Make Electronics

Experiencing Electricity 3

Shopping List: Experiments 1 Through 5

On a manual-ranging meter, you select the range, and if the source that

you are measuring is outside of that range, the meter tells you that you

made an error. I prefer this. I also get impatient with the time it takes for

the autoranging feature to figure out the appropriate range each time I

make a measurement. But it’s a matter of personal preference. See Figures

1-5 through 1-7 for some examples of multimeters.

Figure 1-5. You can see by the wear and
tear that this is my own favorite meter.
It has all the necessary basic features
and can also measure capacitance (the
F section, for Farads). It can also check
transistors. You have to choose the ranges
manually.

Figure 1-6. Mid-priced RadioShack meter,

which has the basic features; however,

the dual purpose for each dial position,

selected with the SELECT button, may be

confusing. This is an autoranging meter.

Figure 1-7. An autoranging meter from

Extech offers basic functions, plus a tem-

perature probe, which may be useful to

check whether components such as power

supplies are running unduly hot.

Supplies

Batteries
9-volt battery. Quantity: 1.
AA batteries, 1.5 volts each. Quantity: 6.
The batteries should be disposable alkaline, the cheapest available, be-
cause we may destroy some of them. You should absolutely not use re-
chargeable batteries in Experiments 1 and 2.

Battery holders and connectors
Snap connector for 9-volt battery, with wires attached (Figure 1-8).
Quantity: 1. RadioShack part number 270-325 or similar. Any snap con-
nector that has wires attached will do.
Battery holder for single AA cell, with wires attached (Figure 1-9). Quan-
tity: 1. RadioShack part number 270-401 or Mouser.com catalog number
12BH410-GR, or similar; any single-battery holder that has thin wires at-
tached will do.

Figure 1-8. Snap connector for a 9-volt

battery.

Figure 1-9. Single AA-sized battery carrier

with wires.