Exploring The Gakken FX Micro-Computer

Early computer kits aimed at learning took all sorts of forms, from full-fledged computer kits like the Altair 8800 to the ready-made MicroBee Computer-In-A-Book. For those just wanting to dip their toes in the computing world, many low-cost computer “trainers” were released, and Japan had some awesome ones. [Jason Jacques] shows off his Gakken Micro-Computer FX-System (or is it the FX-Computer? Or maybe the FX-Micom? It seems like they couldn’t make up their minds). In any event, it was a combination microcomputer and I/O building blocks system running a custom version of the Texas Instrument TMS1100 microprocessor. Specifically designed to introduce users to the world of computing, the included guide is very detailed and includes 100 example programs and lots of information on how all the opcodes work.

This 4-bit system is similar to the Kenbak computer, with a very simple instruction set and limited address space. However, adding electronic components in plastic blocks brings this machine to a new level of interactivity. Connections can be made to and from the microcomputer block, as well as to the on-board speaker and simple input/output pins.  The example circuit displayed on the front cover of the box enables the microcontroller to connect to the speaker and allows a switch to light up a small incandescent bulb. We can imagine many users wiring up all sorts of extra components to their FX-Computers, and with the advent of 3D printing, it wouldn’t be difficult to create new blocks to insert into the grid.

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Bil Herd: Computing With Analog

When I was young the first “computer” I ever owned was an analog computer built from a kit. It had a sloped plastic case which had three knobs with large numerical scales around them and a small center-null meter. To operate it I would dial in two numbers as indicated by the scales and then adjust the “answer” by rotating the third dial until the little meter centered. Underneath there was a small handful of components wired on a terminal strip including two or three transistors.

In thinking back about that relic from the early 1970’s there was a moment when I assumed they may have been using the transistors as logarithmic amplifiers meaning that it was able to multiply electronically. After a few minutes of thought I came to the conclusion that it was probably much simpler and was most likely a Wheatstone Bridge. That doesn’t mean it couldn’t multiply, it was probably the printed scales that were logarithmic, much like a slide rule.

Did someone just ask what a slide rule was? Let me explain further for anyone under 50. If you watch the video footage or movies about the Apollo Space Program you won’t see any anyone carrying a hand calculator, they didn’t exist yet. Yet the navigation guys in the first row of Mission Control known aptly as “the trench”, could quickly calculate a position or vector to within a couple of decimal places, and they did it using sliding piece of bamboo or aluminum with numbers printed on them.

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