RCA BN-6B User manual
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EQUIP
MENT
LOST
OR
DAMAGED
IN
TRAN
SIT
\Xlhen
delivering
1he
equipment
10
yo
u.
the
truck
driver
or
carrier's
agent
will
present
a
receipt
for
your
si
gnature
.
Do
not
s
ign
it
until
yo
u huve I
a)
in
s
pected
the
comainers
for
visible signs
of
damage
and
(h )
counted
the
containers
and
compared
wi
th
the
amount
s
hown
on
the
sh
ipping
papers.
If a
shortage
or
if
evidence
of
damage
is noted, insist
that
notation
10
chat effect
be
made
on
th
e s
hipping
papers
befor
e
yo
u sign
them.
Further,
after
receivini;
the
equipment,
unpack
it
am! in
spec
t
thoroughl
y
for
concealed danrnge.
If
concealed
damage
i,
ti scovered,
immediately
notify
rhe
carrier,
co
nfirming
chc
nmification
in
wr
i
ting.
and
sec
ure
an
inspection
report
.
This
item
should
be
unpacked
and
in
spec
ted
for
damage
W I
THIN
15
DAY
S afcer rece
ip
t.
Repo
rt
all
s
hortages
and
damage
s
10
RCA. Broudcast
and
Te
levision
Department.
Camden
2, N. J.
Radio
Corporation
of
America
will tile
all
claims
for
lo
ss
and
damage
on
thi
s
equipment
so
long
as
the
inspection report
is
obtained.
Dispo
sition of 1he
damaged
item
will
be
furni
s
hed
by
RCA.
REPLACEMENT PARTS
AND
ENGIN
EERING SERVI
CE
RCA field
eng
ineer
ing
service
is
avai
lable
at
current
races.
Reque
sts
fot
field
engineering
s
ervice
ma)'
be
addre
ssed
10
yo
ur
RCA
Broad
cast Field Represenliltive
or
the
RCA
Service
Company
, I
nc
..
Broadca
st
Service Divis
ion
,
Camden,
N.
J.
Tclc1,hone:
WOod
l
awn
3-8000.
\X/
h
en
order
i
ng
reph1ceme111
parts,
please
i;ive sy
mbol
,
description,
and
swc
k
number
of
each item o
rdered
.
The
par!
whic
h
will
be
supp
lied ai;ains1
an
order
for
a
replacement
item
ma>
•
not
be
an
extt
cr
dup
licate
of
the
original
part
.
However,
it
will
be a satisfactory
rep
l
acement
differ
ing
only
in
minor
mechanical
or
elenricnl
characteristics. Such
differences will
in
no
way
impair
t
he
ope
r
ation
of
the
equipment.
The
following
1abulu1ions I.isl service
p11rL~
and
electron
tube
ordering
ins1ruc1
ions
acco
rding
10
your
geographical
loca
1i
on.
SERVICE PARTS
LOC
ATIO
N OR
DER
SE
RV
ICE
PA
RTS FROM:
Continental
United
States,
including
Alaska
and
Hawaii
RCA
Electron
Tube
Divi
s
ion
,
Pare
s
and
Equ
i
pmenr.
P.
O.
8(lx 654, Cam-
den,
New
Jersey
or
through
your
nearest
RCA
Regional
Oflice, Erner•
gency
orders
may
be
te
l
ep
hon
ed,
t
elegraphed
or
1eleryped
t0
RCA
Emergency Service, Bl
dg.
60,
Camden,
N.J.
(
Telephone:
WO
3-8000
).
Dominion
of
Canada
RCA
Victor
Com
p
any
L
imited,
1001
Lenoir
Street,
M
onireal,
Quebec
or
1hrough
your
lo
c
al
Sales
Representative
or
his
office.
Outsi,de
of
Comi
n
enra
J
United
Scates, Alaska,
Hawaji
and
rhe
Dominion
of
Canada
RCA I
nternational
Div
i
sion,
Cl
ark,
N.
J., U.S.A.,
or
throu
,
i:;h
y
our
l
oc
al
Sales
Rep
resentative.
ELECTRON TUBES
LOCATION
ORDER
ELE
C
TRON
TUBES
FROM
:
Con1·nen1:il
United
Sta
tes,
including
Al
aska
Local
RCA
T u
be
Distribu
t
or.
and
H
awaii
Dominion
of
Canada
RCA
Victor
Compan)
' Li
mited,
1001
Lenoir
Street,
Montreal.
or
th
r
oug
h you.r local Sales
Representat
i
ve
or
his oflice.
Qucber
Oucside
of
Continental
Un
i
ted
States, Alaska, Local
RCA
Tube
Distributor
or
from:
Tube
Depanmenr
Hawaii
and
t
he
D
ominion
of
Canada
RCA
In
t
ernational
Division
.
