Early Apple II+ - Rev 3 board?

12 posts / 0 new
Last post
Offline
Last seen: 7 months 5 days ago
Joined: Oct 9 2013 - 19:33
Posts: 372
Early Apple II+ - Rev 3 board?
AttachmentSize
Image icon IMG_7064.jpg4.1 MB
Image icon IMG_7067.JPG3.79 MB
Image icon IMG_7069.JPG3.72 MB
Image icon IMG_7071.JPG5.33 MB
Image icon IMG_7072.JPG2.55 MB
Image icon IMG_7074.jpg5.02 MB
Image icon IMG_7075.JPG2.26 MB
Image icon IMG_7076.JPG2.45 MB
Image icon IMG_7077.jpg901.72 KB

Hey all, just picked up this II+ and it is the earliest revision II+ I have ever had. Serial #4068.

It appears to me it is a Rev 3 board based on the photos (see attachments) and the research I have done, including this site and others.

Am I correct that this is a Rev 3 board? The II+'s brother came with it (S/N 7715) and it has the same date code on the mobo (33rd week of 1979) but I have not yet dismantled it to inspect further (still playing with his older brother 4068!!)

Alas the ram IC that was in the socket where the language card plugs in was not with the machine. While I have not inspected every chip yet, minus the Applesoft ROMs many of the chips I glanced at (including the CPU) are original as the date codes are all 1979. I'm sure there may be some that were replaced, I have not as I said removed, inspected and replaced every chip yet as I just got the machines last night.

Any thoughts on the mobo revision and any other items would be appreciated. The PSU is one of the dual voltage ones I have seen before (and have a few) that does 115v and 230v with a switch on the back of the PSU (sorry, did not photograph that yet)

It was in fantastic shape when I took it out of the box, needing minimal cleaning so far (still cleaning the case, which is also in very good to excellent shape)

I'll likely replace the ROMs with older, age appropriate date coded ones if I have them (which I believe I do)

Is it possible this would have come with Integer ROMs and then been switched out? I did not think a II+ would have come with anything but Applesoft ROMs but I have no experience with ones this old. Late 1979 seems unlikely to have been anything but Applesoft installed. Just that with several of the ROMs with datecodes into the 80's I was unsure how this may have been originally outfitted.

My favorite part is the character ROM, which matches the ram nicely. I love playing with these old machines, especially now that I can take them apart and mess with their innards, something I would never dare due as a child since it was Mom and Dad's $$ that paid for them back then!! Smile
Zan

Offline
Last seen: 7 months 5 days ago
Joined: Oct 9 2013 - 19:33
Posts: 372
Re: Early Apple II+ - Rev 3 board?

Added a photo of the ROMs (last attachment) that I believe would be appropriate for this computer. Any thoughts?
Thanks,
Zan

Offline
Last seen: 4 months 1 week ago
Joined: Jan 22 2015 - 12:32
Posts: 7
Re: Early Apple II+ - Rev 3 board?

Nice find! Looks to be in great shape. I love the gold RAM! Definitely a rev 4 motherboard. In 1979, Apple was still offering the II and II+. If you wanted Integer ROMs, you got the II and if you wanted AppleSoft ROMs, you got the II+. It wouldn't have come out of Apple with Integer ROMs.

Offline
Last seen: 4 months 1 week ago
Joined: Jan 22 2015 - 12:32
Posts: 7
Re: Early Apple II+ - Rev 3 board?

Just noticed the part where the motherboard date codes for those two machines are in the same week. That is VERY weird. I didn't think they were cranking out 3500 of these in a week. I have an all original II+ here (S/N 8490) and it's motherboard date is 40th week of 1979. It is also a rev 4 motherboard. Your 7715 in 33rd week to my 8490 in 40th week would mean there were at least 775 units produced in those 8 weeks, or somewhere around 100/week. Something sounds a bit fishy with the 4068.

Offline
Last seen: 7 months 5 days ago
Joined: Oct 9 2013 - 19:33
Posts: 372
Re: Early Apple II+ - Rev 3 board?

Thanks for the comeback. Actually I believe it is a Rev. 3 board, which is what I was trying to determine definitively.

if you believe some of the online info (see the link in my first post) the "Rev. 4" was actually a Rev. 3 board.

I was under the impression a true "Revision 4" board did not have the Ram Configuration Blocks.

