Sparta CENTURY Series User manual

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CENTURY
ERIES
Models
4710,
4715,
4720
and
4725
Record Module (Part
of
Models
4610, 4615,
4620
and
4625
R/P Systems)
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Division
of
Cetec
Corporation
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5851
Florin-Perkins Road, Sacramento,
Ca
. 95828 •
(916)
383-5353 • Telex 377-488 • Cable
SPARTA
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11
TECH ICAL
MA
UAL
CENTURY
SERIES
Models 4710, 4715, 4720 and 4725
R
cord Module (Part
of
Model
4610, 4615, 4620
and
4625 R/P
Sy
tern )
PRO
PR
I T
ARY
OTICE
part
El
ctroni
Corporation
propri
t
ry
data i
contain
d h r
1n.
ith
r
thi
docum
nt
nor
th
inform
tion
ontain
d h r
1n
ha I b
di
clos d
t
th
r
for
manuf
acturi
or
any
th r
purpo
xcept
authoriz
d in
writin
by
Sparta
El
ctronic
Corpor
ti
n.
iO
l 973
098-4710 5.00
,
$[}>~1~11~
E
ECTRO
IC
CORPO
ATIO
1
FLCRI
•P
RKIN
RD
D
CR
M
NTO,
CAUFDR
IA

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CONTENTS_
CENTURY SERIES FEATURES
INTRODUCTION ......• •. •..•••.•..••.• • • . .•. , • , , .
GENERAL
DESCRIPTION , •.• .•• ..•.. •• .• . .....•••. .• •
SPEClFICATIONS
.. .................. .. ......... .. .
INSTALLJ\TION
UNPACYJNG ............. . ............ . . . .... . . . . . . .
ENCLOSURES •..• •.•. . •.•••••.•••• . • • .•........•• • •.
AUDIO & CONTROL CONNECTIONS
" . .. ... .......... ..
RECORD PLUG : ................. .... ............
.. .
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3
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OPERATION
R ECORD PRESET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
E. 0. M. REC ORD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
RECORD LEVEL . • . . • . . • . . . . . . • . . • • . . • • • • • • . • • . . • . . • • 8
SOURCE SELECT
. .. .... .. .............., .... ....... . 8
TEST fUNCT I ONS
................. . . . . ............. 9
RECORDING PROCEDURE
.......... .............. ....
10
ELECTRONIC ADJUSTMENTS
GENERAL ..... . . ................ .. ... ............. 13
PROGRAM BIAS .... ...........
.. .............. ..
13
PRO GRAM BIAS TRAP . • . . . • • • • • • . • . . . . . • • • . • . • • • • • • • • • 14
REC ORD BIAS TEST CALIBRATION . .......
.. .............
15
PROGRAM RECORD EQUALIZATION. ......... • • • • • • • • • • • • 15
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ELECTRONIC ADJ USTMENT S ( Cont 'd)
PROGRAM
VU METER CALIBRATION
STOP TONE LEVEL .••••..• ••• .••. .• •.•••.. . ..•••. .
CUE TONE BIAS
CUE BIAS TRAP
....................... .. .........
..................................
E , O . M . TONE LEVEL • •...... • ••• •.•••. · •.. . . •. .•.•
TONE TEST C ALI BRAT ION • . ..•••.•..... . ........•..
ENC ODER LEVEL . • •.••••••. . •. •. ...• . •.•••• • ..• . • •
ELECTRONIC ADJUSTMENTS
AND TEST POINTS (P -4 2} ..
CIRCUIT DESCRIPTIONS
POWER SUPPLY ... ..... ....... .... . ... ... .... ... . .
CONT ROL CIRCUIT
RECORD CIRCUITS
1 50 Hz GENERATOR . .. ..• . ••....• • .•.....•...... . .
WA RRANTY
SCHEMATICS
S-155 Monaura l Record Circuit
S-15 8 Ste r eo Record C ir cuit
S -16 3 1 50 Hz E . O . M . Osc ill ato r
P-44 Century Pl ayback-Record B lo ck Diagram
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INTRODUCTION
Th
e
Centu
ry
Se
ri
es
of
cartridge
record
modul
es
are
intended
for
use
with
M
ode
l
4510-4525
cartridge
r
eproducers
.
