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Step 4Putting it together
I ran into a few unexpected things but mostly my board is laid out like my schematic, except
for I left the 330 ohm resistors on the board. I rearranged my three connection points so
that the "ring" of a headphone cord was a common and a negative for the LED's.
This effectively resulted in moving two X's to between the resistors and the LED's,
and one on the Collector of the transistor.
The headphone cord had 30 gage manget wires inside it, which is rather annoying,
but I stripped it by scratching the wires with a sharp blade, and then I knew that
it was off when I was able to tin it by dipping the wire in a hot solderball. Some
headphone cords are better, with coaxial stranded wire pairs. Another option for
the cord is ribbon cable and a "new" headphone plug.
MAKING THE LED CORD:
The negative for both LEDs is the back of the plug. The tip of the plug is positive for one LED
and the thing in between is positive for the other LED. You should be able to test the other
end of the cord to see what part of the plug it connects to. A good headphone cord has an
outer bare coaxial shield that is connected to the common, and you can unzip the end to
place the LEDs apart because both wires have the common, which is negative.
LEDs should be tested with a lithium coin "throwie battery (see Make)" to make sure that
the polarity is normal. MOST LED's have a shorter lead for negative, and that lead also
is recognizable as being L-shaped within the LED, even if the LED has identical length leads
because it was used before and you salvaged it. Some rare weird LEDs don't follow these rules.
I used gray ribbon cable for connecting the switch-pot and the headphone jack,
in this case the LED-glasses jack. It is easy to find on old hard drives, but it
may be nicer and easier if you happen to have color coded ribbon cable laying around.
Taking a picture of the board is hard but I made it really small so it fits in that
case with the battery and the switch-pot and the headphone jack. It fits in
a slot of the black box.
for I left the 330 ohm resistors on the board. I rearranged my three connection points so
that the "ring" of a headphone cord was a common and a negative for the LED's.
This effectively resulted in moving two X's to between the resistors and the LED's,
and one on the Collector of the transistor.
The headphone cord had 30 gage manget wires inside it, which is rather annoying,
but I stripped it by scratching the wires with a sharp blade, and then I knew that
it was off when I was able to tin it by dipping the wire in a hot solderball. Some
headphone cords are better, with coaxial stranded wire pairs. Another option for
the cord is ribbon cable and a "new" headphone plug.
MAKING THE LED CORD:
The negative for both LEDs is the back of the plug. The tip of the plug is positive for one LED
and the thing in between is positive for the other LED. You should be able to test the other
end of the cord to see what part of the plug it connects to. A good headphone cord has an
outer bare coaxial shield that is connected to the common, and you can unzip the end to
place the LEDs apart because both wires have the common, which is negative.
LEDs should be tested with a lithium coin "throwie battery (see Make)" to make sure that
the polarity is normal. MOST LED's have a shorter lead for negative, and that lead also
is recognizable as being L-shaped within the LED, even if the LED has identical length leads
because it was used before and you salvaged it. Some rare weird LEDs don't follow these rules.
I used gray ribbon cable for connecting the switch-pot and the headphone jack,
in this case the LED-glasses jack. It is easy to find on old hard drives, but it
may be nicer and easier if you happen to have color coded ribbon cable laying around.
Taking a picture of the board is hard but I made it really small so it fits in that
case with the battery and the switch-pot and the headphone jack. It fits in
a slot of the black box.
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