,o
Rockefeller
Plaza
New
York
20.
New
York,
U.S.A.
RETURN
OF
EL
ECTRON
TUBES
H
for
any
rea
so
n,
it
is
desired
co
return
tubes,
please
return
them
through
)'
Out
local
RCA
tube
d:
stributor,
RCA
Victor
Co
..
Ltd.,
or
RCA
I
nternational
Div.,
depending
on
your
location.
PLEASE
DO
NOT
RETURN
TU
B
ES
D
IR
ECT
LY
TO
RCA WI
THOUT
AUT
H
OR
I
ZATION
AND
SH
I
PP
I
NG
I
NST
R
UCTIONS.
It
is
importont
tha
t
complete
information
regarding
each
tube
(
including
rypc, serial
number.
hour
s
or
se
rvice
and
rc:ison
for
i1
s
rcrurn
)
be
given.
\Vhcn
ruhes
nre
returned.
they
s
hould
be
shi1>ped
10
the
addre
ss specified
on
the
Return
.Au
t
horization
form. A
copy
nf
the
.Return
Authorization
and
also
a Service R
eport
for
each
cube
shou
ld
be
packed wi
th
the
tube
s.
A1la11/11
J.
Georgia
1121
Rhode
s-
H
averty
Bl
dg.
I34 Peac
htree
Si.
N.W
.
JAckson
4-7703
Dall,,
s
35,
Te.-ras
79
01
Empire
Fr
eewa)
'
FLee1wood 2-391 I
D-
BTE·J
LIST
OF
RCA
REGIONAL
OFFICES
Bo
s
/011
J
6,
Mass.
Chic11go
5-1,
111
.
Room
2.i0I,
J
ohn
H
ancock
200
Berkley
St.
H
Ubbard
2-1700
Bldg.
1186
Merchandise
Mart
Plaza
DEiaware
7-0700
Ho/l
yu
•
ood
28.
Ca
lif.
RCA Bldg., 1560
N.
Vine
St.
HOil
y
wood
9-21
54
IJ1
·1111ch-S
u11
Fruucisco 2, Calif.
420
Taylor
St.
ORdway
3-8027
Kama
s
City
6, J\li
.sso11ri
.
HO
Home
Savings
Bldg
.
HA
rrison
1-6
480
Se,,ttle.
11'1
ashi11gJ011
2250
First
Ave
.. S.
MAin 2-8350
Cle
1•ela,1d 15.
Obfo
1600 Keith Bl
dg
.
CH
erry
1-.~450
'
ew
}'
ork
20, '
e11
• \'
ork
-'6
W.
49
th
St.
JUd
son 6-3800
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2
Figure I - Type BH-
68
Transistor
Portable
Remote
Amplifier
TECHNICAL
DATA
Power Requi red
AC Power : 117 v,
50-
60
cyc
l
es
, 5
wa
tt
DC
Supply:
Batter
i
es
Ml-11778
(not
sup-
pl
ied
with
Ml-11221-8)
Fuse
1
/1
6
amp
3AG
Transistor
and Diode
Comp
lement
5 2N
175
3
2N
109
1
2N35
or
2
N2111
(RC
A) Inp
ut
stages
and
succeed-
ing
ga
in
stage
(RC
A) Gai n
stage
,
driver
and
PNP
part
of
the
complementary
symmetry
output
stage
{Sylvania)
NPN
part
of
the
com-
plementary
symmet
ry
output
s
ta
ge
2
1N91
Ge
rmanium
rectifiers
Frequency Response
±1-1/2
db
at
JO
to
15
,000
cps
Source Impedance
150
ohms
Load
Impedance
30
ohms
Input
150/30 oh
ms
Output
600/150
ohm+
18
dbm
Gain
88
db±
2 db 150-ohm
source
to
600-ohm
load
Harmonic
Distortion
Less
th
an
Less
than
Less
than
Less
than
Less
than
Less
than
N
oise
Level
-52
dbm
1. 51
at
30 t o
50
cps
a
at
50
to
10
,000
cps
3
.%
at
10
,000 to
lf
,000
(+ 18
db
out
put
cps
1.
251
at
JO
to
50
cps
a
at
50
to
10,000
cps
1.
251
at
10
,000
to
15
,000
(+ 8
db
outp
u"t)
cps
Sin9le
channel
,
gain
68 db,
master
gain
control
set
at
12
, mixer
gain
at
16
.
correspond
to
signa
l
-to-
noise
·
ratio
70
db
at
rated
power
output
of+
18
dbm
.
Dimensions and Weight
Height - 5-
5/8
inches
Width -
16
-1
/2
inches
Depth -
10-1/2
inches
wei9ht
-
25
po
unds (approximat
ely)
Finish
-two
tone
umber
gray
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---
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-,,
...
