Heathkit IM 2202 Schematic

Page 1

Assembly
and
Operation

of the
HEATHKIT=.,,; .

PORTABLE DIGITAL MULTIMETER

MODEL lM-2202

' A A!

Comm @1975 H E AT H C O M PA N Y

Heath Company

Aurighrsreserved BENTON HARBOR, MICHIGAN 4'90 2 2 Printed in USA.

Page 2

'----------|-----------------------------------------------------------------------------------w
I q
-- I m ADJ. DISPLAY CIRCUIT BOARD T
r--------- '---------------------------¢----------------------------------------------1l : \ 940; 02 :
l I ' 1000 6570 +Tzv
I : FB W107" +12v :
SW1 SW2 $w3 SW4 : HIGH-2- AC TO DC CONVERTER m | I _. > O Q , Tosw 5 1 I
BUFFER +12v +12V sz AND FILTER 10K I ' R4 Hug: I
O 0 T I S. . 11:" : A Wfai * T33: 33:: 53:3: :
I "1 r5 ILL; r-( - °
A gig B A 3': B I 0,0, 9:07 moo I c104 5W1 F : I -+- * * :
SCHEMATIC OF THE . ® : 56433: IOOK* IOOK* 7.7,; 312%: __CI0P6 I PIP-G- TOK ADJ. HTO EJ T0 EK HTO EL l
h 6) ' ® | 0 0 ® ® I ' an RN AC 0 v: I L- '
HEATHKIT o , , I I 0102 __ 31°42 0 v I I SW5A V402 T
IM 2202 C alg DA | 08 A 103 Cal 0 D ' 9/04 was . Mt . DC/fl ® . I W - - - - |
' 0 I © | C9) © '63) O O : 0919'; 995511-0103 | : O AN3 AN2 ANI |
PORTABLE DIGITAL @ I a'% at: G) : m0": - o 21%), 156-09 2:613 €81 : : cl _ :
C D C D 47 I - - I
MULTIMETER E g : car: 0 | ® 9 I E: BF I T/zw Egg: @1311: \ €20! 22:60 6 +1 I: § [$7. 0 4V1}. : : {8) A A |
I M © I : >l< \ AE L1. 0104 T v m I | B F B F B I
00* w 6 E ,_ _ 1: 500 I I I
I 1&9 r5}? ' uflAF 55 89 1 | FA G G I
I DC/n /0 LOCK-1 ' "a" a" 1 ' AC I ' T- 5 8" - - I
A I I 1 V 9212 I CAL I I l
C MA : :_"I_ 3130; «95,09 23300 +*' cmg a I500 :OlaK : I C E, 'C E I [C :
t- 11 x! 331.1 '
FUNCTION SWITCHES : ®.«_ . N ; I/zw 1'2. I : P-@ D D '
(VTEWEO FROM COMPONENT SIDE) A V | . _ A _ A I
r------------------l-un-----------II-4 fly-J +5V 13ng "2V gnfi | I .-__@ DP DP DP :
NOTES: I i * ' Ii?" 33; : T 0 $1 ASA '
I F 01 SW3C SW2A I 1+ + : I #rmm :
1. RESISTORS ARE 1/4 WATT , 5% UNLESS OTHERWISE INDICATED. ! 31. 0 v/n c/n, £25K? 3'2 :: cm ' IF» 0 P I; OH; ETD P TITO D p d '
mA (:FfiWJ >> 9 g 0 15. -}i 2.2% +12v4-BA- F0 +12v l
2. RESISTORS WITH AN ASTERISKWTARE 10%. : MA AC V y : I l ABCDEFG KA ABCEEEE 5:4
3. ALL 5% AND 10% RESISTORS ARE CARBON COMPOSITION I SW4C SW20 ' 5.: >
EXCEPT R1. I $W3A PW 09h ® : I l l _ Agedak :
1 I _ . _ _ ' _
4. ALL CAPACITORS SHOWN IN DECIMAL ARE OF. C @ :3 0 v/n é) M AC H g g I I To r0 To To? 470 H W PM CV :
5. ** INDTCATES PARTS FROM 960. I V F102 mA ' 9 W 3 BD EV AN4 AN3AN2AN1 V TOA TOB TOC TOD TOE TOF TOG :
6 *** INDICATES PARTS FROM 100 1631 v/n @JlE-o-EEA E 1 as AC 0 VM To 202 V V T T 37 T T 1 T f f f ' * *
- ' - ' ] T
i IT ; DC/Q f S L----IEY --------a EX ------ER -E;}l---------{ET.-[EH EJ EKifiL FC EEEUo---- EA-----IEB--------EC-~------ED--------EE.------IV$+-------EGIJ X 0
7. **** INDICATES PARTS FROM 100-1643. I l" _ AW 1 IX 3me IL
I I 9223 77 I .__________fi _ (W M... _\ K-
8. L. N. IN D' CATES LOW ' NOT SE RES 1 STORS : $110203 swl D L-- ___ _ : r- DC: -----------_--ICU CK ---LE:}---------fl---------ti-----@- cfln-[CL CM CNIE; C DJ fig-----CAL-------E:B]-------- CC -------ICD------- cg--------CF -------I CG.1--ocR.-------
9. V 1NDICATES LOW-NOISE GROUND. I L,N_ SHIELD nm* __® ; __ I . . . J .
|"'"""""""" J2 I 0 AC SW28 SW4}? * I : +12v +l2V +170v ' : :
10. lNDlCATES WIRE CONNECTIONS TO THE LOOP END I -= V I I
| SWIA 0c. 29 ® | I __ I
11. :l INDICATES A LETTERED HOLE ON A CIRCUIT BOARD. E AC - 3 W {ERA/MSW: : 1 i I [- : I HLL'LSRTM ) 3:535: 0203 372333 0207 R2710 fig; V :
ocn 1 L4 \PI36 | ' 9202 ' 9 A1- I
12. ww INDICATES WIREWOUND. : / ® M LN. AC ._,' [3-0. 20.096 W av : : 120K (9 0217 c :
I AS - I I I
I , 1 AR] I ' 9 l
SW5 I T- AV swso 5 V ' : b I
' .7 _-

