Heathkit AA 151 Notice Montage Kit 1 a 17

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RESISTOR AND CAPACITOR COLOR CODES

RESISTORS

The colored bands around the body 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 15% or 110% respectively. The absence
of a fourth band indicates a tolerance of 120%.

CODE
Isr DIGIT 2m DIGIT MULTIPLIER

COLOR

BLACK
BROWN
RED
ORANGE
YELLOW
GREEN
BLUE
VIOLET
GRAY
WHITE
GOLD
SILVER

I0

I00

I.000

IQOOO
I00.000
L000.000

l0.00 0.000

. I00.000.000
L000.000.000

I I OONOMDUN-O

GOLD 157.
SILVER tIO '7.
NO BAND t20_Zo

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, 1 watt and 3
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
Yes-#33:. ___~ 4 v . .0 o o
I (0347Kn)
I-ORANGE-LOOO-
WI}- SILVER == TOLERANCE

1'. I070
RED -2

RED-2_____ 22x 100.009
GREEN-IO0.000 (on 2.2 MEG.)

{-\NO BAND uTOLERANCE

1:20 7:.

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 ZNODLGIT MULTIPLIER TOLERFZ: 2 7 X IO'O
\

\
3:33: RED VIOL RED

RED
ORANGE
YELLOW
GREEN
BLUE
VIOLET
GRAY
WHITE
GOLD
SILVER

It.
I o

H- I H-

EIIIIIquN

I IoownuéuN-o
IIOONGUDWN-O

CHARACTERISTIC

5: 27001111? 1 5 %

OR .0027 UN

WHT. OR
BLK. DOT
INDICATES
MICA

CHARACTERISTIC"
SEE NOTE I BELOW

(VALUE m uuf-su: nor: 3 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
Co OR IS? DIGIT 2N DIGIT MULTIPLIER TOLER. 7o
BLACK 0 0 - I 120
BROWN I I -- IO tOJ
RED 2 2 - I00 - 12
ORANGE 3 3 ~ -- I.000 - 12.5
YELLOW-* - 4 4 IOoOOO -- - .\
GREEN ~ 5 5 -- 10.5 435 .g .1
BLUE 6 6 --- -- - - "~ ,
VIOLET 7 7 ----- - - - -- '
GRAY 8 8 - - $0.25 - ' -
WHITE 9 » 9 - 21.0 1IC/
/ ORG ORG BLK GIN
| I a .
TEMPERATURE 3 3 x I #51
COEFFICIENT-
TEMPERATURE SEE NOTE 2

coerncwm- BELOW 33 uuf 25%

(VALUE IN nut-sac NOTE 3 BELOW)

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, 118-153 (a 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 centigrade. Refer
to EIA Standard, Its-198 (a Standard of Electronic Industries
Association.)

3. The farad is the basic unit of capacitance, however cap-
acitor values are generally expressed in terms of ufd (micro-
farad, .000001 farad) and uuf (micro-micro-farad, .000001
ufd); therefore, 1,000 uuf = .001 ufd, 1,000,000 uuf = lufd.

USING A PLASTIC NUT STARTER

A plastic nut starter offers a convenient method
of starting the most used sizes: 3/16" and 1/4"

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,

6-32
(3448 and 6-32). When the correct end is pushed ©