-9-
RESISTOR READING EXERCISE
(1) yellow-black-black-black-brown
(3) brown-red-violet-red-brown
(5) brown-black-black-black-brown
(7) white-black-black-yellow-green
(9) brown-black-black-orange-green
(11) gray-white-black-black-brown
(2) white-black-black-red-green
(4) green-black-green-brown-green
(6) brown-green-gray-orange-brown
(8) white-black-black-silver-green
(10) orange-white-red-red-brown
(12) brown-brown-black-red-brown
Answer
s to Resistor Reading Exer
cise:
1) 400
Ω
+1%;
2) 90k
Ω
+.5%;
3) 12.7k
Ω
+1%;
4) 5.05k
Ω
+.5%;
5) 100
Ω
+1%;
6) 158k
Ω
+1%;
7) 9M
Ω
+.5%;
8) 9
Ω
+.5%;
9) 100k
Ω
+.5%;
10) 39.2k
Ω
+1%;
11) 890
Ω
+1%;
12) 11k
Ω
+1%;
Before starting assembly of your digital multimeter
project, you should be thoroughly familiar with the 5
band color code system.
Many of the resistor
values will be identified by color bands and it is easy
to mistake their value if you read the colors
incorrectly or read the value from the wrong end.
Do the following exercise in resistor values. Place
your answer in the box beneath the resistor.
Answers are on the bottom of this page.
Table 1
-26-
REINSTALLATION OF THE RANGE SELECTOR KNOB
If you removed the range selector knob for troubleshooting,
then follow the instructions below to reinstall it.
Place the PC board over the range selector knob and
fasten the knob to the PC board with a M2.3 x 8 screw.
CAUTION:
Do not overtighten the screw. The knob
should be snug, but not loose. Turn back the M2.3 x 8
screw 1/2 turn. Slip the two shims under the knob (see
Figure L). If they do not slip in, turn back the screw
another 1/4 turn. Tighten the screw just enough so that
the shims can be pulled out. You should now have the
proper tension to hold the knob and contacts in place and
rotate the knob to the desired positions.
USING THE DIGITAL MULTIMETER
MEASURED
RANGE SETTING
RESISTANCE
200
Ω
2k
Ω
20k
Ω
200k
Ω
2M
Ω
20M
Ω
00.1
.000
0.00
00.0
.000
0.00
INFINITY
1 .
1.
1 .
1 .
1.
1 .
47
Ω
52.1
.052
0.05
00.0
.000
0.00
270
Ω
1 .
.267
0.26
00.2
.000
0.00
10k
Ω
1 .
1.
10.18
10.2
.010
0.01
47k
Ω
1 .
1.
1 .
52.7
.052
0.05
470k
Ω
1 .
1.
1 .
1 .
.472
0.47
2.2M
Ω
1 .
1.
1 .
1 .
1.
2.12
SHORT
(LEADS TOUCHING)
*
*
RESISTANCE OF TEST LEADS
Table 2
Bottom View of Selector Knob
& Slide Contacts
Slide Contact
Shim
Shim
Figure L
MEASURED
VOLTAGE
200mV
2V
20V
200V
1000V
117VAC
1 .
1.
1 .
117.0
117
100VDC
1 .
1.
1 .
100.0
100
Familiarize yourself with your new digital meter by
taking readings of known resistances and voltages.
You will find that the readings will not be as accurate
on certain ranges for a given measurement. For
example, when measuring a low resistance on a
high range, the reading will show a short 0.00.
When measuring a high resistance on a low range,
the reading will show infinity 1.
Likewise, it is
important to use the correct range when measuring
voltages.
Table 1 shows an example of the readouts for
different values of resistance. Table 2 shows an
example of the readouts for 117VAC and 100VDC.
The shaded area indicates the most accurate range.
It must be remembered that the readings will shift
slightly when switching to a different range.
