When you complete the
soldering, your decade box should
look something like Figure 6.
Some precision resistors can
only be purchased in minimum
quantities of 100 or 1,000 pieces.
When I designed this decade box, I
made the decision to buy a few
resistors that were as close to the
required value as possible ( 60.4K for
a 60K), rather than purchasing 100
resistors just to get one that is
exactly 60K. If you want a more
accurate response from your resistor
decade box, then you may want to
search the Internet for lower
I hope you enjoy your new tool
for decades! NV
February 2016 27
■ FIGURE 5.
■ FIGURE 6.
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Author’s note: VERIFY ALL RESISTANCE
VALUES BEFORE SOLDERING.
Unfortunately, the company where I
purchased my resistors sent the wrong
resistance value for one resistor. I was
forced to string three resistors together
to make 60K. This made it difficult to fit
in between the other resistors. Also,
don’t bend and cut all the resistors in
this project at the same time. You’ll get
confused as to what resistor value you
have laying on your work bench. This
will force you to get out the ohmmeter
and verify the resistance value –
■ FIGURE 4.