The
record
modul
es
are
available
in
four
ba
slc
mode
ls:
4710 - mono r
ecord
,
with
stand
a
rd
1000
Ilz
stop
t
one
generato
r .
4715
-mono r
ecord,
w
it
h
added
150
H:z
EOM tone
generator
.
4720
-
st
e
reo
re
cord
,
with
sta
n
da
rd
1009
Hz
stop
tone
genera
t
or
.
4725 -
ste
r
eo
r
ecord
,
with
added
1
50
Mz
EOM
tone
generator
.
Thes
e
mode
ls
include
a r
eco
r
ding
h
~ad
to
conve
rt
the
appropriate
re pr
oduce
r
module
to
a r
ecord/p
lay
back
unit.
Refer
to
the
Rep
r
oducer
Operating
Manual
for
de
ta
ils
of
installat
i
on
and a
li
gnment
of
heads
.
Century
Se
ri
es
cartridge
equipme
nt
is
also
supplied
in
completely
assembled
and
tested
r
ecord/
pl
ayback
systems
as
fo
ll
ows
:
4610 - mono r
ecord/
pl
a y
wit
h
sta
nd
a
rd
l000Hz
generato
r
/detector.
4615 -
mo
no r
ecord/p
la y
with
added
150
Hz
!:OM.
gene
r
ator/detector.
4
620
-
stereo
r
ecord/p
l
ay
w
ith
stundard
l00qHz
gen
era
t
or/de
te
cto
r .
4
625
-
stereo
r
ecord/p
la y
with
added
150
Hz
EOM
generu
to
r/d
cteclor
.
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G:CNI:ML DCSCRIPTION
Th e recor d and rep roduce modu les are the same size , facilita tin g a variety of
mounting configura ti ons :
Dual table top with flip top cover
Tripl e rack mount (1 R/.P plus oplionul play only)
Quad custom cabinet (2 R/P or 1 R/P and 2 play on ly)
A ll electronics for audio a nd t one rec ording are on a single plug-in printed
circuit board , as is the power supply regul a tor. Thus , each model uses th e
snme basic p·.c . board, l ess unneeded circuit component s . Program bias l evd
can be adjusted through an access hole in the p.c . bourd cover.
A com bination of discrete and integrated circuits have been used in the record
circuits, to provide best possible per for ma nee . Record modu l es have separate
re gu l ated power supplies , and utilize a single switched bi as oscillator for
progr am and to ne recording circuits.
Three pushbutton-selected audio inputs are provided on the front panel of
each r ecord module, plus switch positions to check bias and ton e record l evels .
Audio inputs and Remote Control connections are made to the barrier strip at the
r ear of the module. /\n Encoder i np ut is also provided , to record AfSK or Touch
Tone data on the cue track for use in automatic logging systems .
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FREQUENCY RI:SPONSE:
NOISE:
DISTORTlON:
EQUA LI ZAT I ON:
AUDIO INPUTS :
METERING:
CUE SIGNALS :
BlAS
OSC ILLATOR:
REMOTE
CONTROL :
DIMENSIONS:
POWER :
WEIGH T:
SPECIFICATIONS
50-1 5 ,0 00 Hz+ 2db
55db or more be low saturation
r eco rdin g (mono)
52 db or more be l ow sa tur ation
r ecording {st ereo )
2% or l ess , r ecord- r eproduce at
NAB Standard Reference Level
NAB ( Adjustable)
3 selected by pushbuttons, balanced
bridging, -10 to +8 dbm
Progra m r ecord l evel, cue r ecord level,
bias
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NAB l kHz stop standard; 1 50 Hz
E. O. M. optional; Encoder input for Ar SK I
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68 KHz, sepa r ate switches and l evei
controls for pr ogram and tone recording
Pr_og r am r ecord , EOM r ecord
RecGrd and pla y back modules each
6"Hx · S3/4"Wx l 4"D
117 volts, 50/60 Hz ( available for
230 VA C on spec ial order )
R
eco rd module, 8 lbs .
Recor d/playback with dua l li d, 27 l bs .
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INST/\LLATION
UNP ACKING:
After r emov in g the equipment fr om the shipping container , carefu ll y inspect if for
shipping damage . If damage is discovered, make a written reque st to the carrier
for inspection , and r etain a ll cartons and fill ers . Th e carrier is responsible for
any damage incurred in shipping , but the claim mu?t be promptly filed by th e
r
ece iver.
