Parts Identification - Elenco Electronics M-2665K Assembly And Instruction Manual

Amps Section
1. 200mA scale not working:
A. Check fuse.
B. Measure across (A) terminal and (COM)
terminal for 1Ω (set meter in 200mA).
1. Lower or higher than 1Ω, Check R13.
2. 20mA scale not working:
A. Check fuse.
B. Measure between (A) terminal and
(COM) for 10Ω (set meter in 20mA).
1. Lower or higher than 10Ω, check R12
and R13.
Capacitance Section
1. Place .001µF cap in the socket and check pin 7
and pin 8 of U4 with a scope (meter set to 2N).
Pin 7 370Hz - 400Hz .12Vpp.
Pin 14 370Hz - 400Hz .3Vpp.
A. No signal at pin 14.
1. Check D3, D4 and shorts.
B. No signal at pin 7 but present at pin 1.
1. Check D5 and D6.
h Section
FE
1. Check for shorts on socket pins.
2. Measure across B terminal to COM terminal for
251kΩ.
A. Lower or higher than 251kΩ; Check R14
and R15.
Decimal Point Section
1. Displays two decimal points.
A. Shorted output on U2.
2. No decimal points displayed.
A. Check U2 325.
Diode
1. Measure voltage across V OHM and COM
terminal (set in diode mode) = 1.3V.
A. Low voltage, check R26.
Battery Low Indicator
1. Not working.
A. Check ZD1, R19 and U2.
-25-
SECTION A
Meter Display Circuit
PARTS LIST - SECTION A
If any parts are missing or damaged, see instructor or bookstore. DO NOT contact your place of purchase as they will not
be able to help you.
Contact Elenco™ Electronics (address/phone/e-mail is at the back of this manual) for additional assistance, if needed.
Qty. Symbol Description
1 R24 56kΩ 5% 1/4W
1 R19 100kΩ 5% 1/4W
1 R20 110kΩ 5% 1/4W
6 R16, 17, 18, 21, 22, 23 1MΩ 5% 1/4W
Note: Resistor tolerance (last band) of 5-band resistors may be green instead of brown.
Qty. Symbol Value
1 C2 100pF (101)
1 C3 .047µF (473)
1 C4 .1µF (104)
2 C5, C6 .22µF (224)
SEMICONDUCTORS
Qty. Symbol Value
1 ZD 1N5232/1N752
1 U2 4030/4070
1 U1 7106R
Qty. Description
1 Liquid Crystal Display (LCD)
1 Zebra
1 PC Board 516000A
1 Solder Roll
1 Battery Snap (BAT)
1 Battery
1 LCD Window Plate 621002A
1 Range Selector Knob
*
1 Bushing
*
* Parts installed on PC board already.

PARTS IDENTIFICATION

Resistor Integrated Circuit
Diode
Socket
Capacitor Battery Snap
Ceramic Mylar
RESISTORS
Color Code
green-blue-orange-gold
brown-black-yellow-gold
brown-brown-yellow-gold
brown-black-green-gold
CAPACITORS
Description
Ceramic Capacitor
Mylar Capacitor
Mylar Capacitor
Mylar Capacitor
Description
Zener Diode
Integrated Circuit
Integrated Circuit
MISCELLANEOUS
Part # Qty. Description
35114A 1 LCD Stopper
500000 1 LCD Housing
2 M2.3 x 6 Screw
551135 1 M2.3 x 8 Screw
*
590098 1 IC Socket 40-Pin
590009 6 Slide Contact
*
1 Top Plate (A)
622003 2 Shims (see page 26)
624004
Top Plate (A) Liquid Crystal Display (LCD)
LCD Housing
LCD Window
Plate
LCD
LCD Stopper
Zebra
-10-
Part #
155600
161000
161100
171000
Part #
221017
244717
251017
252217
Part #
315232
334030
337106R
Part #
629005
629007
642360
642430
664040
680016
724001A
780006