Heathkit AS 2A Assembly Manual

Page 1

PRICE 31.00

H E AT H K I T®
ASSEMBLY MANUAL

0

a H EATH K IT"
AV .bawzum

ACOUSTIC SUSPENSION
SPEAKER SYSTEM

MODEL AB-BA

Page 2

RESISTOR AND CAPACITOR COLOR CODES

RESISTORS

The colored bands around thebody of acolor coded resistor rep-
resent its value in ohms. These colored bands are grouped
toward one end of the resistor body. Starting with this end
of the resistor, the first band represents the first digit of
the resistance value; the second band represents the second
digit; the third band represents the number by which the first
two digits are multiplied. A fourth band of gold or silver rep-
resents a tolerance of s5% or 210% respectively. The absence
of a fourth band indicates a tolerance of i20%.

CODE

COLOR IST DIGIT 2ND DIGIT MULTIPLIER
BLACK 0 o I
BROWN I I I0
RED 2 2 too
ORANGE 3 3 Loco
YELLOW 4 4 Idooo
GREEN 5 s loo.ooo
BLUE 6 a Iooo.ooo
VIOLET 7 1 I0.ooo.000
GRAY a e Ioo.ooo.000
WHITE 9 9 - Looo.ooo.ooo
GOLD - - .I
SILVER - - .OI
_ TOLERANCE
, GOLD :57.

SILVER tIO 7.
NO BAND 2202-

The physical size of a composition resistor is related to its
wattage rating. Size increases progressively as the wattage
rating is increased. The diameters of 1/2 watt, lwatt and
2 watt resistors are approximately 1/8, 1/4 and 5/16",
respectively.

The color code chart and examples which follow provide the
information required to identify color coded resistors.

EXAMPLES
-YELLOW-4-
47 x mm
VlOLET-7-} (OR 47K0)

I-ORANGE-LOOO-
WV; SILVER = TOLERANCE

t I070
-RED-2

- RED-2____ 22 x Ioo,ooo
I-GREEN-IOOQOO (OR 2.2 MEG.)

(-\NO BAND -TOLERANCE
%= 220%

CAPACITORS

Generally, only mica and tubular ceramic capacitors, used
in modern equipment, are color coded. The color codes differ
somewhat among capacitor manufacturers, however the codes

MICA
CODE EXAMPLE
COLOR IsTDIGIT 2~nDIGIT MULTIPLIER TOLERW
2 'I X IOO
\ I
suck 7 0 ~- 0 v; I :20 V
own - I g I -I I0 _ RED IOL RED
RED I- z 7 2 - I00 2 2
ORANGE s - a I000 : a
ELLOW 4 7 4 IQOOO -
GREEN 5 -4 I. - 2 5
w: I - I - -
VIOLET 1 -~ 7 _ _
GRAY n -r- n - -
NHITE | - f - -
sou: - -I- - _| _
SILVER - - - .oI : Io
CNAMCTERISTIC

ossERvE
DIRECTION OF
ARROvI

2,700uut : 5 7.
OR .0027 MN

WHLOR

out. DOT CHARACTERISTIC-
INbIcATEs
I1ch

5:: NOTE I BELOW

(VALUE IN nut-5E: NOT: a BELOW)

shown below apply to practically all of the mica and tubular
ceramic capacitors that are in common use. These codes com-
ply with EIA (Electronics Industries Association) Standards.

TUBULAR CERAMIC
Place the group of rings or dots to the left and read from left
to right.

CODE EXAMPLE
COLOR 5T DIGIT 2m: DIGIT MULTIPLIER TOLIR. We
on: mu m

c i a , :20 :20

I I am iI

2 2 - :z

3 a - 12.5

4 A _ _

5 s 20.: x5

I s _ _

7 7 - _

a a £0.25 -

9 a 3 Lo

2|
/ ORG ORG ELK am

I . .
TEMPERATURE 3 z x I 15-1.
cur-wagg-

SEE D
BELOW 33uul' 25%

TEMPERATURE
COEFFICIENT-

SEE NOTE 2
nELow. \

(VALUE IN nut-5E: NOTE a snow)

NOTES:

1. The characteristic of a mica capacitor is the temper-
ature coefficient, drift capacitance and insulation resistance.
This information is not usually needed to identify a capacitor
but, if desired, it can be obtained by referring to EIA Stand-
ard, RS-153 (3 Standard of Electronic Industries Association.)

2. The temperature coefficient of a capacitor is the predict-
able change in capacitance with temperature change and is

expressed in parts per million per degree centlgrade. Refer
to EIA Standard, Its-198 (a Standard 01 Electronic Industries
Association.)

3. The farad is the basic unit of capacitance, however cap-
acitor values are generally expressed in terms of Mid (micro-
farad, .OOOOOI farad) and not (micro-micro-farad, .000001

Md); therefore, 1,000 on! = .001 ufd, 1,000,000 out: lufd.

USING A PLASTIC NUT STARTER

A plastic nut starter offers a convenient method

(3-48 and 6-32). When the correct end is pushed
down over a nut, the pliable tool conforms to the
shape of the nut and the nut is gently held while it
is being picked up and started on the screw. The
tool should only be used to start the nut.

of starting the most used sizes: 3/16 and 1/4 62

Assembly
and

Operation

AC 0 U STI C
SUSPENSION
SPEAKER SYSTEM

MODEL AS-2A

HEATH COMPANY,

BENTON HARBOR.
MICHIGAN

a subsid/a/y of

III-m
DAYSTROM, INCORPORATED

TABLE OF CONTENTS

Specifications. . . . . . . .

Introduction

Unpacking Instructions. , . . . . . . , _ , . . . _ 4

Parts List. . . . .. .

Cabinet Finishing Notes. .

Proper Soldering Techniques. . . . . . . . . . . 6
Step-By-StEp Procedure. . . . . ......... 8

Step-By-Step Assembly. . _ 8
Parts Mounting. . . . .
Wiring........... 10
Installing Fiberglas In Cabinet. . . . . . . 12
Installing Fiberglas in Midrange
SpeakerS...................... 14
Wiring And Mounting Midrange
SpeakerS................ ...... 14
Installation Of Speakers. . , , , , ...... 16
Wiring The Midrange Speakers To
The Crossover Network. . . . . . . . . . . . 16
Checking Cabinet For Air Leaks, . , . . , 18
Final Assembly. ...... . . . . . . . . . . 19

Installation....................... 20
InCaseOfDifficulty...... ....... 20

Service Information, , . , . . , _ , , 21

Service........... ..... 21
ReplacementS. . . . .. . . . . . 22
Shipping Instructions, . . . .. ........ 22
Warranty............. ..... 23

All prices are subject to change without notice.
The Heath Company reserves the right to discon-
tinue instruments and to change specifications at
any time without incurring any obligation to
incorporate new features in instruments pre-
viously sold,

Capyriam I963

Heath Company 2/1/63