ENCLOSURES:
Tabl e t op units a re shipped with lids inst a ll ed . However, Triple Rack Mounts
and Quad Cubinets are shipped sepa(ately from the r eco rd and pl ayback modul es .
Th e r ecord and playback modules are fa stencd together for use with the Dual Lid
and Triple Rack Mount. A 10-32 x 1/2" machine screw secures the two modules
tog ether at the upper rear inside edges . A cha'ssis tie tab is used at the top
front edges . If a record module is orde red separately , the chassis tab w ill be
supplied .
When ordered with the Triple Rack Mount , modu les w ill be supplied with sma ll
t abs fasten ed to the upper r ear edge of the p.c . board covers. After the modules
.
are in the rack mount, the screws sec uring the tabs shou ld be loos ened and
rc ti ghtened with the tab extending vertically so as to prevent th e modul es from
accident a ll y being pull ed ou t of the rack mount. The modules can be secured to
t he r ack adapter by turning th e l ocking latch screws clockwise . The se are
Phillips head screws loc at ed beneath each module cage .
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The re cord and pla yb ac k modu l es a re n ot ' faste ned t oge t he r wh e n u sed with th e
Qu ad Cabine t, due to th e ventilation separators a t t he fr o nt of the cabinet.
Ext e nd ed le ngt h cab l es are supplied so as to pe rmit considerable individual
mov eme nt of the r ecord or pl aybac k module .
If d es ir ed , th e modules can be sec ur ed to t he cabinet by means of ang le brackets
whi c h a tt ach to th e up pe r part of th e p .c . boa rd covers .
Th e r ecord modu le has a short cable te rmin a ting in an 8-pi n co n necto r which
plug s into the re pr oduce module .
The a- c cord of th e record modu le can be plugged in to the a ccesso ry outlet of
th e r eproduce modu le , if desired.
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I AUDIO & CONTROL CONNECTIONS
I
BARRIER STRIP PINS :
1.
Input #1 Left Channel+
2 . I
nput il Le ft Channel -
I 3 . Common Shield
I 4 .
Input #2 L ef t Channel +
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s.
Input #2 Left Channel -
6 .
Common Shie ld
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7.
Input #3 Left Channel +
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8.
Input #3 Left Channel -
9 •
Common Shield
I 10 .
Record Preset
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11.
Record Preset
1 2.
Record lamp
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13.
Input #1 Right Chann el +
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14.
Input #1 Right Channel -
15 .
Common Shield
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6.
Input #2 Right Channel +
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17.
I nput #-2 Right Channel -
18 .
Common Shie ld
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19.
Input #3 Right Channel +
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20 .
Input #3 Right Channel -
21.
Common Shield
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22.
Encod er Common
I 23 .
Encoder+
24 .
Common
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RI:CORD PLUG:
The 8 pin record plug (P3) carries logic circuits that can be used as status
indicators and fo r various remote contro l applications . The pin numbers
below are for the record plug.
1. Record Preset Line (-25 in run mode )
2 . - 25 VDC from
stop switch
3 . - 25 VDC stop/ready mode
4. -2 5' VDC run mode
5 . Common
6. EOM remote record - normally jumpered to pin 5 - cut jumper and connect
n.c. switch across pins 5 & 6
7. Spare (11 0 VAC if supplied with remote contro l)
8 . Spare (110 VAC if supplied with r emote control)
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RECORD PRESET:
E.O . M . RECORD:
RECORD LEVEL:
SOURCE SF.LECT:
OPf.RATION
This illuminated pushbutton switch turns on the record
circuitry . The t ape trans port must be stopped and with
a cartridge inserted before the record mode can be ac -
tiv ated . The .:;witch is li ghted when in the record mode.
The switch is al so used to record r:. 0. M. tones ( sec
below.)
In recorders so equ i pped , the 1 SO Hz end-of-message
tones are r ecorded on the cue track of the tape by
depressing the Record button while the tape is in motion,
E. 0 .M . tones can be applied in either the record or play modes .
This contro l adjusts the l eve l of audio to the record am-
plifi er . The material to be reco r ded should be auditioned
before recording, and the l eve l control set so that the VU
m eter (s) deflect to the edge of the r ed ar ea
I
but not into
it. If an audio console is used to feed the cartridge re-
corder , th e level cont r ol can be set u sing a tone or test
r ecord so that0VU on the conso l e·meter produces 0VU on
t he cart r idge meter . The contro l can then be ma r ked and
l eft at th e correc t sett i ng .
