Page last updated Nov 6 2023. I built a Lee Hart 1802 MemberChip board in Nov 2020. Here's some of the
build details in photos and brief descriptions. I've made a number of mods not in the kit. Also there's
some errors I undid. Current information on the 1802 MemberChip card can be found at
Lee Hart's MemberChip sales page. It's also featured in the 2023 Hackaday contest
currently at this Web page. - Herb Johnson
parts as provided by Lee Hart's kit.
printed silkscreens on both sides of paper
I pasted two photocopies (one mirrored) on one piece of paper, to assist me in construction. CPU side of circuit board
ROM side of circuit board, some components installed
I added a 3-pin socket for ceramic resonator, to change speeds.
install socket pins from strip, even for TTL
I used a 40-pin socket to align the header and CPU socket
I used a 20 pin header with long pins, for the 20 pins of the 1802 which provide data and I/O signals.
That becomes the I/O expansion for the board. The other 20 pins are a short 20 pin SIP socket.
installed CPU socket RAM already installed
I had to pull the 74HC573, installed backwards
Photo checks holes (vias) for damage
had to remove a PC trace this board had a flaw
installing the ROM socket
another view of the ROM socket
view of the 20-pin header and the 6-pin power/serial header
See how I used red & black wire insulation to mark +5 and ground
completed board on CPU side
completed board on ROM side
The USB/TTL dongle
USB/TTL dongle wired to MemberChip
Windows PC display (terminal program) of MemberChip ROM in operation
MemberChip with Motorola 6820 PIO on application board
The board was built on a plain protoboard with a female socket to match the 20 pin header.
It was hand wired and soldered, no copper needed.
This page and edited content is copyright Herb Johnson (c) 2023. Contact Herb at www.retrotechnology.com, an email address is available on that page..