As shown above, you should have the following (clockwise from top-left)
• One Decade Resistance Box PCB
• Nine 10
Ω
Resistors (Brown - Black - Black - Gold - Brown)
• Nine 100
Ω
Resistors (Brown - Black - Black - Black - Brown)
• Nine 1000
Ω
Resistors (Brown - Black - Black - Brown - Brown)
• Nine 100K
Ω
Resistors (Brown - Black - Black - Orange - Brown)
• Nine 10K
Ω
Resistors (Brown - Black - Black - Red - Brown)
• One red banana jack
• One black banana jack
• Five 1-pole 10-position rotary switches, each with a dress washer
and hex nut
Electronic Assembly
For the most part, the assembly of the decade resistance PCB is straight
forward. We’ll cover a few extra tips and tricks as we go along.
The first thing to note is that the PCB has definite top and bottom sides.
The components are placed on the top of the board, which is marked with
symbols for each component - tick marks for the resistors, and oblong
outlines for the rotary switches. The components are soldered to the back
of the board. The copper solder pads are only exposed on the back side - if
you’re having trouble getting the solder to stick, doublecheck that you’re
working on the correct side.
Soldering Resistors
Unlike many other soldering kits where the resistors lie flat on the PCB, the
resistors on the decade resistance will be installed in a “standing up”
orientation. This saves space on the PCB, and is commonly used in
devices like guitar pedals and transistor radios.
To fit the resistor to the board, bend one lead sharply at the end of the
body, doubling back 180°, so the overall result looks like a hairpin.
Then insert the resistor into the board, and splay the leads so they hold it in
place while you solder.
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