The front panel:
Below are close-ups of the panels. The first one is the one right
below the screen.
This panel is used for the monitor's controls as well as for the
indicators and buttons of the PC. Below are the two panels to the
left and to the right of the screen.
The left panel contains the power switch, headphone output as well as the voltage control for the built-in variable output power supply. The purpose of the variable power supply is to supply power to the microcontroller programmer, or any other device which is connected to the PC. The output of the power supply is available on the back panel. The right panel contains the audio controls. The unit has built-in speakers, which is automatically disconnected if headphones are plugged in. At the top-left is the PC speaker control. The switch switches the physical speaker on or off, while the level control controls how loud the PC speaker is heard over the stereo speakers/headphones. The next level control controls the volume of the stereo speakers. The rightmost level control controls the level of the audio output on the back panel. In the middle is the laser and light controls. Audio may be sent directly to the laser's X and Y servos. The ASSIGN switch selects whether the audio comes directly from the back panel, or if it comes from the output of the sound card. The two SIZE controls controls the amount of audio send to the servos. The MUTE switch is used to mute all the light outputs on the back panel. Below are two auxiliary outputs which, just as with the laser, my be tapped from either the back panel input or the sound card output. The LEVEL controls control the level of the auxiliary outputs on the back panel.
The back panel
Below is a photo of the backside of the PC. There are two connector panels, one for the audio and lights connectors and one for the PC's serial and parallel ports. The box also has two extractor fans, one inside the power supply as well as an additional one.
Below are close-ups of the two connector panels.
The above panel is used for all audio and light connections. The
system has 4 8-channel port outputs. Each of the 4 8-channel ports is
on a DB9 connector. The first 5 bits is also available on a 5 pin DIN
plug. The remaining outputs of the first two ports are used to control
4 strobe light's as well as 2 smoke machines. The Smoke machine ports
also reads in the status of the machine ready indicator. All these
outouts are eiter on or off. The MIDI ports
from the sound card is also available on the backplane. There is also a
MIDI thru port. There are also three connectors (HDM1-3) for my own
in-ear monitoring system. The laser control output is the topmost
connector on the right. Below this is the audio input and outputs.
Below is a photo of the computer connector panel:
The computer connector panel is used for the computer's serial and
parallel ports. There are two parallel ports (LPT1,2) and three serial
ports (COM2-4). COM1 is used internally for the mouse. The output
terminals of the variable voltage PSU is also placed on this panel.
Below are photo's showing the PC in various stages of construction.
The first photo shows the basic frame. I have constructed the frame
using aluminium angle irons (25mm x 25mm x 1.6mm). I used M4 screws to
fasten everything. I have put glue on the nuts which will never be
removed. This is important since if a nut and its washer comes loose,
it might fall on the electronics and cause a short circuit.
The power supply for audio circuits are mounted on the aluminium plate in the center. The smaller transformer is the transformer for the speakers. As can be seen, the aluminium plate was moved to the back of the box. The magnetic fields of the transformers caused interference on the CRT image. Moving the transformers to the back wasn't that effective. In the end I changed to wiring on the transformers so that the two are fed out of phase. Since the two generated magnetic fields now cancels each other, there are no longer any interference on the CRT image. The PCB which can be seen at the bottom right of the second image is the laser controller digital to analogue converter card.
I used hardboard for all the sides of the box. I used thin plywood
to make the odly shaped panels around the monitor and the diskdrives. I
have found that is is very easy to cut plywood with a knife, must
easier than cutting hardboard. I have so far used plywood for several
The old PC
Here are some photos of the first portable PC I build. I have used
it a lot in the field as a portable PC, but since I have the new PC
now, I have disassembled this PC. This one was based around a
486DX2-80. Here the monitor was not build into the box. There is a
space above the stiffy drive to hold the mouse, a mousepad which slides
out, as well as a light to illuminate the keyboard in a dark room.
Here I used wood as construction material, the motherboard was also
directly mounted onto the bottom of the case. Luckily the wooden case
was strong and it didn't flex, which can seriously damage the
motherboard. Below is a photo of the inside of the PC with the
keyboard flap close.
I have glued aluminium foil onto the wood for shielding. The wood made
the box heavy, especially since the wooden frame needed to be strong.
That is the reason why I have decided to use a lightweight aluminium
frame for the new PC, and 3mm thick hardboard for the sides.
Furthermore the motherboard of the new PC is mounted on its own base
plate, which will not flex, even if the frame flexes.