filing frontpiece

Finally, I took it out of the vice and finished off the areas that were hard to get to while it was held by the vice (e.g. the inside edges, etc.):
filed frontpiece

There are two endpieces that go on either end of the frontpiece to hold it in place:
endpiece

I reversed both of these, so that the metal brackets pointed into the case, rather than out of the case:
reversing endpiece

Next I screw on the endpieces:
screwing on endpiece

I then mount the assembled frontpiece (e.g. with the endpieces attached) into the front of the housing:
mounting frontpiece

The frontpiece is screwed in, and attached to the metal housing:
tightening

Finally, after I'm finished doing all the metalworking, I install the mainboard:
comp

Design of the power supply

strip wire

Together with some additional filter capacitors I added right at the terminal block, I then screw in the wires, into the screw terminals:
screw terminals

I now have a nicely wired power connector:
wired power connector

Some important decisions need to be made about the power supply. I decided to use a Powertrends Integrated Switching Regulator shown here:
powertrends ISR

It is important to note that the control voltage pin has a high input impedance, so that if you get your hand near it, while the system is running, the output voltage may swing wildly, and certainly cause the system to reboot, and possibly even damage the system. Therefore I trim away unused pins:
trim ISR pins

Next, I get my soldering iron ready. This is the soldering iron that I purchased for soldering number thirty wire directly to the Kopin Cyberdisplay.
soldering iron
This is the finest tip iron available on the market, but it also has various medium and coarse tips available, suitable for soldering the powertrends ISR. Here I am using the medium size tip on the iron.

So now I begin to solder the wires and capacitors onto the Powertrends ISR:
installing capacitors

I make certain to use all of the pins +5v pins in parallel, and all the grounds in parallel, along with the wires to the power connector. I put filter capacitors on both ends of the wires from the ISR to the power connector. Now I have the completed power supply subsystem:
finished isr+connector
I put banana connectors on the input side, for connection to a 12 volt battery.

Now, before I plug it into my computer, I make sure that the output is really actually 5 volts:
checking voltage
Once I verify that I have connected everything up right (here I found that the voltage was approximately 5.01 volts, so I am happy that I have connected everything up right), I then plug it into the computer to test that it works well with the computer:
testing in wearcomp.
Indeed, it works well with the computer, and the voltage is still approximately 5.00 volts while the computer is booting, and while it is running.

I also tried to measure the current draw on the 5 volt side, using a variety of different kinds of ammeters, and found that whenever I had any ammeter in series with the 5 volts, the computer would not boot (the computer appears to be very sensitive to exact input voltage requirements, etc.). Therefore I installed an ammeter in series with the 12 volt side, and, knowing the power conversion efficiency of the device, am able to calculate the current drain, power consumption, etc..

In order to mount the device inside the case, and to keep the device cool, I used a copper bar:
copper bar:

I had to file down some rough edges:
filing;
filed;

Once filed down, I installed the ISR inside the case, with the copper bar as a means of support, and an excellent heatsink:
installing.

Lastly, there is the matter of the large keyboard interface card, which also has mouse and serial ports, etc.. I decided to make this system be a "dred rig", e.g. one in which wires emerge, with connectors on the end. This reduces size, bulk, without all the connectors sticking out and adding to the bulk. Therefore, after contacting the company, I was able to find out how to bypass this large interface circuitboard.
keyboard connector board

I now have a complete working supercomputer facility in my belly bag. This, I typically operate with an AlphaGrip two handed keyer, a Twiddler one handed keyer, or a home made keyer.

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