~
--
-·-
--
~--
---
=--
c:::
-------
---
----
~------
--
3
DESCR
IP
TIO
N
The
Type
BN-68
Amplifier,
MI
-
1122
1-
B,
is
a
four
channel
unit
designed
especially
for
broadcast
programs
remote
fr
om
the
studio.
This
unit
amplifies
low
level
signals
to
a
level
suitable
for
transmission
over a
tele-
phone
line
to
the
studio.
Other
features
in-
clude
complete
cuing
and
monitoring
facili-
ties,
etched
circuit
boards, use
of
tr
ansis-
tors
and
ge r
ma
nium
diodes
and
of
either
batte
r
ies
or
self
-
contained
ac
power supply.
Th
e
BN-
68
amplifie
r
is
supplied
in
a
rugged
carrying
case
.
The
specially
designed
lid
may
be removed
from
the
hinge
pins,
tu
rned
over
and r
eplaced
against
the
side
with
the
mou
n
ting
grommets. In
this
position
the
lid
forms a
rest
for
the
entire
assembly
at
an
angle
which makes
the
control
panel
easily
accessible
for
operation
.
The
AC
power cord
is
supplied
clamped
inside
the
lid
of
the
carrying
case
. A w
eather-proof
canvas
carrying
case
MI-11377
is
also
available
as
optional
or
accessory equipment.
Circuit
Th
e
BN-68
Amplifier
has
four
separate
in-
put
channels
which
can
be
operated
eithe
r
6
CD
3
0
z
0
"'
Cl) ,
z - 3
0
CL
Cl)
IA.I
- 6
er
balanced
or
unbalanced. Balanced
operation
is
accomplished
by
plug-in
t
ransfor
mers
MI
-
11776
(992074-1) which
may
be o
rder
ed
sepa
rately.
The
2Nl75
low-noise
transisto
rs are used
in
the
input
stages
and
in
the
follo
w
ing
pr
e-
amplifier
stage.
nie
drive
r
stage
is
a con-
ventional
amplifier
stage
.
No
phase
inversion
is
necessary
since
a
comp
lementary symmetry
stage
is
used
in
the
output
.
An
isolation
pad
is
connected
to
the
transfo
rmer
prima
ry
to
protect
the
output
transistors
from
damage
in
case
of
shorting
the
line
.
The
VU
meter
both
monitor
s,
the
output
level
and
tests
the
battery
curre
nt.
A
sep
ar-
ate
flashlight
type
battery
is
n
ecessa
ry
for
vu
meter
illumination
wh
en
th
e
unit
is
opera-
ted
from
battery
supply
.
Batteri
es
are
not
supp
l
ied
w
ith
the
equipment
.
Lightweight
,
long
life
mercury
batteries
should
be
ordered
for
the
batte
ry
power
supply,
Th
e
battery
kit
MI-11778
may
be
ordered
which
includes
5
PR.
Mallory
lfl'Rl35R, 6. 5
volt
type
and one
RCA
IIVS036,
1.5
volt
type.
Th
e ac p
owe
r
supply
consists
of
a f
ull
wave
re
ctifie
r
circuit
u
sing
germanium
diodes
and an
r-
c
filter.
"""
30
~o
1
00
200
300
~00
1000
300
200
0
FREQUENCY IN C
YCLES
PER
SECOND
0
~000
10000 I
~0
00
.4
·
8946054
-0
Figure 2 - Typical Frequency Response Curve
\
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4
T
RANSISTOR
M
IX
ERS
PRE
AM
PS
r - - - -
I
MIC 1
~lllo----0---0'
~S2
A
TI
MI
C2
~11
AT
2
M
IC3~
11
An
M
IC
4
o--1
ATd
------,
I
TRA
NS
ISTOR
AMPLIFIER ISOLATION
PAO
C
UE
MIC
I
SWHCH
l l
N(
MONITOR
OUTPUT
TRANSFORMER
vu
PAO
Figure 3 - Block Diagram
IN
S
TALLATION
Transistors
All
transistors
are
shipped
in
place.
The
sockets
are
mounted on
the
printed
circuit
boards.
Replacement
transistors
are
easily
plugged
in
as needed.
CA[f['JON:
Do
not
remove
or
inser
t the
transistors
when
the
po
w
er
is
ON.
Transi
s
tors
nuy be
dam
ged
resul
t
in
g
in
excessive
noise
an
d d
istor
t
ion
.
Allow
approxi
m
ately
1
minute
after
power
is
o
ff
b
efore
removing
tran-
sistors.
Internal
Connections
The
BN-6B
amplifier
is
shipped
connected
for
either
150
or
30
ohm
unbalanced
input
and
a
600
ohm
output.
A plug
is
provided
for
each
input
socket.
