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Final assembly – Elenco Digital Mulitmeter Kit User Manual

Page 11

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RESISTANCE/DIODE TEST

1) Measure a resistor of about half of the full scale value of each resistance range. Compare the kit meter

readings to those from a meter of known accuracy.

2) Measure the voltage drop of a good silicon diode. You should read about 700mV. Power diodes and the base

to emitter junction of power transistors may read less.

If any of these tests fail:

a) Check the values and the soldering of resistors PTC - R2, R20 - R27, and R35.

h

FE

1) Set the range switch to h

FE

and insert a small transistor into the appropriate NPN or PNP holes in the

transistor socket.

2) Read the h

FE

of the transistor. The h

FE

of transistors varies over a wide range, but you will probably get a

reading between 100 and 300.

If this check fails:

a) Check that the transistor socket is aligned according to Figure E.

b) Check the value and soldering of resistors R18 and R19.

FINAL ASSEMBLY

r

Peel the backing off of the shield label and stick it onto the case bottom in the location shown in Figure Pa.

r

Snap the case bottom onto the case top and fasten with the two 10mm screws as shown in Figure P.

Case
Bottom

Screws

Case Top

Figure P

Battery

Case Bottom

Shield Label

Figure Pa