Apple II S/N 5025 (continued)

After last month’s post about A2S1-5025, I received several requests for photos of specific areas of the machine that were not visible in the first set of pictures. Here you go:

This is the keyboard, removed from the case.

Rev 0 Keyboard (second version)

Rev 0 Keyboard (second version)

Bottom of the keyboard.

Apple II Rev 0 keyboard, second version - from the bottom.

Apple II Rev 0 keyboard, second version – from the bottom.

Apple part number 01-0425-01 is described in the Apple II/II-Plus Level II Service Manual (1981, Pre-Release Version, available in PDF format here – do a text search for “keyboard varieties” in the file) as “The first Apple keyboard,” but it is not. The early revision 0’s shipped with 01-0341-01, an example of which can be viewed here.

As with the Apple II board itself, the early days of production saw the keyboard undergo a number of changes more evolutionary than revolutionary. The circuit board was made shorter and wider to better fit the case, with the silver leaf plates formerly used to secure the keyboard to the plastic sacrificed to make room for the reconfigured electronics. The silk-screened Apple part number was moved from the lower right to left…

Apple II keyboard second version (01-0425-01)

Apple II keyboard second version (01-0425-01)

The encoder chip and associated electronics were migrated to the lower right…

Apple II Rev 0 keyboard encoder chip

Apple II Rev 0 keyboard encoder chip

These long, threaded, brass posts lined up with the spacers on the PCB to provide a mounting system.

Threaded brass posts affix the keyboard to the case.

Threaded brass posts affix the keyboard to the case.

The mounting set up is reinforced with these hollow spacers that also align the keyboard assembly on the brass posts.

Hollow spacers provide guides for the posts and reinforce the mounting.

Hollow spacers provide guides for the posts and reinforce the mounting.

Here’s the upper shell, removed from the base pan and keyboard.

Apple II Rev 0 case - upper shell

Apple II Rev 0 case – upper shell

Close up of the black nylon “velcro” lid fastener pad.

20160225_210347377_iOS

When trying to determine whether an Apple II is a revision 0 or some later production model, there are a few identifying markers on the motherboard that can quickly be verified. One of the indicators easiest to identify is the presence (or lack) of the color killer circuit, which includes a transistor visible on the PCB in the area to the right of the CPU, between rows F and H (there’s no row G), like so:

Color-kill circuit transistor.

Color-kill circuit transistor.

This circuit was added to production beginning with the revision 1 boards so it’s simple math: no transistor means the board is a revision 0.

All revision 0 boards, and only revision 0 boards, lack the color kill circuit. (I, on the other hand, lack grammatical skills apparently.)

All revision 0 boards, and only revision 0 boards, lack the color kill circuit. (I, on the other hand, lack grammatical skills apparently.)

Another “dead giveaway” that you’re looking at revision 0 board can be found under the 6502 chip. Or rather, not found. All Apple II boards beginning with the revision 1 run were assigned a part number which, early on, could be found by taking a peek under the processor. As an example, here’s what you see when you pry up the CPU on a rev 0 board, with the revision 4 Apple II Plus below it.

Rev 0. No part number under the CPU.

Rev 0. No part number under the CPU.

Apple II Plus rev 4 part number under the CPU.

Apple II Plus rev 4 part number under the CPU.

These memory select jumper blocks allowed users to upgrade their memory easily. Simply plug-in your new DRAMs and insert the appropriate jumper blocks to let the computer know how much memory it had to work with. The presence of these, while an indicator that you are looking at an early Apple II board, doesn’t guarantee a revision 0. Later boards shipped with them soldered in place and at some point they were removed altogether.

Revision 0 memory blocks, not soldered.

Revision 0 memory blocks, not soldered.

This is one that often gets missed in auction photos on eBay because of the awkward position you have to hold your phone in to get a clear shot, but a surefire indicator is the copyright date that appears just above the system ROMs and below the Apple Computer logo. Only revision 0’s are marked ‘1977’; every thing after that stamped with a 1978 copyright (or later.)

Only Revision 0 boards are (c) 1977.

Only Revision 0 boards are (c) 1977.

Someone asked for a shot of the underside of the 6502, so here you go. I assume “PHIL.” means it was manufactured in the Philippines. No idea what the other text might mean.

20160225_210838873_iOS

I’ve got a few more areas to cover, but that’s probably enough for now. I’ll knock the rest out in a third post next week.

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…

The Software Factory – AstroApple (Tape Distribution)

This archive contains a disk image (13 sector DOS 3.2 format) of the tape distribution of AstroApple, an astrology program by Bob Male, distributed by The Software Factory. The other side of the disk has the diskette distribution, but there were so many bad sectors that the FC5025 couldn’t image it.

Get the archive here.

Someone posted a scan of the manual here (free to view in your browser; downloading apparently requires free registration).

astroapple-manual

The Software Factory – BABBLE (Tape and Diskette Distribution)

This archive contains the 13-sector DOS 3.2 disk images for the tape and diskette distributions of BABBLE. What’s BABBLE? An ad in Softalk describes it this way:

“Have fun with this unique software. You write a story, entering it as a BABBLE program. As you write the story you specify certain words to be selected by the computer or entered from the keyboard at execution time. Run the program and watch BABBLE convert your story into an often hilarious collection of incongruities. The ways in which BABBLE can entertain you are limited only to your imagination. You can compose an impressive political speech or write poetry. You can plan a dinner menu. You can even form images on the screen or compose musical tunes with the help of BABBLE. The cassette version requires at least 16K of RAM and the diskette version requires at least 32K of RAM. BABBLE is written in machine language and runs on any Apple II computer.”

Get the archive here.

babble