I took the mobo date more as a result of how many mobos they produced in a given time frame as opposed to how many complete machines.
Zan

Offline
Last seen: 7 months 5 days ago
Joined: Oct 9 2013 - 19:33
Posts: 372
Re: Early Apple II+ - Rev 3 board?

So, upon closer inspection of the 7715 CPU it appears it is a 7938 date code on the motherboard, not 7933 (sorry, under the dust they looked the same!!)

In trying to wipe the dirt off what little faded ink was still on the stamp now looks like 793:-, but that's ok!!

So the motherboards were made close to each other, but just over a month apart. Not sure what would be "fishy" about the 4068. I sold a II+ s/n 8381 that had the same datecode of 7940 as yours and another s/n 14909 with a date code of 7946. More than 6000 units later in only 6 weeks. So again, what would be fishy?

Thanks for your input and insights. Back to the main question, is it a revision 3 or revision 4? I understand the silkscreened info on board that I photographed but based on online info from multiple sites it is not clear to me if it is a Revision 3 or Revision 4. I'd love for those more knowledgeable than I to chime in (wait....that's most everyone here so get ready for thousands of posts!!)

Zan

Offline
Last seen: 4 months 1 week ago
Joined: Jan 22 2015 - 12:32
Posts: 7
Re: Early Apple II+ - Rev 3 board?

Well, you can't believe everything that you read on the internet. If the revision 3 part number 820-0001-03 was never made, then what board is this that I have here?

Hmmm...I can't figure out how to upload a picture. Just imagine a picture of a rev 3 motherboard here.

Offline
Last seen: 7 months 5 days ago
Joined: Oct 9 2013 - 19:33
Posts: 372
Re: Early Apple II+ - Rev 3 board?

Like I said, that's why I was confused. Conflicting information.

Yeah, I hate that you cannot post images into posts after the initial post on this site. You have to put the photos online and link to them either through a link or using the inline image tag. Those are the only ways to add photos to any post beyond the first.

I assumed there was a revision 3 stamped board but again since this was the earliest II+ I have ever owned and the only II's I have had were Rev 0, I am relying on others to inform me.

Thanks again,
Zan

amauget's picture
Offline
Last seen: 3 days 18 hours ago
Joined: Jan 3 2011 - 11:34
Posts: 341
Re: Early Apple II+ - Rev 3 board?

Hello,

Definitely a Rev 4 :
- 820-0001-04 silkscreened under the CPU
- REV 4 engraved on the motherboard (revision number visible through the hole of connector #4, see picture IMG_7071.jpg)
- Soldered RAM blocks. In previous revisions, they are in sockets.

All these information are in Jim Sather's Understanding the Apple II book, in appendix G-2.

Offline
Last seen: 7 months 5 days ago
Joined: Oct 9 2013 - 19:33
Posts: 372
Re: Early Apple II+ - Rev 3 board?

Hello,

Definitely a Rev 4 :
- 820-0001-04 silkscreened under the CPU
- REV 4 engraved on the motherboard (revision number visible through the hole of connector #4, see picture IMG_7071.jpg)
- Soldered RAM blocks. In previous revisions, they are in sockets.

All these information are in Jim Sather's Understanding the Apple II book, in appendix G-2.

Thanks, that was mine and others' assumption, just like to know for sure when dealing with something I've never had before. That's why I took the closup of the Rev 4 under the slot, seemed pretty clear but every time I think I know something I find out I know a whole lot less than I thought I knew Smile

Have a bunch of stuff I'll be posting shortly with the "what the heck is it?" title! Smile
Zan

Dog Cow's picture
Offline
Last seen: 5 years 7 months ago
Joined: Dec 11 2008 - 16:26
Posts: 554
Re: Early Apple II+ - Rev 3 board?

Here is a picture of a Revision 3 motherboard in my Apple II Plus.

Rev 3 has removable RAM configuration blocks. The Rev 4 has them soldered down. I have both of these two motherboards.

MarkO's picture
Offline
Last seen: 3 months 2 weeks ago
Joined: Dec 10 2011 - 16:26
Posts: 689
Re: Early Apple II+ - Rev 3 board?

I have a Rev-03 Apple ][ too.

So I BELIEVE they exist....

MarkO

Log in or register to post comments