For an unbalanced
line
either
30
or
150
ohm
microphone
may
be used.
FOr
a
balanced
line
the
plug-in
transformer
MI-
11776
may
be
ordered
.
The
sockets
are
con-
nected
for
150-ohm
input balanced
line;
how-
eve
r,
for
a 30-ohm
balanced
line,
move
connections on the
socket
from
terminal
1
to
terminal 2
and
from
terminal
5
to
terminal
4,
Installation
of
Batteries
The
preamplifier
is
shipped
wi
thout
batteries.
These
may
be
ordered
separately
as
Ml-11778 which
includes
five
PR.
Mallory
11TR
1
35R
-
6.5
volts
and
one
RCA
#\1S036
-
1.5
volts.
To
install
the
RCA
battery,
remove
the
cover
and
place
it
firmly
in
the
clips
se-
cured
to
the
top
shelf
of
the
chassis
in
the
right
hand
corner.
A
cylindrical
case
holds
the
five
batteries
and
is
secured
by two
clips
fastened
to
the
bottom
of
the
chassis.
VU
t-eter
The
VU
meter mounted on
the
front
panel
is
a
standard
meter
and
provides
a means
of
measuring both
the
volume
level
of
the ampli-
fier
output
and the
battery
current.
To
mea-
sure
the
battery
current,
turn
the
POWER
switch
to
the
BATT
TEST
position.
Wh
en
the
meter
indicates
the
center
position
or
100,
www.SteamPoweredRadio.Com
the
battery
current
is
at
its
peak, 32
volts.
The
amplifier
should not be
operated
with
the
battery
reading
below 1
0%
less
than
the
100
reading.
The
VU
meter
attenuator
is
designed
to
give a meter
reading
of
O on the
VU
scale
with
an
output
of
8
dbm.
The mercury
type
batteries
are
capable
of
appr
oximately
40
hours
continuous
operation
.
The
RCA
battery
which
supplies
the
meter
illumination
should
be changed whenever
the
light
appears
dim.
AC
P
owe
r
Co
rd
The
eight
-
foot
power
cord
is
supplied
folded and
clipped
into
the
lid
of
the
carry
-
ing
case
as
sho
wn
in
f i
gure
7. The
AC
con-
nector
on
the
back
panel
is
a t w
ist
lock
type.
Co
n
nect
the 'power cord matching
plug
to
the
amplifier
connecto
r and
plug
the
other
end
into
a convenient
117
-
volt
ouUet.
5
C
UE-MIC-
I Switch
Plug
a
set
of
headphones
in
the
PHONO
jack
provided
for
monitoring the
output,
Nor-
mally
the
signal
from
the
studio
is
strong
enough
to
hear
the
signal
on
line
gain;
if
the
signal
should
be weak,
turn
the
spring
return
switch
to
the
CUE
position.
'fhe
signal
will
then
be
amplified
through
the
BN-68
amplifier
to
the
headphones
independent
of
whether
the
line
is
balanced
or
un
balanced.
This
is
a
spring
return
switch
to
assure
operation
on
MIC-1
position
at
all
times.
Bind
i
ng
P
os
ts
Three
binding
posts
are
mounted
on
the
back
of
the
chassis,
two
for
the
line
output
connection
and one
for
ground.
The
output
connection
is
made
through
the
telephone
line
for
renote
operatio
n.
OPERATION
When
the
source
of
power
to
be used
has
been determined,
AC
or
battery,
set
the
amp-
lifier
on
a convenient
surface
and
adjust
the
handle
underneath
as
desired.
Then
proceed
as
follows:
1.
If
AC
power is
to
be used,
plug
the
cable
connector
into
the
receptacle
on
the
back
of
the
amplifier
and
connect
to
a con-
venient
117-volt
ac
outlet
. Turn
the
POWER
switch
to
the
AC
ON
position.
2.
If
batteries
are
to
be used,
turn
the
POWER
switch
to
the
BATT.
TEST
position
and
check
the
VU
meter
reading.
If
the
reading
is
satisfactory,
not
below
10%
less
than the
1
00
reading,
turn
the
POWER
switch
to
BATI
ON
position.
3. Plug headphones
in
the
PHONO
jack
pro-
vided
for
monitoring.
4.
Plug
in
the
microphones;
all
four
re-
ceptacles
may
be
used
at
one time
if
desired.
Low
impedance
broadcast
microphones such
as
the
RCA
BK-SA
or
BK-6
A
are
recommended.
Make
certain
that
each
cab
l e
on
the
microphones
selected
has a
connector,
plug
XLR-3-1
2C,
MI
-
11089A,
matching
the
receptacles
on
the
BN-6B
amplifier
.
