Heathkit IB 1 Manual

Page 1

ASSEMBLING AND
USING YOUR

l/gai'hkif;

Impedance Bridge
Model "34

THE HEATH COMPANY
BENTON HARBOR. MICH

PRICE $1.00

4 V

Page 2

tifitiit21223::1311111. USEFUL INFORMATION FOR Kll BUILDERS :1
Resistors are identified by a color code used in scvcral bands around ll): resistors. There are two

general types oi resistors. One. the uninsulated lypc, has the connecting wircs bound around the ends. I ,
The other. the insulated type. has the wire connected internally and coming out lhe ends. Th: rcsisl- EBB: A
ance code uses thrcc bands or colors, while a iourlh. usually silver or gold. indicates the tolerance. The

colors are arranged so that the first two indicate the first two figures of the resistance, while NW 1/}
rhr third indicates the number of digits (zeros or multiplier) which follow the first two figures 7'
On nninsulated resigturs. the body is the first figure, the end color the second figure, and the
dot the numbcr of digits. 0n insulatcrl resistors. \lle band nearest the end is the first figure,
the next band is the second figure and the third band the number oi digits.

The chart shows approximate sizes which vary with manufacturers. To determine wat-
tage size necessary multiply current through resistor in amperes by voltage drop across
resistors in volts, Example-A plate loading resistor for a tube drawing 10 milli-
amperes (.01 Ampercs) has a voltage on one side of 300 volts and on this other side
200 volts, giving a drop of mo volts Tbcreforc [on volts x .OIA. : 1 Watt. WATTAG E SlZES

A highcl wattage rcsxstor can always be substituted for smaller sum.

WATTAGE. Resistors: are rated as to wattage (power dissipation) according to size. !

Uninsulatcd Body Color End Color Dot Color (/NNSULfiTEo Exa m [es INfULA FED TYPE
Insulated First Rim: Second Ring Third Ring TYPE p gaff/i 56.7an
runn- Hm I-nrnn- set-um: Figure .\'nmlu~r or mg". " 7.0/5" 53th
Ii

\\

BROWN RE D ORANGE BROWN RED ORANGE
1 L 000 l. 7. 000

a

'Aoa-.1.-.'.'lmuwt-ID

:; Yn-th'a-z:

.
While

Some Popular Sizes of Resistors

|II-2§IS|'|\'(I>. IX (His unln 0" "NT I|\'D l-lxl) (Ill sl-itnxl) Inxn 001' UN 'lllllln Int)

25m
11ml)
llllJJlln
221: am;
. "Bu-hm

(w) H:- mm ra-
.4 30'}? Illll!"llx('l'.

'llu- [ollrllx ring m u-.- .-m: may in- xilvrr (in-2 mi.
(Ir-runu-t) or :1 may hr mum-d mun-Ir \tlllrrll man

Condenser Code

Condensers use the same code as resistors and arc read in micromierolarads.

If there is one row of dots, they arc read in direction of arrow or if manufacturer's name appears in the same direction as
name. If two rows oi dots appear, ir can either be oi two dlilerpm codes: Tin: RMA or the AWS (American War Standard).
In the RMA. the top row a! dots are lhc first three figures (carried to three figurcs). the bottom row are left to right the voltage
rating, tolerance. and decimal multiplier.

In the AWS code. the top row of dots are the firs: three figures while the bottom row are. left to right, characteristic.
tolerance, and decimal multiplier.

Examples
R M A

ml :\~\§\ \~\\\\\\

.4
RED

W BI ' i L
GREEN BROWN BROWN RED GREEN BROWN 714007 GREEN uLACK BROWN
2 s o 1 z 5 o ALWAVS 5 o o
250 MMF = .000 25 MF IZSO MMF =.ODIZ SMF BLACK 500 MMF = .0005

Some Commonly Used Sizes of Condensers

MMF. MF. FIRST DOT SECOND DOT THIRD DOT

10 .00001 Brown Black Black
5;] .DUOUS Green Black Black

100 .0001 Brown Black Brown

250 .00025 Red G rcen B rown

500 .0005 01 can B lack Brown

1000 .001 _ Brown Black Red

3000 .003 Orange Black Red

10,000 .01 Brown Black Orange

.n- M...- W