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error of 1 percent if it shunts a 10-megohm resistor. Using the following steps, you will be able to
measure dc resistance ONLY:
1. Turn the DET GAIN control to 2.
2. Set the FUNCTION switch to R 1 or R 10.
3. Set L-R-C decade dials to 3.000.
4. Connect the unknown resistor to R-L terminals 1 and 2.
5. Set the GEN-DET switch to INT DC.
6. Adjust the RANGE switch for minimum detector deflection.
7. Adjust L-R-C decade dials for null, turning the DET GAIN control clockwise to increase
sensitivity as necessary.
8. The measured resistance is the product of the L-R-C decade dial setting times the RANGE and
FUNCTION switch settings.
CAPACITANCE MEASUREMENTS
Capacitance is measured in terms of a two-element equivalent circuit consisting of a capacitor in
series with a resistor. The internal ac generator and detector of the model 250DE bridge are tuned to 1
kilohertz. Other frequencies can be used, but an external generator and detector are required. The D and Q
ranges of the bridge can be extended by use of an external rheostat connected to the terminals provided.
The measured capacitance is the product of the L-R-C dial setting times the setting of the RANGE switch.
Using the following steps, you can make a standard capacitance measurement:
1. Turn the DET GAIN control to 1.
2. Set the FUNCTION switch to C, D 0.1 or D 0.01 SERIES.
3. Set L-R-C decade dials to 3.000 and D-Q dial to 0.
4. Connect the unknown capacitor to C terminals 2 and 3.
5. Set the GEN DET switch to INT 1 kHz.
6. Adjust the RANGE SWITCH for minimum detector deflection.
7. Adjust L-R-C decade dials and D-Q dial alternately for a minimum meter deflection, turning the
DET GAIN control clockwise to increase sensitivity as necessary.
8. The measured capacitance is the product of the L-R-C decade dial settings.
9. The measured dissipation factor (D) is the product of the D-Q setting times the FUNCTION
switch setting.
INDUCTANCE MEASUREMENTS
Inductance is measured in terms of a two-element equivalent circuit consisting of an inductance
either in series or in parallel with a resistance. The internal ac generator and detector of the model 250DE
bridge are tuned to 1 kHz. Other frequencies can be used, but like capacitance measurements, an external