MAINTENANCE
Fuse
Re
pla
ceme
nt
When
replac
ing a
fuse
,
make
sure
that
the
replacement
fuse
is
of
the
same
type
and
r
ating
, 1/ 16
amp
3AG
,
slo
-
blo,
as
the
one
furnished
with
the
amplifier.
To
use
a
fuse
of
higher
rating
for
replacement
purposes
will
needlessly
endanger
the
windings
of
the
power
transformer.
Se
rvici
ng
of t
he
Et
che
d Wiri
ng
Boa
rd
A
ssem
blies
The
etched
wiring
boards
are
made
of
.
062
inch
thick
paper
base
phenolic
laminate
to
one
side
of
which
is
bonded a
thin
sheet
of
copper.
The
conductor
pattern
is
formed
by
an
etching
process.
Component
leads
are
threaded
through
holes
which
are
punched
into
the
board.
The
ends
of
the
leads
extending through
the
board
are
bent
over
against
the
copper
conductors
.
The
comp
l
ete
assembly
is
subse-
quently
dip-soldered
.
Components
may
be r
eplaced
easily
by
follo
w
ing
these
simple
inst
r
uctions.
Care
should
be
observed not
to
break
or
crack
the
board
oy
undue
stress
or
to
damage t be
bo
n
d-
ing
adhesive
by
applying too
much
heat
during
solde
ring.
I. T
oo
ls Required
a.
A
small
(35
watt
or
less)
pencil
type
soldering
iron
.
'
J
www.SteamPoweredRadio.Com
b. A
pair
of
small diagonal
cutters
.
c.
A
pair
of
small long nose
pliers.
d. A
sc
r
ibe
or
pick.
e.
A
sma
l l
knife
.
2. E
me
rg
e
ncy
Repairs
If
it
is
kno
wn whi
ch
component is
defec
-
tive
,
it
may
be
replaced w
it
h
out
remov
i
ng
the
board
fr
om
i
ts
mounting.
a, In t he
case
of
a sm
all
compone
n
t,
such
as a 1/ 2 or 1 w
att
r
esisto
r , cut the
compon
-
ent
in
half us
in
g d
iag
on
al
pl
i
ers
. Crush t he
body
by
means
of
t he
lo
ng nose
pl
i
ers.
T
his
is
done
to
obtai
n ex
tr
a
lead
le
n
gth.
In
the
case
of
large
r
compo
nen
ts
,
cl
ip t
he
le
ad
s
as
close
as
possib
le
to
the
colJ1P()
n
ent
body
.
TO
REM
CVE D
EFE
CT
IV
E CO
MD
O
NENT
CO
MP
O
NENT
CUT
Off
HE
RE
T'.:)
INS
TALL
NEW COMP
ONENT
BOARD
BENO WIRE
WIT
H
PLIERS
TO REMOVE COMPONE
NT
FROM T
OP
OF C
IR
CUIT BO
AR
O
SO
LD
ER PI
GTA
I L
OF
NEW COMPON
EN
T
TO
LOO
P
ED
ENO,
Figure 6 -
Me
t
hod
fo
r
Re
placement
of
Componen
ts on Print
ed
Circui ts
7
b.
Using
lo
ng nose
pli
ers,
fo
rm a
loo
p
of
the
lead
ends as
shown
in
fi
gure 6,
c.
Th
read
the
leads
of
the
ne
w
component&
t
hr
ou
gh
these
loops. Cut
off
the excess
lead,
crimp
and
solder
the connectio
n.
3. Pe
rman
e
nt
R
ep
ai
rs
a.
Remove
the
hardware
fastening
the
board
to
the
chassis
and
tilt
the
board
up
.
b.
Isol
a
te
the
defective
compo
n
ent.
If
it
is
necessa
ry
to
discon
n
ect
a component f
rom
the
circuit
for
test,
heat
the
Ju
n
ctio
n
of
t he
compone
nt
lead
and
the etch
ed
w
iri
ng w
ith
the
solde
r i ng i ron.
The
heat
should
be
con-
cen
trated
on
the
com
ponent
lead
r
ather
than
the
etc
h
ed
w
iri
ng
pattern
.
Pry
up a nd
st
r
aighten
the be1,t over
portion
of
the
com-
po
n
ent
lead
with
a
knife
blade,
then
pull
lead
throu
gh the hole
with
Plie
rs.
c.
To
remove
the
defective
component,
sn
ip
the
l
eads
off
at
the
component
side
of
the
board,
see
fig
u
re
6,
d. Using a
small
solde
ring
iron
(35 w
atts
or
less)
heat
the
leads
and r
emove
them
fr
om
the
pri
n
ted
w
iring
side
of
the
board
.
Be
care
f
ul
not
to
apply
too
much
heat
or
fo
r
ce
to
avoid
damage
to
the
thi
n copper
co
nductors.
e.