THE FOLLOWING DC VOLTAGES WERE MEASURED USTNG A HIGH OFF 0 :1 £951: 37: 532;? RACHI 20 , ® : : OHMME TER 9 +170v :
IMPEDANCE {IOMQ OR GREATER) VOLTMETER FROM THE MEASUREMENT #10000 :1 W J H H OH O \ \ IO : l CURR E NT 9253 S '
POINT TO THE ICOMMONT INPUT JACK. VOLTAGES MAY VARY t 20%. MA ,000 I . To 0 \__/ Q g : SOURC E 1500 :

10 O T I O :33 £333... :32? ; » swsc @4 I : z: '12: :
- WAVEFORMS USING BATT POSITION; SEE PAGE 107. ._ 10 I I, Q) m 2w 0 O 8,.0 ' I 22K 22K l
v/UA [000 :~ O ** ** _@ .// $1 9220: 9257: l
"" 18K
__ - _ SP1 s I
O DC VOLTAGES FOR ANY INPUT IN 100mV POSITION. moo T AP 0 30:7 . O a F I I H .15.: :
_ "" 04 «.9205
*- DC VOLTAGES IN IODMV POSITION USING +PT AS INPUT; :1 IKO : O at: SW? 0 O : : 132% 2 32,575 SEGM ENT :
I: 1 o
VOLTAGES WILL BE DIFFERENT FOR DIFFERENT INPUTS. 8 : 8 5:36", 15-50310; I : $ I
IOOK H I I
I
_ I I V I
*-*DC VOLTAGES IN lOOMV POSITION USING -PT AS INPUT; _1000K O : O Icm TR, 0 Q We [1?va. -. 2 I I I
VOLTAGES WILL BE DIFFERENT FOR DIFFERENT INPUTS. BATT O : O .m .005 $10;* -@ O O ' ff. DIG IT DRIVERS :
390 I I I
I *
GREEN VOLTAGES DURING BATTERY CHARGING. EXPOSED LINE I V T __m Bl; 1 :
VOLTAGE IS PRESENT -- USE EXTREME CAUTION. : I _...~ I I I
I 0106 I :1; C" * * +12v :
: 56-93 [:H E / .® +0 .® m :
: +5v -12v : DD JII / +12v :
SW5A swsa I 1 1" I cy * * :
FRONT VIEW FRONT VIEW : r-----o AH -- BB ---II-------------------------------J IDA :
I
: : H l +5v + CURREN T :
: INPUT CIRCUIT BOARD ' T" Ev CE] 92 - +5v 1900 19K 190K IeM @ P3 SOU RCE I
l 0229 .5 I
L--------------------------------u---------1 I : v ' l/2W @ SOURCE T.P. T.P, T'P' T'P' DIGITS I
I +5V -12v . (3 c 'N or 9-0 I
I I ? I
' I ' . ' ® 9293 $9294 9295 9296 EV |
: I : 1 AC + + 1900 :I9K 190K 1.8M 1 9258 :
I REF. 4L **** **** **** **** .
I : Iggy: EAST-O E) 221307 b" C273" "C2T9 ZERO 419'2K :
| l1/2Ws. L 29292 M 47M ~01 9257 I)-N! I
| I ' I - R289 .500 :7 V V . ,.
F1 I : | * $20K é 50K 9259 -Tav :
.125 A (3120 VAC *** m : *** : : 511-4. :
.002 A 240 VAC * I ~12»; ._
an I 0205
TI 7W,ww ! I I 157-65 02l6 @ :
m 0 m AL AM OK c2129 57-27 ~170v :
JUMPERS : 31:5 _-@I--.O T i L201 c}; K 0 SOURCE l
G) SWSH \ 3 )120V I ' ! 0215 :: C23) :
2:4 E AT 3.: 57-27 .02 +12v I
0 --T---* - : :3: TP : = v 1 .® :3 :
_1 *** O I I I
7WITH/O @ ® 2I3}240v I I SOURCE I
JUMPER L E 31:: I O SWSH I : 0205 547-32: 03 (53 ® {1133): I
'0 ® G) G) @ SWSF VIEW FROM 5-2v I O I I 30 +170v *** :
COMPONENT 05:63:00 OM- l : Q : : ' I 0 SOURCE €232 1.9V T.P. I
> I I C226 7 --+ 05 '
0 ® @ SWSE SIDE I @ : 8 : I ' 2'2 4 H 0217 84:18; I
C? : ' : I i + T.P. I
.02 I O : l §§f3__ *** £307 '
SW50 ISOOV O | .. 22000 I
A.Y 1:2 or g *** I
7ng " -.~ - I %
O 6) ® @ 5W T WEE: 117 T2233: :
J NOISE l I
o : GROUND l : 9290» V V * 42* I
l + _ I
L-------------------J ' :T: T.P. I
: C233 S 309 I
I 4w 10218 he; lNTEGRATOR/COMPARATOR 1 :
I
I *** R37, :
I 110K I
I L*** -12v I
' SOURCE l
' I
: AC-DC CONVERTER POWER SUPPLIES LOGIC CIRCUIT BOARD I
I
I

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