improvements by Logan changed the ACI circuit, which I did for the "Gen1" and "Gen2" improved ACI PCBs I developed and have written about in this thread:
For those who don't want to read that thread, here is a short summary:
My Gen1 improvements fixed the "volume indicator LED" circuit, added a synchronizer for the read data, and gave the ACI the capability to use 512x4 PROMs in lieu of the 256x4 PROMs of the original ACI. I added an "extended format page" which gives the ACI the capability to write and read Apple II cassette recordings and also do autoload and autostart recordings for the Apple-1, including checksum checks. Out of respect for Woz, I did not change his original ACI code to accomplish that. The "extended formatting" page is just an add-on you get when you start the ACI firmware at $C500 and not at $C100. If you start at $C100, you still get the unmodified ACI firmware as written by Woz. I made a Gen1 improved PCB based on the Russian Gerbers by Misha Mdesk, which he placed in the public domain (at that time Logan's cosmetic improvements did not exist yet).
These Gen1 improvements worked OK as long as a good quality cassette recorder was used, or, if AIFF or WAV files were played to the ACI via a sound card of a PC or notebook (or iPod, etc.). But it still had the fundamentally flawed TAPE IN circuit of the original ACI.
My Gen 2 improvements kept all the Gen1 improvements as they were and changed the TAPE IN circuit for a much, much better one which is in par (readback reliability wise) with the Apple II cassette interface (but does not need any negative supply voltage, so these Gen2 improved ACI cards also work in the Briel Replica-1). My improved TAPE IN circuit adds a few SMDs hidden under the DIL-8 socket of the LM311, and re-uses the exising leaded, vintage-looking resistors (but the circuit is much different). So the "looks" are preserved, compared to the original ACI.
My Gen2 improved PCB incorporating all my circuit improvements was based on the proprietary Gerbers of Mike "Newton" who also sells his "Newton" Apple-1 motherboards. His Ebay seller name is "newton-computer". The deal we cut allowed me to produce the Gen2 improved ACI PCBs and put them into my kits. After that, the rights reverted to him. He got the leftover PCBs from me and is preparing to make them available for sale, but the last communications we had revolved over his difficulty finding 512x4 PROM blanks for an acceptable price (some IC brokers now want up to and over $70 each, and two are needed for the ACI).
So please be patient, the solution is in the works ! Don't get deceived by "improved" ACI PCBs which are based on Logan's Gerbers, but do not include my mods. You can easily identify the "impostors" by not having the SMD circuitry between the LM311 pads. Here is a photo how the "real McCoy" looks:
This is the newest (and last) revision of the layout, optimized for the LM4040 shunt regulator, which you can only get from Mike. You can see a lot of tiny SMD "footprints" between the pads of the DIL-8 place on the left hand side of the PCB. This is part of the improved TAPE IN circuit I developed. The solder blobs you can see are part of the trick how you can hand solder these tiny "bird feed" components in.
If you can't see the "footprints" and traces for the extra SMD components on any ACI PCB, it does not have my "Gen2 improvements", period.
If you don't need my Gen2 improvements for the ACI, these other so-called "improved" ACI PCBs are probably OK for you, but you won't get a functional volume indicator LED, no extended format page, and the poor readback reliability of the original TAPE IN circuit.
So please, don't get confused about what is offered by these sellers and what you will get. Note that I don't claim they are doing this deceiving advertisement with the intent to defraud, it just so happens that in the context of Apple-1 ACI PCBs, the word "improved" may mean two different PCBs with different circuits. But I got enough angry email from people who thought that they were scammed. So be warned, and know what you buy, and from whom you buy.
- Uncle Bernie