Elenco Electronics M-2665K, Сборка и инструкция по эксплуатации

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-10-
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.
RESISTORS
Qty. Symbol Description Color Code Part #
1 R24 56k
Ω
5% 1/4W green-blue-orange-gold 155600
1 R19 100k
Ω
5% 1/4W brown-black-yellow-gold 161000
1 R20 110k
Ω
5% 1/4W brown-brown-yellow-gold 161100
6 R16, 17, 18, 21, 22, 23 1M
Ω
5% 1/4W brown-black-green-gold 171000
Note: Resistor tolerance (last band) of 5-band resistors may be green instead of brown.
CAPACITORS
Qty. Symbol Value Description Part #
1 C2 100pF (101) Ceramic Capacitor 221017
1 C3 .047
µ
F (473) Mylar Capacitor 244717
1 C4 .1
µ
F (104) Mylar Capacitor 251017
2 C5, C6 .22
µ
F (224) Mylar Capacitor 252217
SEMICONDUCTORS
Qty. Symbol Value Description Part #
1 ZD 1N5232/1N752 Zener Diode 315232
1 U2 4030/4070 Integrated Circuit 334030
1 U1 7106R Integrated Circuit 337106R
MISCELLANEOUS
SECTION A
Meter Display Circuit
Resistor
PARTS IDENTIFICATION
Capacitor
Ceramic Mylar
Diode
Integrated Circuit
Socket
Liquid Crystal Display (LCD)
*
*
* Parts installed on PC board already.
Qty. Description Part #
1 Liquid Crystal Display (LCD) 35114A
1 Zebra 500000
1 PC Board 516000A
1 Solder Roll 551135
1 Battery Snap (BAT) 590098
1 Battery 590009
1 LCD Window Plate 621002A
1 Range Selector Knob 622003
1 Bushing 624004
Qty. Description Part #
1 LCD Stopper 629005
1 LCD Housing 629007
2 M2.3 x 6 Screw 642360
1 M2.3 x 8 Screw 642430
1 IC Socket 40-Pin 664040
6 Slide Contact 680016
1 Top Plate (A) 724001A
2 Shims (see page 26) 780006
*
*
Battery Snap
Top Plate (A)
LCD Housing
LCD
LCD Stopper
Zebra
LCD Window
Plate
-25-
Amps Section
1. 200mA scale not working:
A. Check fuse.
B. Measure across (A) terminal and (COM)
terminal for 1
Ω
(set meter in 200mA).
1. Lower or higher than 1
Ω
, Check R13.
2. 20mA scale not working:
A. Check fuse.
B. Measure between (A) terminal and
(COM) for 10
Ω
(set meter in 20mA).
1. Lower or higher than 10
Ω
, check R12
and R13.
Capacitance Section
1. Place .001
µ
F 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
FE
Section
1. Check for shorts on socket pins.
2. Measure across B terminal to COM terminal for
251k
Ω
.
A. Lower or higher than 251k
Ω
; 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.