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Greetings from San Francisco, new member here so thank you in advance for the input and discussion on my topic. My Apple 1 board has many correct chips and dates codes but still searching for the most correct ones (the big one will be to replace the 6502 with a MOS white ceramic). For those of you who might have time, please open the two attachments and examine the current chips and date codes. I would be interested in which chips should be updated to reflect a 1976 pre-NTI board. Also, what week in 1976 would be the cut off for a correct pre-NTI board? The table below has an X in the last column when I think that chip should stay and a "?" to indicate a possible change.
I'm also aware that this type of replica that has all correct chip makers and exact date codes for 1976 only appeals to a very small group as most are satisfied with just a working replica. But I am hoping that those who like this type of challenge will help me. Thank you all!
I was thinking for a bit on how to respond to your post. There is some complexity to what you are asking. Only the first 50 Apple-1 have some sense of consistency to the chips/date codes and yes they are all 1976, as a matter of fact pretty much July and earlier 1976 date codes. Later pre-NTI may have dates codes up to the end of 76. NTI can have date codes into mid 1977.
Some of the date codes vary in the post 50 preNTI units.
I'm not sure I understand some of your columns, are you listing the chips you have now? It seems this way since CM2140 was never used on the original A-1. FYI: Pre-NTI boards are pretty consistent in that most of the chips are Fairchild not Signetics and some are 9NXX and some aren't. So that is another indicator that your listing is what you have for your replica since pre-NTI did not use Signetics 74S257.
So are you looking to replicate a Byte Shop early 50 or later 50? If I provide you date codes of an actual unit, you could go pretty insane and broke trying to track down the exact replacements.
Cheers,
Corey
Hello Corey and thanks for your comments! I completely agree that this is a complex subject and for the vast majority of collector enthusiasts, not something that they are much interested in. And maybe wisely so! I have read posts of members asking the question of why even do this. I believe you may have commented on the “why” in another post and for those few of us with this goal, it is indeed the “hunt” and the “challenge” of exactly duplicating the Apple 1 board. But of course, which board eh?
Regarding this challenge, we are indeed lucky that we have a couple of boards that are reproduced at such a high accuracy and finish. This one fact alone allows us the opportunity to pick which hobby goal one wants to engage in. I had settled on my target representation of a pre-NTI board to be that in general, of a 1976 example, not necessarily the first 50 or the later 50. From your observation that the later boards in 1976 included date codes to the end of the year, it seems to me that would be the best target board to replicate and prevent a total loss of insanity. Thanks for pointing this out and that alone helps me focus on which chips to next hunt down.
Sorry to confuse you with my table, but the columns labeled Chip #, Maker and Date is what is currently populated on the board. I have been in the computer business for many years, but I don’t solder so I purchased this board already built and working. I thought it would be an excellent start with my ultimate project of correct manufactures and date coded chips. Sounds like a need to loose as many Signetics as possible.
I’m trying to envision what it must of been like stuffing the boards in 1976 (apparently not in a garage). They must have bought the needed chips in bulk so yes they would have been of the same date range. But what if they had run low and their source was temporarily out of stock? If they scrambled to find another supplier, could they have had older stock resulting in date codes of 1975, 74 or even 1973? It is in this spirit that I am attempting to build an “exact” replica, not to mirror any one known example. I want to look at the finished board and think - it could of looked just like this!
No question that I will have to refinish the two PROMS with Apple logos and I see much work has already been done in this area by other members as well.
Respect,
Theodore
Republican of apple is produced after prolonged work out by the workers. All the themes of the https://businesspartnermagazine.com/top-5-marketing-skills-every-business-needs-growth/ are done for the apple. Such devices are done for the narrative and argument for the field work for the users at general level.
Hi Theodore -
I really like your quest for an Apple-1 clone with the correct date codes. Hope you have the required energy and patience to finish that ! (Unlike me, I gave up on it, I now just sell my IC stock off, but that's a long story). As I have pondered a long time over the possibility to make "perfect" Apple-1 clones which even would fool experts like Corey (no pun intended, Corey, as I finally came to the conclusion it's impossible) I have collected some thoughts on how to solve some of the issues of procuring the "right" parts. You can find a writeup in post #2 if this thread:
www.applefritter.com/content/wtb-apple-1-parts-dc-correct-most-important-mk4096n-11-dc-76-srague-5300-15v-39d-dc-7576
It's in the "Wanted" forum so it's unlikely that it has been read by many people (seems nobody is looking there). Hope this may get you some clues on how it could be done.
