Hi Folks -
this week I finally got the PCBs from Newton Mike including an ACI.
I immediately proceeded to build the ACI, but decided not to follow the original circuit with the LM311 comparator.
Instead I did a few little cuts on the PCB and installed the components such that I have the LM741 based circuit from the Apple II.
The reason for this decision was all the bad experiences with the original ACI as documented on Applefritter and elsewhere.
I do not want flakey unreliable junk in my builds, to hell with authenticity here.
Based on the great reputation of the Apple II cassette interface, I expected a great outcome.
No so !
It did not work at all. Despite I had tested it on the lab bench (see attachments).
First I was bold and tried to load BASIC from a 22 year old cheap crappy dictaphone style cassette player with horrible tape wow.
Not one success at any volume setting.
Then I was humbled and tried to load BASIC from a sound file played on a notebook.
No success either.
Then I wrote some diagnostics routines and found the culprit.
A design bug.
After fixing this I could load BASIC even from the crappy dictaphone style cassette player. Every. Single. Time.
At any volume setting except very low and very high.
This said, I am getting curious what others may have done to improve the ACI. Maybe I have just rediscovered a fix that already exists.
So, comments from all the Apple I gurus lurking on this lists are much invited.
(If anyone wonders why I did not do a search for other solutions before I tried the mine, well, I do this to kill time with some intellectual challenge that prevents brain rot so many retirees are suffering from. Further, did you ever hear the old adage that six months in the laboratory can spare you six hours in the library - - - which would be the internet today).