There are 3 audio inputs to the Century Se ri es r ecord
amp l ifier , selected by th e pushbuttons on t he front panel .
Two
buttons can be depressed simultaneously, allowing both
audio sources to be mixed into the . record amplifier .
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TEST
ru
NCTIONS:
Th
e
re
are
2 t
es
t
buttons,
marked
Tone
and
Bias.
The
Tone
button
is
used
to
verify
the
operation
of
the
l
000Hz
stop
tone
and
the
optional
150
Hz
E. O . M.
tone
generators
.
When
a
cartridge
is
started
in
the
re
co
rd
mode,
the
meter
pointer
should
swing
to
a
pproximatcly
100 on
the
scale
for
about
1/2
second
as
the
stop
tone
is
record
ed
on
th
e
cue
track
of
the
tape
.
Likewise,
depressing
th
e
Record
button
while
the
cartridge
is
running
shou
ld
produce
a
meter
deflection
to
10
0
as
long
as
the
button
is
held.
Readings
between
80
and
120
on
the
meter
scale
should
be
considered
normal.
On
stereo
recorders
only
the
l
eft
channel
meter
displays
th
e
tone
te
st
function
.
The
presence
and
level
of
bias
to
the
program
r
ecord
head
can
be
checked
by
depressing
the
Bias
button
with
the
system
in
the
record
mode
.
The
meter
should
read
approximate
ly
100
.
The
cor
r
ect
bias
level
assures
l
owes
t
nois
e,
distortion,
and
best
high
frequency
response
.
If
ne
cessa
ry,
the
bias
can
be
adjusted
by
moving
the
bias
control,
which
is
r
eached
thr
ough
an
access
hole
in
the
p.
c .
board
cover
.
On
stereo
recorders
there
are
separate
bias
control
s
for
each
channel.
T
he
bias
reading
has
been
factory
calibruted
for
use
with
Scotch
brand
156
tape
.
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RECORDING
PROCEDURE:
Good
r
ecordings
begin
with
prop
e
rly
e
rased
cartridges.
Slow
ly
pass
both
sides
of
t
he
cartridge
ac
r
oss
the
era
scr
,
th
e n
slow
ly
pu
ll
t
he
cartridge
away
to
a
distance
of
2
feet
or
mo
re
before
turning
off
t
he
eraser
power
.
This
wi
ll
prevent
gliches
from
being
"rec
orded
11
on
the
tape
due
to
th
e
collapsing
magnetic
fie
ld
around
the
erase
r.
Check
to
see
that
th
e
tape
heads
are
clean
.
If
not,
wipe
t
hem
clean,
using
alcoho
l
or
a
prepared
head
cleaning
solution
applied
with
a
soft
,
clean
cloth
or
cotto
n
swab
.
In
se
rt
the
ca
r
tridge
into
the
tape
tr
anspor
t,
then
start
and
stop
the
cartridge
once
or t
wice
befo
re
pushing
the
R
ecord
button
.
This
will
insure
that
the
tap
e l
oop
is
prop
erly
t
ensioned
and
is
guiding
correctly
across
th
e
heads.
This
procedure
he
l
ps
to
avoid
t
he
":;wishing
11
sound
th
at
is
of
t
en
presen
t
when
a
tape
cart
ri
dge
is
first
st
ar
t
ed
,
as
a
result
of
t
he
t
ape
not
having
been
cor
r
ectly
aligned
across
th
e
heads
when
the
recording
was
started
.
.
Depress
the
Record
bu
tt
on
to t
urn
on
th
e
re
co
rd
circuit
ry.
Th
e
switch
will
li
ght
indicating
a
"ready"
conditio
n .
The
tr
a n
spo
rt
can
now
be
sta
rt
ed
by
depressing
the
r
ight
side
of
th
e
Touchbar
swit
c h .