Clean
and
preform
the
leads
of
the
new
component and in
sert
th
rou
gh
the
holes
until
the
component
body
is
tight
agai
nst
the board.
f.
On
the
circuit
si
de,
grasp
the
compon-
ent lead
and
bend
it
over
in
the
di
r
ect
i
on
of
the c
ir
cu
it
pattern.
g.
Crimp
the
w
ire
tightly
agai
ns t
the
board
(see
figure
6),
and
cut
off
the
excess
co111>one
nt
lead. Leave about 1/ 16 inch
of
w
ire
protruding
fr
om
the
e
dge
of
th
e hole.
h.
Heat
the
lead
and
apply
rosin
core
solde
r .
DO
N(JI'
USE
PASTE
OR
ACID
FLUX.
Remove
ex
cess
r
osi
n
from
the jo
in
ts
w
ith
alcoh
ol
.
i . R
ep
la
ce
t he
ci
r
cuit
bo
ard,
us
in
g the
or
ig
ina
l hardware.
~.
Repl
a
cement
of
Tr
ans
ist
or
Soc
ke
ts
Foll
ow
the
sam
e
pr
oced
ur
es
outlined
fo
r
components.
The
ti
ny t r
ansis
t
or
sockets
ar
e
mo
un
ted on
to
p
of
the c
ir
cuit
bo
ar
d.
www.SteamPoweredRadio.Com
8
Voltage Readings
The
following
table
shows
the
typical
voltage
to
ground
readings
at
the
transistor
socket
terminal.
These
readings
were
obtained
with
an
RCA
Voltohm
ist
.
The
valu
es
are
approximate and
may
vary
t:20
%due
to
production
tolerances
on
transistors.
The
measurements were
made
with
all
g
ain
contro
ls
at
zero,
plugs
P5, P6, P7 and
PS
in
the
unit
and
th
e
lin
e
voltage
was
11
5v
a.c.
VOLTAGE
CHART
Transistors
Pin
4
Capacitors
(-)
Terminal
XQl
-4.2V
cs
-15.lV
XQ2
-4.2V
C12
-34.
3V
XQ3
-4.2V Cl3 -38.
7V
XQ4
-4.2V
C14
-42,9V
XQ5
-11.
lV
C15
-2
6.9
V
XQ6
-9.0V
C16
-15
.9
V
XQ7
-15.0V Cl8 -34,
3V
XQB
-34,3V
XQ9
0 V
LIST
OF
PARTS
Sy
,n
bol
No. Stoel& No. D,
awi,.g
No.
Desc
ription
ATl
to
AT4
213300
758505
- 2
Resistor:
variable,
c
omp.,
2
s.
000
ohm
t10%, 2
.,,
AT
S
213299
7
58
50
5-1
Resistor:
variable
, comp. , 1
0,000
ohm
tl0
%,
2 w
CAPAC
I!
ORS
:
Cl 106114
990130
- 1
ele
ct
rolyti
c , 10
µ.I,
10 V
C2
213301
98
4655-
26
e
le
c
trolytic,
l.0
µI,
50
V
CJ
79181
984655
-1
6
electrolytic,
2.0
µ.I,
50
V
C4
213301
984655
-2
6 e
le
ctrolytic
,
1.0
µ.
f,
50
V
cs
213302
984655
-2
7
electro
l
yt
i
c,
so
µ.I'
50 V
C6
10611
4
990130-1
el
ec
trolyti
c,
10
µ.f,
10 V
C7
213301
984655-26
electrolytic,
1.
0
µ.f,
50
v
C8
106
114
990130
-1
elect
r o
ly
tic,
10
µ.
f , 10 V
C9
21330
l 984655
-2
6
elect
ro
lyti
c,
1.0
µ.f,
50
v
Cl0 106
114
990130
- 1
electrolyti
c , 10
µ.
f,
10 V
Cll
213301
984
655
-2
6
electro
lyt
ic,
1.0
µ.f,
50
V
Cl2
21
3304
984655-29
electrolytic,
2
50
µ.
f ,
50
v
Cl3
to
Cl6
21
3303
98
4655
-28
electro
l
yti
c ,
100
µ.f,
50
v
Cl
7
210001
984655-30
electrol
ytic
, 250
µ.f,
6 V
C
l8
213304
984655-29
electrolyti
c,
250
µ.
f,
so
y
Cl9
10
6055
990130-10
electro
l
ytic,
100 µ.f, - 10
+2
50%,
15 V
C20
7918
1
984655
-1
6
electrolytic,
2. 0 µ.f,
50
V
CR1,CR2
210963
Rectifier:
germanium ( IN91)
El
to
E3
46907
181193-5
Post:
bi
n
ding
Fl
211428
990157
-
102
Fuse:
1/
16
amp. , 3 AG
Jl
to
J4
213288
892
69
59
-1
Co
nn
ector:
fe
m
ale
, 3
co
n
t.
