If you already have many of the components for the kits, you can save some money by buying bare circuit boards. The various kit instructions have complete parts lists for each kit. I buy the parts from Jameco Electronics, and you can buy any parts you might be missing from them. If you have any questions about the exact parts you need, contact me and I will help you pick the correct parts.
This is a "wall wart"-style power supply that produces 2000 mA of current at +5V DC regulated, which is adequate for running the Original computer with the display attached or the 8-bit processor system with the register display. It has a 6-foot cord for the +5V output with a plug that fits the power-in jack on the computer kit boards. It has a USA-style plug for the electrical wall outlet. It needs an input of 100 to 120 V AC, at 50 to 60 Hz. If you are an international customer, please check if it will work in your area before buying.
This is a simple plug with leads that fits into the power-in jack on the computer kit boards. It is for hobbyists who already have a power supply capable of at least 2000 mA current at +5V DC regulated (a 10-watt supply) for running the computer kit and attached boards.
EPROM price: $5.80
GAL price: $4.70
The computer kits, disk and memory expansion kit, and 8-bit processor systems need programmed EPROMs. The disk and memory expansion kit, single-board Z80 kit, and the 8-bit processor need programmed GAL (generic array logic) ICs. These are supplied with the full kits, but if you buy the bare boards and use your own components to build the kits you will need to program your own EPROMs and GALs, or you can buy pre-programmed EPROMs and GALs here. There are various types for the kits, please check with me to make sure you are getting the correct pre-programmed ICs you need for your project.
I am offering custom kits for sale. If you have some of the components of these kits already, let me know, and I can put together a custom kit for you that has only the components you do not have. So, for example, if you have an 8251A UART in your parts box, I can reduce the price of the single-board Z80 computer kit by about $10, and send you a kit that has everything but the UART. I will do this for the other parts as well. Let me know what parts you already have, and I will give you a quote for your custom kit. I can also sell individual parts for the kits on a cost-plus basis.
A few other examples: I can make custom ribbon cables that allow you to operate the original Z80 computer with both the bus display and serial interface attached at the same time. I can sell you an "original" disk and memory kit with the memory configuration logic array implemented with discrete logic ICs instead of a GAL. I am very flexible on what I can make and sell. Please contact me if you have any special requests and I will do my best to accomodate you.