Ultra PicoKeyer
27 January 2017 (Firmware V2.2)
Page 16 of 21
Locate pushbutton switches S1 through S4. Install the switches, one
at a time, in the marked locations. Make certain each switch is fully
seated and that the metal base of each switch is straight and flush
with the board. It’s important to get these lined up right so the
pushbuttons will fit properly in the holes of the cabinet end panel.
Install the speed control potentiometer in the location marked
SPEED. Like the pushbutton switches, this part must be inserted
fully
into the PCB so that the bottom of the metal bracket sits firmly
flush against the PCB. Even a slight mis-alignment here can cause
fit problems with the cabinet later, so double check your work. After
you solder it in place, turn the adjusting shaft fully counter-
clockwise.
Install the three stereo jacks in the locations indicated on the
component side of the PCB. Be sure to get them fully seated and
flush against the board. There are plastic pins on the bottom that will
fit into holes in the PCB when they are pushed all the way in. Again,
it’s important to make sure these are properly mounted and straight.
If they’re not lined up right, you will have trouble installing the
board into the plastic cabinet.
C3 is used to limit the amount of audio supplied to the headphone
jack. Install one of the remaining capacitors in location C3. You
may want to leave this unsoldered until you have had a chance to test
it with your headphones or earphones. The
.047 μF capacitor
(marked 473) gives good results with many earphones. If you need
more audio, try the
0.1 μF capacitor
(marked 104). If it’s too loud
even with the .047 μF capacitor, you may need to try a smaller value
such as 0.01 μF (marked 103).
Be careful
while testing this!
Too
much audio can damage your hearing. If you intend to use
earphones or headphones, try it with the earphones or headphones
OUT of your ears first.