"I built an EPROM card to use in the 44 pin bus in my Apple 1 computer. It had on it two 2716 EPROM's. The 2716 was a 2k memory chip. I had a new monitor and a dis-assembler on the chips. To use this card I had to first unplug the two Apple Proms on the motherboard. As you can see I did not solder the sockets, but wire wrapped the card instead."
Entering data by hand is a slow and cumbersome process. Storing the code on some sort of media, even if that media is merely a cassette tape, is far more efficient. As a consequence, the Apple-1 Cassette Interface was a popular add-on. Many programs were available from Apple on cassette, such as BASIC, Dis-Assembler, Blackjack, Hamurabi, and Luner Lander.
Joes tell us, "If I remember right, you pulled the 6502 chip and put in the 6800 cpu and all the parts and you had an Apple I based on the 6800 cpu instead of the 6502 cpu. I also believe that there was a law suit by Motorola who had the 6800 chip because MOS Tech who came out with the 6502 chip were all engineers who left Motorola and helped on the 6800 cpu and the 6502 cpu could use all the instructions that the 6800 had and was faster."
The case is built like a tank and cost Joe around $50 back in 1977.
The top switch is for the printer. When you throw it, you get a print out to the screen and a hard copy from the printer. Below that switch is a red LED which is hooked to the cassette interface. Every time the tape was read or written to the either flicker or stay on read, depending on the level at which it was being accessed. The next switch to the left is for the cassette interface. When you wanted to read a tape you would have to throw this switch. To next switch to the right was also for the cassette interface. This one controlled writing.
Back in 1977, Joe stored his Apple 1 in the below pictured briefcase. The transformer and main boards were mounted and the keyboard was also stored inside. All you had to do was pick up the briefcase and your monitor (TV) and you had a portable computer that could go anywhere.
All IC's are installed in sockets, thus simplifying repairs or
hardware troubleshooting. The board has sockets for up to 8K bytes of
the 16 pin, 4K type RAM, and the system is fully expandable to 65K via