Elenco Electronics M-1006K, Assembly And Instruction Manual

AC VOLTS TEST

To test the ACV ranges, we will need a source of AC voltage. The AC power line is the most convenient.

CAUTION: Be very careful when working with 120VAC. Be sure that the range switch is in the 200 or 750VAC
position before connecting the test leads to 120VAC.

1) Set the range to 200VAC and measure the AC power line. The voltage should be about 120VAC. Compare

the reading to a meter of known accuracy.

2) Set the range to 750VAC and measure the AC power line. The voltage should be about 120VAC. Compare

the reading to a meter of known accuracy.

If either if the above tests fail:

a)   Check the values and the soldering of resistors R1 - R6, R22.

b)   Check that diode D1 is mounted as shown in the assembly instructions.

DC AMPS TEST

1) Set the range switch to 200

µ

A and connect the meter as in Figure J. With R

A

equal to 100k

Ω

the current

should be about 90

µ

A. Compare the reading to a known accurate meter.

2) Set the range switch and R

A

as in the following table. Read the currents shown and compare to a known

accurate meter.

If any of the above tests fail:
a) Check the fuse.
b) Check the value and soldering of resistors R7, R8, and R9.

DC VOLTS TEST

1) If you have a variable power supply, set the supply to about the midpoint of each of the DCV ranges and compare the

kit meter reading to a meter known accuracy.

2) If you do not have a variable power supply, make the following two tests:

a)

Set the range switch to 2000mV and measure the voltage across the 100 ohm resistor of Figure Ia. You should get
about 820mV. Compare the reading to a meter of known accuracy.

b)

Set the range switch to 200mV and measure the voltage across the 100 ohm resistor of Figure Ib. You should get
about 90mV. Compare the reading to a meter of known accuracy.

If any of these tests fail:

a) Recheck the meter

calibration.

b) Check the value and the

soldering of resistors R1-
R6, R12-R17, R21-R24,
and capacitor C3.

-9-

Figure J

Figure Ia

Figure Ib

1k

Ω

10A DC

V

Ω

mA

COM

100

Ω

9V

123

10k

Ω

10A DC

V

Ω

mA

COM

100

Ω

9V

123

Range Switch

R

A

Current (approx.)

2000

µ

A

10k

Ω

900

µ

A

20mA

1k

Ω

9mA

200mA

470

Ω

19mA

V

Ω

mA

COM

10A DC

123

Accurate

Meter

R

A

9V