Apple II S/N 5025

A few people have suggested that I document my revision 0 Apple II computer, so here you go.

I obtained this computer in 2014, as thanks in part for helping a grieving widow organize and clear out her late husband’s vintage computing collection. The computer does not work. Photos and stuff start here:

Apple II and Disk II Drive

Apple II and Disk II Drive

This is a revision 0 Apple II, one of the first 6000 produced. It was made late in the run, bearing case number A2S1-5025.

Apple II serial number sticker

Apple II serial number sticker

According to the accompanying receipt, this Apple II was purchased at a store called Computer Workshop of Kansas City on North Oak Street in Kansas City, Missouri on July 19, 1978, more than a year after the official introduction at the West Coast Computer Faire in San Francisco. The original owner paid $1,197.44 ($1,150.00 + $47.44 in tax) for the computer. According to the US government’s CPI inflation calculator, that would be $4,358.83 in 2015. The receipt unfortunately does not have the Apple II’s serial number written on it but I have no reason to doubt its authenticity.

Apple II S/N A2S1-5025 - sales receipt

Apple II S/N A2S1-5025 – sales receipt

Here’s a look at the base pan.

Apple II Rev 0 S/N A2S1-5025 - base pan

Apple II Rev 0 S/N A2S1-5025 – base pan

The motherboard bears the serial number 5206, handwritten in black permanent marker. The discrepancy between case and board numbers is due to the fact that Apple also sold the II as a board-only DIY kit to hobbyists. These boards drew from the same pool of serial numbers but didn’t come with cases. The white serial number square is beginning to flake away and I’m concerned because I don’t know how to stop this process.

Rev. 0 Apple II - board number 5206

Rev. 0 Apple II – board number 5206

At some point, the original power supply was replaced with this later one. I haven’t had any luck locating a unit for sale that would be period-correct.

Rev. 0 Apple II - upgraded power supply

Rev. 0 Apple II – upgraded power supply

Here’s a photo of the 1977 copyright date found on revision 0 boards, and the CPU. The datecode on the 6502 reads 7807 – the 7th week of 1978. Oriented just above the chip in the photo, you can see the ends of the dark olive green slot connectors that Apple used in the latter stages of the revision 0 production run.

Rev. 0 Apple II - 6502 CPU

Rev. 0 Apple II – 6502 CPU

Here’s a close up of the machine ROMs and a row of DRAM chips. The date codes all look right for this machine.

Rev. 0 Apple II - ROMS and DRAMs

Rev. 0 Apple II – ROMS and DRAMs

Most RF modulators installed in these early Apple IIs were the “Sup’R’Mod” type, but the one installed in my Apple II looks like a generic version.

Apple II Rev 0 RF Modulator

Apple II Rev 0 RF Modulator

Here’s the keyboard, with the raised power light.

Apple II Rev 0 keyboard

Apple II Rev 0 keyboard

… and the keyboard PCB with the inspection date of May 10, 1978.

Keyboard Inspection Stamp

Keyboard Inspection Stamp

The Disk II drive is an early model, bearing serial number 00562. According to the accompanying paperwork, the drive was purchased on September 27, 1978 at the Team Electronics store in the Conestoga Mall in Grand Island, Nebraska. At some point, a write-protect control switch hack was installed.

Disk II Drive, S/N A2M0003-00562

Disk II Drive, S/N A2M0003-00562

One cosmetic difference between the early Disk II drive models and later ones (aside from the rainbow cable) is visible on closer inspection. The lower area of black plastic on the face plate is shiny on the earliest Disk II’s. In later examples, the finish has been changed to matte. I have vague memories of Tony Diaz explaining why they made the change, from some long-ago KansasFest, but it escapes me.

Disk II faceplate - old version

Disk II faceplate – old version

Disk II faceplate - new version

Disk II faceplate – new version

Here’s the Disk II Drive Controller card. Based on the date codes on the chips. the P5 and P6 PROMs were replaced at some point.

Disk II Controller Card

Disk II Controller Card

Here’s the receipt for the Disk II Drive from the Team Electronics store.

Disk II Drive Receipt

Disk II Drive Receipt

The case lid…

Apple II Rev 0 case lid

Apple II Rev 0 case lid

… and the underside of the lid.

Apple II Rev 0 case lid bottom

Apple II Rev 0 case lid bottom

The warranty paper work for the Apple II consisted of this card. The one that shipped with the Disk II Drive is identical.

Apple II Rev 0 limited warranty card

Apple II Rev 0 limited warranty card

And that’s pretty much it. The computer doesn’t work – you can see the problem here:

I’ve done all the simple troubleshooting (chip swapping, etc) that I know how; it’s probably a problem for a skilled electronics technician. Maybe someday…