About

Introductions

My name is Steve García. I was born and raised in Southern California, USA and haven’t ever left. I discovered computers in college. (I wished there were computers at my high school.) It was “love” at first sight. Professionally, I started on the hardware side of the business; administrating Novell Netware, Microsoft and Apple Macintosh networks. But I’ve gradually moved over the software side. I am currently a software developer for a pharmacy management software company.

And I have been exploring the retro-hardware world for the last few years.

I first became interested in home-made computers a few years ago when I stumbled onto Dr. Scott Baker’s YouTube video Building a Zeta 2 Single Board Computer.
I hadn’t realized people actually built computers by hand, with a soldering iron. I had assumed, since the time of Steve Wozniak, only corporations could design build computers. Only later did I discovered that the computer could be designed and built by individuals. Incredible.
 
Well, I watched the 14 videos Dr. Baker had posted on YouTube about Spencer Owen’s RC2014 computer. I explored Grant Searle’s website, Tindie and discovered the RetroBrew Computer Wiki.

My First Steps

I wanted (needed?) to build one of the kits. I had never soldered anything in my life. I bought a cheap soldering station, some solder and a few “easy” electronic kits. I put the kits together with probably the ugliest solder joints ever seen. Miraculously, they worked.

Surprised, but slightly confident, I bought the Sergey Kiselev’s Zeta SBC V2 and the ParPortProp PCBs from Todd Goodman of the RetroBrew Computers Wiki. This was quickly followed by large orders of parts from Mouser and Jameco along with a couple of hard-to-find items from EBay. And when everything arrived, I heated up the soldering iron.

Taking my time, I put together the Zeta 2 SBC over two weekend. After the last solder point was made and the Flash ROM was programmed with a newly purchased MiniPro TL866A, plugged in a serial adapter to my laptop, plugged in the 5V power supply, and it worked…unreliably.

What I mean is sometimes it would work, sort of; and other times, not at all. Using a slower (1.8432 MHz) crystal oscillator proved to be more reliably, but not completely. I checked every socketed chip, examined every solder joint and re-soldered a few, but had no luck. I removed all of the ICs and, using the schematic and a multimeter, tested every trace for continuity. Again, no success. 

Two Times A Charm

I gave up on the Zeta 2 SBC out of frustration and decided to try the RC2014. I order the RC2014 Pro – Homebrew Z80 Computer Kit. Again, when the kit arrived, I heated up the solder iron.

Being extra care, I built the kit in a three-day weekend. I checked all of my joints as the build went along. And at the end when I connected the power supply, the RC2014 Pro worked…reliably. Awesome!

I “played” with the RC2014, installed some CP/M software (Turbo Pascal being the first since I was always a Borland fan) and then I got bored. I wanted to design my own computer. It was about this time that I discovered KiCad.

Actually, the

First Time Was a Charm

too.

Before I get too far, let me tell you the conclusion of the Zeta 2 SBC. That wouldn’t be fair to Mr. Kiselev. It turns out, at the time, that I didn’t know I was suppose to clean up the flux residue after soldering the board. After a thorough cleaning with isopropyl alcohol, the Zeta 2 SBC ran reliably at high speeds. Apparently, the flux was slightly conductive.

Learning KiCad

I studied KiCad tutorials I found online and watch various KiCad videos on YouTube. Since it was a simple and proven design, I decided to adapt Grant Searle’s 6-chip Z80 Computer  design to a PCB as my first KiCad attempt. Laying out the schematic was straight to the point since it was generally Grant’s design (with only a few modifications from me), but facing the challenge of laying out the traces on the PCB was intimidating. At first I tried to use the auto-routing functionality of KiCad, but was disappointed. So I sat down at my computer and forced myself. I had a set of boards manufactured by JLCPCB and about ten days later, they arrived. I built one board, flashed the ROM and plugged in the power…and it worked. Amazing.  

Grant Searle’s Six Chip 56K Z80 SBC
Grant Searle’s Six Chip 56K Z80 SBC, Front
Grant Searle’s Six Chip 56K Z80 SBC
Grant Searle’s Six Chip 56K Z80 SBC, Back
Under Construction