J S
to
J8
105783
88288
6- 2 Co
nne
c
tor
:
female,
8
cont.
www.SteamPoweredRadio.Com
9
Sy,,.bol
No
.
Stoel&
No. Drawi,eg No.
Descr
iption
J9
98593
18
0882-
1
Jack:
female,
si
n
gle
con
t.
J
10
5
44
72
889482-3
Connector:
AC
Ml
213286
486
6
39
-1
Meter:
vu
Pl
to
P4
Not
used
PS
to
PB
21
3298
8926985-501
Co
nn
ec
tor
:
male,
9
co
nt
.
RISISfORS:
fixed,
c
oaPosition
unl
ess
otherwi
se sPe
ci
f i ed
Rl
735730-89
180,000
ohm
tl0
%, ½ w
R2
735730
-77
18,000
ohm
tl0%,
½ w
R3
735730
-
129
100
ohm
~%,
½ w
R4
735730-
1
32
75
ohm
t5%, ½ w
RS
735730-74
10
,000
ohm
tl0%,
½ w
R6
735730-210
130,000
ohm
t5%, ½ w
R7
735730-50
100
ohm
tl0%,
½ w
RB
735730-
72
6800
ohm
tl0%
, ½ w
R9
735730-68
3300
ohm
tl0%,
½ w
RlO
735730-2
12
160,000
ohm
t5%,
½.,
Rll
735730-
1
33
82
ohm
t5%, ½ w
Rl2
735730-70
4700
ohm
tlO
'J.
, ½ w
Rl3
735730-73
8200
ohm
tl0%,
½ w
Rl4
73
5730-68
3300
ohm
tl0%,
½ w
Rl
5
735730
-13
0 62
ohm
t5%, ½ w
Rl6
735730-87
120,000
ohm
tl0%,
½ w
Rl
7 73
57
30-
130
62
ohm
t5
%, ½ w
Rl8
735730-70
4700
ohm
t10
%,
½ w
Rl9,R20
735730-125
39
ohm
t5%, ½ w
R21
735730-139
1
50
ohm
t5%. ½ w
R22
735730-70 4
700
ohm
tl0
%, ½ w
R23
735730-89
18
0,000
ohm
tl0
%, ½ w
R24
735730
-77
18,000
ohm
tl0
%, ½ w
R25 7357
30-129
1
00
ohm
t5%, ½ w
R26
735730-
1
32
75
ohm
t5%, ½ w
R27
735730-74
10,000
oh
m
t10
%, ½ w
R2
8
735730-89
1
80,000
ohm
tl0%,
½ w
R29
735730-77
1
8,000
ohm
tl0
%, ½ w
R30
735730-129
100
ohm
t5%, ½ w
R31
735730-
132
75
ohm
t5%, ½ w
R32
735730-7
4
10,000
ohm
tl0%,
½ w
R33
735730-89
180,000
ohm
t10%, ½ w
R
34
735730-77
18,
000
ohm
tl0%,
½ w
R35
735730-129
100 ohm t
5%,
½ w
R36
735730-132
75
ohm
t5%, ½ w
R37
735730-74
10,000
ohm
tl0%,
½ w
R38
735730-
65
1800
ohm
t10
%,
½
VI
R39 73573
0-175
4300
ohm
t5%, ½ w
R40 7
35732
-1
64
1600
ohm
t5%, 2 w
R41,
R42
73
5731-
1
37
120
ohm
t5%, 1 w
R43
735730-
146
300
ohm t5%, ½ w
R44
735730-203
6
8,000
ohm
t5%, ½ w
R45
735730
-1 54 620
ohm
t5
%, ½ w
R46
735730-180
7500
ohm t5%, ½ w
R47
735730-70
4700
ohm
t10%, ½ w
R48
735730-61
820 o
hm
tl0%,
½ w
R49
735730
-1
54 620
ohm
t5
%, ½ w
R
50
73
5730-158
910
ohm
t5%, ½ w
R
51
7
35730
-1
20 24
ohm
t5%, ½ w
R52
214949
72238
4
-230
wire
wound,
1.
5
ohm
t5%, 1 w
R53
735730-72
6800
ohm
HO%, ½ w
R54
735730-74
10,000
ohm
t10%, ½ w
Sl
213296
486640-1
Switch:
rotary,
waf
er
type,
3
sec.,
4
pos.
S2 21
3297
4
8664
1·
l
Switc
h :
rotary,
wafer
typ
e,
l
sec.,
2
pos.
