It's all soldered up on a perfboard about 2.5" x 4". There's a nice little project box that it fits into with no room to spare.
The project was delayed by the phenomenon known as 'decent weather'. Since we had a rather chilly weekend last week, I was able to put some time into it. The underside is something of a rat's nest of slender wires going here and there -- quite a mess, considering the total component count is 14 items. (There are three linear regulators -- the L7805's -- because the incoming signals from the bar control left & right are 12v, and would kill the PICAXE otherwise... I couldn't think of a dependable way around this. )
After a boatload of soldering, it was pretty satisfying to hook it up and have it work exactly as it was designed, right off the bat. To test the self-cancel, I still had to use a separate breadboarded PICAXE to simulate the pulses I'll get from the reed switch in the speedo.
After fighting for most of the project with a garbage Radio Shack soldering pencil that refused to tin, I broke down and bought a new Weller soldering station -- once I was about 90% finished. The new pencil is a dream to use, especially compared to the RS unit.
It's time to finish epoxying and squeeze this into its box with the OEM TCU's harness, so it plugs in where the original did. The second half is mostly hookup -- I'm replacing the '81-style bar control with a unit I reworked off of a '79 GS-something with self-cancels. The finishing touch will be to install a pair of super-bright LED arrays into the front signals; these will be wired to be on all the time as running lights (except, of course, when they're blinking).
The way this is set up, it's really not much of a stretch to conjure up a direct plug & play replacement for a deceased original TCU. Simpler than this unit, and certainly less money than an original -- provided you can even find one that's likely to work properly.
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