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TESTING, CALIBRATION, AND TROUBLESHOOTING

TESTING OF LCD

With no test leads connected to the meter, move the selector switch around the dial. You should obtain the following
readings. A (--) sign may also be present or blinking.

1) DCV Range:

200m

0 0.0

2000m

0 0 0

20

0.0 0

200

0 0.0

1000

0 0 0

2) ACV Range:

200

0 0.0

750

0 0 0

3) DCA,10A Ranges:

200

µ

0 0.0

2000

µ

0 0 0

20m

0.0 0

200m

0 0.0

10A

0.0 0

4) Ohms, Diode and h

FE

Ranges: B indicates blank.

200

1 B B.B

2000

1 B B B

20k

1 B.B B

200k

1 B B.B

2000k

1 B B B

Diode (          )

1 B B B

h

FE

0 0 0

Figure 4-7

PC Board

6mm Screws

Slide Contactor

Rib

Close-up View

Bearings

Battery Compartment

Case Top

Selector Knob

LCD Cover

Summary of Contents for M-1005K

Page 1: ...DIGITAL MULTIMETER KIT MODEL M 1005K Assembly and Instruction Manual Elenco Electronics Inc Copyright 1996 Elenco Electronics Inc REV J Revised 2000 753042...

Page 2: ...ge black yellow gold 163000 1 R25 470k 5 1 4W yellow violet yellow gold 164700 1 R23 510k 5 1 4W green brown yellow gold 165100 1 R24 820k 5 1 4W gray red yellow gold 168200 1 R17 1 2M 5 1 4W brown re...

Page 3: ...Most capacitors will have their actual value printed on them Some capacitors may have their value printed in the following manner Second Digit First Digit Multiplier Tolerance The above value is 10 x...

Page 4: ...ered must be heated sufficiently so that the solder flows freely Apply the solder simultaneously to the component lead and the component pad on the PC board so that good solder flow will occur Be sure...

Page 5: ...te silver green Standard Location R 100 5 1 4W Resistor brown black brown gold see Figure B R21 220k 5 1 4W Resistor red red yellow gold see Figure B Figure C Mount the transistor with the flat side i...

Page 6: ...Figure B R3 90k 5 1 4W Resistor white black black red green see Figure B R2A 117k 1 1 4W Resistor R2B 117k 1 1 4W Resistor R2C 117k 1 1 4W Resistor brown brown violet orange brown see Figure B R1A 27...

Page 7: ...does not carefully slide it through the hole several times in each direction to remove any burrs Do not push on the socket leads or they may be damaged Insert the socket into the PC board holes from...

Page 8: ...oard with two 6mm screws as shown in Figure 4 7 Insert the 25A 250V fuse into the fuse clips Your fuse may be unmarked Peel the backing off of the shield label and place it in the inside of the bottom...

Page 9: ...CV Range 200m 0 0 0 2000m 0 0 0 20 0 0 0 200 0 0 0 1000 0 0 0 2 ACV Range 200 0 0 0 750 0 0 0 3 DCA 10A Ranges 200 0 0 0 2000 0 0 0 20m 0 0 0 200m 0 0 0 10A 0 0 0 4 Ohms Diode and hFE Ranges B indicat...

Page 10: ...f the assembly instructions c Check the values of resistor R10 R13 R26 and potentiometer VR1 DC VOLTS TEST 1 If you have a variable power supply set the supply to about the midpoint of each of the DCV...

Page 11: ...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 te...

Page 12: ...rrent signals are conditioned by the selector switches to produce an output DC voltage with a magnitude between 0 and 199mV If the input signal is 100VDC it is reduced to 100mVDC by selecting a 1000 1...

Page 13: ...number of clock pulses that occur during the read period During autozero a ground reference is applied as an input to the A D converter Under ideal conditions the output of the comparator would also...

Page 14: ...utput 4 LOGIC CONTROL Internal Digital Ground 200 BACKPLANE 21 V TEST V 500 37 26 6 2V 1V Three inverters One inverter shown for clarity 40 39 38 OSC 1 OSC 2 OSC 3 DIGITAL SECTION ANALOG SECTION of 71...

Page 15: ...simplified diagram of the AC voltage measurement function The AC voltage is first rectified and passed through a low pass filter to smooth out the waveform A scaler reduces the voltage to the DC value...

Page 16: ...RCUIT VOLTAGE 2 8V Figure 7 8 RESISTANCE MEASUREMENT Figure 7 7 shows a simplified diagram of the resistance measurement function A simple series circuit is formed by the voltage source a reference re...

Page 17: ...t known set the switch to the highest range 4 Connect the leads across the points to be measured and read the display If the range switch is too high reduce it until a satisfactory reading is obtained...

Page 18: ...ates that the battery should be replaced To replace battery and fuse 250mA 250V remove the 2 screws in the bottom of the case Simply remove the old fuse battery and replace with a new fuse battery QUI...

Page 19: ...22 21 OSC 1 OSC 2 OSC 3 TEST REF HI REF LO REF CAP REF CAP COMMON INPUT HI INPUT LO AUTO ZERO BUFFER INTEGRATOR SUPPLY G TENS C 100 s A 100 s G 100 s BACKPLANE POLARITY MINUS AB 1000 E 100 s F 100 s...

Page 20: ...Elenco Electronics Inc 150 W Carpenter Avenue Wheeling IL 60090 847 541 3800 www elenco com e mail elenco elenco com...

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