Heathkit IM 1202 Manual

Page 2

Page 36

Refer to Pictorial 4-6 and prepare the meter test leads.

( /) Remove 1/2 insulation from each end of the large red
wire.

(l/ Install a test probe on one end of the large red wire as
follows:

1. Unscrew the insulator and the cap nut from the probe
tip and insert the wire through the smaller hole in the
insulator.

2. Twist the fine wires together and insert them through
the hole in the probe. Then form the wires around the
probe and screw the cap nut over them. Screw the
insulator back on the probe.

(fl. Place the other end of the large red wire through the
smaller hole of the red plug insulator.

( Il/ Twist the fine wires together and insert the wires
through a banana plug. Form the wires clockwise and
screw the insulator on the banana plug as shown.

(V) In a similar manner, install a banana plug and black
insulator on the large black test wire.

(4 Install the alligator clip on the free end of the large
black wire. Insert the end of the black wire through
the smaller end of the alligator clip insulator. Twist
the fine wires together and insert them into the
alligator clip (8-1). Slip the alligator clip insulator
down over the alligator clip after the clip has cooled.

This completes the "Step-by-Step Assembly " section of the
Manual. The cabinet will be installed later. Carefully inspect
the Multimeter and all circuit boards for loose or unsoldered
wires, and cold solder connections. Remove any wire
clippings or solder splashes that may be lodged in the wiring.

3/41 %011 27
LLI/QA i .l l I I l l

HEATI-IKIT 6

TEST
PROBF

fl

LARGE CAP
j RED PROBE
INSULAIOR W'RE /
y
WW
/

(If 4
\(

DD; :Q\PLUG
X? if \
PIUG RDQ

INSULATOR\ 3W):
LARGE/j)
WIRE
ALLIGATOR
CLIP

ALLIGATOR ALICIESIAJOR

CLIP K SOIDER '
INSULATOR LARGE

WIRE

PICTORIAL 4-6

Securely hold the Multimeter and shake it to be sure all
clippings are removed. Then proceed with the Tests and
Calibration" section of the Manual.

NOTE: Save any parts remaining; they may be used later.

3 4H 5 611

TESTS AND CALIBRATION

In this section of the Manual you will test and calibrate your
lM-1202 Digital Multimeter. If at any time you do not
obtain the results indicated, refer to the In Case of
Difficulty section on Page 45. Locate and repair any
problem before you continue with the calibration.

OSCILLATOR
ADJUSTN

FUNCTION

SWITCH RANGE
SWITCH

POLARITY

SWITCH\ >INPUT
JACKS

Figure 2

Figure 2 shows the front switches and input jacks of your
Multimeter. Figure 3 (fold-out from Page 36) shows the
remaining controls and test points. Carefully study Figures 2
and 3 and identify the function of each switch, control, and
input.

( ) Refer to Figure 4 and insert all except approximately
3/8" of the alignment tool blade into the small end of
the nut starter.

HEATHKITG

APPROX.

/ .

ALIGNMENT TOOL figure 4
BLADE

( ) Use this alignment tool to set all nine rear controls and
the OSC ADJ control to their centers of rotation (slots
vertical).

( ) Set the front panel switches to the following positions.

Function switch: OFF.
Range switch: 2.
Polarity switch: +.

WARNING: When the line cord is connected to an AC
outlet, AC voltage will be present at several places. These
areas are shown in boxed in area in the Circuit Board
Voltage Charts" (on Page 61), and in Figure 3 (fold-out
from Page 36)

( I Plug the line cord into an AC outlet.

( ) Turn the Function switch to the DCV position and
allow the unit to stabilize for at least 30 minutes.
NOTE: The +" polarity lamp, and the two right-hand
digits (displaying any number) and the decimal point
to the left of the left digit should all be lit. No other
lamp shouldbe lit.

( ) Use the alignment tool and turn the ZERO ADJ
control until the readout is M; Then slowly turn the
control until the readout just changes toga Nothing
should be plugged into the input jacks at this time.
The threshold should rock between .01 and .00.

( ) Plug the red test lead into the red V input jack.

37

Page 7

Page 42

DC VOL'I

CAUTION:
greater tha
result in da

1. Set 1
range

2. Set ti

3. Plug
readi
highe
exist:
switc
table

-
l
l

RANGE

-

(200 Q)

20
200
2 k

W A VE F O R M S
Waveforms as displayed on Tektronix Model 547 with type
1A4 4-Channel Amplifier. Line sync.
OSCI LLOSCOPE INPUT
TEST Vertical: Horizontal: COUP- Waveforms POSSIBLE CAUSE OF IMPROPER WAVEFORM
POINT Volts/cm m sec LING (DC zero-volt reference point indicated by arrowhead)
1 D16, Anode 200 2 DC 1. Diode D16.
2. No voltage from transformer.
2 ICE, pin 5 1 2 AC 1. Resistor R219.
(2 VDC
input) 2. lC8.
3. Solder bridge.
3 IC8, pins 2 2 DC 1. Pin 4 not held high (+5 VDC).
6 and 9
2. ICE.
3. Solder bridge.
4 ICB, pin 8 2 2 DC 1. Pin 10 not held high (+5 VDC).
2. Pin 8 of |C2 grounded.
3. lC8.
4. Solder bridge.
5 ICE, pin 1 2 2 DC 1. Capacitor 0205 or C206.
2. Resistor R217.
3. Solder bridge.
6 lC8, pins 2 2 DC 1. Pin 2 not held high (+5 VDC).
3 and 12
2. |C8.

K2. 5