Here is another hint for you as you live in SF which is close to Silicon Valley. The semiconductor industry sometimes has the need to take a die ("chip") out of a plastic package and then transfer it into another package and put new bond wires in, so it will be fully functional again (but be aware there is a certain mishap rate). Nicknames for the procedure vary but in the company I worked for until retirement it was called "Scoop and Goop". There ought to be service companies who can do that. We have one here in Colorado Springs. They use the procedure to salvage die from plastic parts and then die attach them onto multilayer ceramic substrates (several die on one substrate), bond them, test them, seal them to make a complex hybrid ICs for customers not-to-be-named. It's expensive but not prohibitively so ! The same procedure and the same equipment could be used to transfer 6502 or 6520 die into ceramic packages. Alas, the side brazed ceramic packages you can buy today are not white. But any white vintage ceramic package with a suitable 40 pin leadframe could be used, the lid opened, the die and the bond wires removed, and then the wanted die could be put in. I think that if you negociate well you could get this done for less money than buying a white ceramic packaged original 6502 off Ebay (the last one I saw went for $1000 or so. One 6502 ! Weird !)
Just wanted to point out some alternatives. Hope this helps with your quest ! Keep us posted !
- Bernie
Hi all,
Recently decidcd to get into the Apple-1 hobby as well and have been purchasing to make myself a couple of boards with various "correctness". Something about how unique each board and its provenance is definitely interesting here. Started off with 2 Newton NTI boards, one of Unicorn's kits and one of Uncle Bernie (Awesome service and value). Got some stuff off eBay to "sprinkle" some affordable Unobtanium while saving for that holy grail white 6502. Managed to get a Signetics 6502 DC:7806 and a gold 323k DC:828 from an old arcade Breakout board too. Collected into of http://rlvintage.tech/1n4001.html and put them into a spreadsheet. Planning out to make 4 boards (2 NTI and 2 Mimeo (as soon as Mike Willegal has them again).
First off, it would impossible to make something that can fool experts even with all date correct chips. You still need to wave solder the board and get it to age almost 40 years. Not to mention, the board you are soldering in the first place was not made where it was made with how it was made back then. Its like having a Van Gogh recreated stroke by stroke but experts (especially with forensic equipment) can tell its not, by the pigments in the colors and canvas material, etc. But, would be cool to have a reasonably, visually faithful replica, and functioning too. Think this the best we can all aim to achieve, a board to be proud of and show off. Anways, here's what I found out as I was planning for one of the boards to be ultra authentic, which would be my final personal one to keep. I call it these the criterias for Chip Correctness.
1) Period correct (obviously '76 and below, unless Woz also invented a Time Machine to go into 80s and 90s to bring back bags of 555 and LM311)
2) Manufacturer correct (First batch used a lot of Fairchilds while NTI had a lot of Signetics)
3) Date Code correct (harder to achieve but that we can give some ICs some tolerance of say +/-5 weeks since there was definitely a mix when they got the parts back in 76)
4) Board correct (The Steves did not use the same ICs/parts for some, like the Bel 0.1uf in place of 1uf and that is only for First Batch and also 7451 over 7450)
5) Spec correct (Not sure if this is what it should really be called but there are variants for these chips like 7400A vs 7400N)
6) Marking correct (The right logo, logo placement, etc)
Of course, this is only based on my gatherings. And, I'm not sure which boards the website I used for my information is based of and if the details were obtained through the web or IRL. Its most likely a small sample and gathered from HiRes photos. Anyways. I think it adds to the mystery and legend of the Apple-1.
I'm also collecting my dream replica. I'm missing Signetics 7432, 74157 and NE555V to a full set of correct chips (so far only the video part of rows C and D. Besides rlvintage.tech there is another great resource with photos of the original Apple-1 - https://www.apple1registry.com/en/6.html.
That's awesome. Must have taken a long time to source them out. I doubt I'll get to filling out an entire row (BINGO!) and I'm also using some close enough/lookalike for the other components and more recent version of the big blue caps. Can only go so far.