Yesterday was one of those freakish days that are so rare I often believe they don't exist. I call them freakish because things go right. Things work. And I'm just not used to that.

To make a long story short (because I don't have much time), the revision G boards for my RC4 device arrived. Coincidentally, I also received four proximity sensors for my robot, and a new Jameco catalog. It was a day for electronics, I guess.

Here is a picture of the new board in its raw, uncut form:


There are actually six circuits on this board - RC4 is in the top right corner (you can see "RC4" printed on it). One of the circuits is an RS-232 interface board that lets me talk to RC4 via the computer, and the other large segment is my BX-24 Pilot board, which is actually two layouts on one board, that will serve as an auto-pilot carrier board for my Basic-X module that I will use in a flight test.

The remaining three little circuits were my first attempt at creating and assembling a circuit with SMD (surface-mount) components. I must say that I was immensely successful - very pleased with the end results. I don't have pictures of them, but they are used for my PCM radio to boost the signals from the PCM receiver that feed the Victor motor controllers on my Trike ground vehicle. As with everything else yesterday, they just worked. And now I can use my radio that has the ground-based frequency with my Trike, rather than the one I was using that is for aircraft use only (I don't want to get in trouble...or bring someone else's airplane down).

I cut up the boards, placed a will-call order to Jameco, took 26 minutes to go to Jameco and pick up the parts I needed, came back and cut up the boards, then immediately began assembling them. I assembled the booster boards (with the SMD components) first, followed by the RS-232 interface board (sorry, no picture of that, either), followed by RC4. Here is a shot of the Revision G board with all the components installed (except for the PIC chips, the 12 MHz oscillator and some jumper blocks):


I tested the RS-232 interface board and it just worked. So, I decided to plug in the RC4 board and test it. I simply pulled the PIC chips from the Rev. F board and plugged them into the Rev. G board and fired it up. And guess what? It just worked!

Among the parts I got from Jameco were some PIC16F648A microcontroller chips. They are drop-in replacements for the PIC16F628s that I was using, but they have twice the code space (4K!) and more RAM and more EEPROM data space. So I burned the firmware into one of them and plugged it in in place of PIC1, and - well - it didn't work exactly right, but that was because of a minor tweak I had to make to the code to tell the assembler I was using a different chip - but then it worked! It just worked! So now PIC1 is using the PIC16F648A, because it needs the expansion room (I was bumping up close to the 2K limit of the 16F628).

So here is RC4 Revision G in all its glory, with all the components and jumpers installed:


This is my test/development version, so I have jumper blocks installed where I might otherwise just solder a wire across on the board. Makes things easier for testing when I can just use a jumper block to change the configuration. For a flight-ready version, I would not install all the headers and would probably solder the oscillator right to the board (rather than have it socketed), and if I had in-circuit programming capability - which I don't - I would solder the PICs right to the board. All this to reduce weight.

And here is the beast on the development/testing platform (by the way, you can actually kind of see the RS-232 interface board in this picture off to the left in orbit around the planet on my mouse pad):


So far so good! I can't want to get it into a vehicle. I am still ironing out some final details (including that one last issue on my high-priority list that keeps me banging my head). Soon I will have to add a Revision G section to the web site. I'm actually trying to wrap up Revision F before moving on. But you know, I just realized that the letter "F" has been a miserable experience for me this year. Remember all the tragedy with my hard disks crashing, etc.? My "F" drive?

OH MAN! I can't WAIT to get past this "F"!