--:
l
Tl
213305
9920
43·1
Trana
former:
o
utpu
t
T2
213
30
6
99
2086·1
Transformer:
po
wer
T3
213627
9
92074-1
Tra
nsfo
rm
er
:
input
XFl
20
5914
8811104-1
Holder:
fuse
www.SteamPoweredRadio.Com
10
Symbol No. Stoclc No.
XQl
to
XQ9
215818
32098
32661
213290
21
3291
203645
3092
5
214647
17268
3007
5
213293
213292
213
29 5
213289
Drawing No.
8888533-7
8926984-501
180707-3
878243-1
8926966-1
4776
4-1
181
65
4-1
87 5443-9
8941269
- 1
737820-505
712336-507
8926999
-501
8926994
-501
8926972
-501
8924067
- 1
Socket:
transistor
NISCKLLANEOUS:
Desc
ription
Cable:
power,
with
male
and
female
connectors
Cable:
powe
r,
wit
h 2
co
ntact
male
co
nn
ectors
Co
nn
ecto
r :
female,
2
con
ta
ct
Cap:
battery
tube
Escutcheon:
panel
ov
erlay
Foot:
rubber
Han
dle:
carrying
case
Holder:
battery
Knob:
micropho
ne
controls
Knob:
"o
ff-on"
and
mic
sw
it
ch
Prin
ted
Circu
it:
amplifier
com
p
one
nt
a
ssembly
Printed
Circu
it:
power
sup
ply
filter
Spring:
battery
co
nta
ct
press
ure
Tubi
ng
:
battery
holder
Figure 7 -
BH
-
6B
Remote
Amplifier (Lid
and
Cable
in
Carrying Position)
www.SteamPoweredRadio.Com
2Nl75
f\1
QI
~
Q3
p 4
,J'
/,y
·o
.,
>"
,,.-c
~
k
,...
> ~J
1'
2Nl75
Q5
C3
R38
1800
C1S
+ 100 +
e--
2
k\OC,
2.N1()'l
Q7
RIO
Q6
C
4-
+
/\.,
-
-------1
R3~
4-300
-!5%
CH,
100
•
e·
CIS
R12
+100
1.0
f\13
8200
PC
2.
POWER
SUPPLY
FILTE.
R
lh---~~-~
120
120
IW
,,-
.
...
,,.
IW
Cl2.
R40
Cl~
1600
-;
250
+
100
2w-sr.
2.N109
QB
Cl4-
+ 100
·---------
--
--
-
INPUT
TRANS.
.-
- - - - - - - - - - - - - - -
--i
L.
- -
T3
1
UNLES':i INDICATED ornE.RW\'5E
/\LL
RE.S.ISTOR
VI\Wf.5
/\RE.
1N
OHM':,
-
½.VIATT-10¼
AND
ALL
CAPl\tlTOP.$
IN
MICRO-
FARADS.
®""
INOICATE.5 TE.RI'\.
FOR
CONI\E.CT\ON
TO COMf'(INE.NT::,
n.TE.RHI\L
TO
PRIIITE.O
CIRCUIT
~6ARO.
cs
!iO
+
R21
150
5~
T1
S2
SHO'NH
IN
POSITION
1,
P051TIOH1
·
MIC
I
POSITION
2·
CUE.
(SPRING
RHURN)
13-14
r
GIID
E2
._----1-----1---------..::E..::~-<"l
OU
TP
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CBS
RADIO
S
HEE
T
No.
7
AUDIO
FACILITIES
MEASUREMENTS
STATION
. .
;3/
JI
-{.8
Studio.
..
.................. .
MEASURING
DATA:
Mic.
channels measured
as
per
Dwg.
TD-80
Circuit
#I,
unless
otherwise noted.
l
ine
channels measured
as
per
Dwg
.
TD-73A,
Circuit
#I,
unless
otherwise noted.
Power
levels
expressed
in
DBM
(0
DBM
= I
milliwatt.)
Oscillator for measurements..................
..
..............
..
#
.......
...................
..
........
..
..
...
..
D
ist
ort
ion
meter for meas.
....
..
.
..
. ......................#
...
..
. .
Tra
ns
mission
set for meas.....................
..
................
...
.#
......
....
.
CONDITIONS
FOR
MEASUREMENTS
Input
to
1
1_/?
1 r-·-
>:
II
:3
~
I
Output
from
:I
fl
C
Gain
S
etting
(08
from
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xi
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(71)
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DB
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DIS
T
ORTION
MEASUREMEN
TS
IN
%
RMS
CP
S
CPS
Unweighted • 7 I
\I
-
.r
z I-
G-
7
II
RESPONSE-FREQ.
MEASUREMENTS
IN
DB
DEV
I
ATION
FROM
1000
CPS
LEVEL
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so
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ME
ASURED
BY.............. ............................................
..
....
.
Fo
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T.0,•7•C8S
9'18
•4/
SS
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