It
is
important
not
to
apply
audio
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un
ti
l
th
e ta
pc
is
ac
tu
a
lly
moving
,
otherw
i
se
th
e
cartridge
will
cue
out
with
r
eco
r
ded
audio
in
con
t
act
with
t
he
r
eproduce
h
ea
d .
This
wil
l
cause
o
moment
ary
bu
r
st
of
sound
Just
as
the
t
ape
s t
ops
.
It
can
al
so
cause
a
wow
at
t
he
ti
me
of
starting
th
e
cartridge
.
In
an
automation
system
using
2S
Hz
tone
sensing
for m
usic
tapes,
the
momentary
burst
of
very
l
ow
frequency
audio
(as
the
ta
pe
speed
accele
r
ates
from
zero
to
7
1/2
inche
s
per
second)
can
tri
gge
r
the
t
one
sensor
and
advance
the
syst
em
before
th
e
ca
rt
ridge
h
as
played.
It
is
good
o-pcrat
ing
practice
to
sel
ect
cartridges
that
are
only
s
lig
h
tl
y l
onge
r
th
an
the
announcement
to
be
rec
o
rd
ed
.
Thi
s
minimizes
the
cue
ou
t
time
which
means
more
effici
en
t
utilization
of
ti
me
during
r
eco
r
ding
and
playback
.
If
an
optimum
l
eng
th
ca
r
tridge
is
not
av
a
ilab
le
at
th
e
tim
e
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of
r
eco
r
ding
,
it
is
usu
a
lly
preferable
to
reco
rd t
he
announce
-I
ment
2 or more
times
on
t
he
same
cartr
id
ge
to
minimize
cue
o
ut
time
when
t
he
cart
ri
dge
ls
u
sed
on
the
air.
It
t
akes
on
ly
a m
inut
e
or
t
wo
at
th
e
ti
me
of
r
ecording
,
but
can
save
many
min
ut
es
for
harried
operato
rs
during
t
he
l
ife
of
t
he
announcement.
If
th
e r
eco
r
de
r is
eq
uip
ped
with
the
optiona
1
end
-
of-message
t
one
, t
he
E.0 . M
ton
e must
end
1
or
2
seconds
before
-
th
e
stop
t
one
begins
.
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If the .C . 0 . M . tone is applied in the play mode and
ovcrla ps the stop tone, it will partially erase t he stop
tone due to the presence of the cue r ecord bias. In an
automation system using a "maintained start" type of
control , e rr atic stop cueing can occur unlcs s the E. O . M.
and stop cues are separated, since the stop circuit in
t he cartridge trans por t will not function until a ft er the
E.O.M . t one has ended .
The E. O . M. tone can be any desired length , determined
by how lo ng the Record tutton is depressed . However , the
circuit is designed to produce a minimum tone length of
. 5 second, even if the button is only tapp ed. In most
automation systems t he beginning of th e E.0 . M. signal
starts th e ne.xt audio source , while continuing audio
fr om th e first (overlap audio switching}. The end of the
signal turns off audio from the first source . Therefore , it
is important to release the Record bucton af t er the
announcement has ended. The P.O int at which th e ton e
begins will determine the amount of overlap or ti gh tn ess of
th e program.
- 1 2-

www.SteamPoweredRadio.Com
GENERAL:
PRcx:;RAM BIAS:
ELECTRONIC ADJUSTMENTS ( See dwg. P-42)
The entire r ecord electronics is contained on a
single plug in printed circuit board. Program
bias can be adjusted through an acces s hole in
the p.c. board cover. To make other adjustments
it is necessary to remove the cover .
Requires a high impedance a-c voltmeter and a
signal generator or test reco r d.
1 . I nsert erased cartridge into transport .
2. Connect meter to ground and blue test point.
3 . Depress Record button momentarily.
4. Adjust R80 for a r eading of 64 millivolts .
5. Connect meter across reproducer barrier strip
terminal s 1 -& 2 (audio output) or observe playback
l evel on audio console meter .
6 .
Record a 1000 Hz tone, using an indicated record
l evel of 0 VU .
7 .
Adjust R80 for maximum playback level. Make
adjustment sl owly due to delay between record
and r eproduce heads.
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BIAS TRAP:
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8 . The blue test' point reading shou ld fall between
40 - 60 millivolts.
9. Repeat using Rl00, orange test point, and ba rri er
strip termina ls 4 & 5 ( ste r eo on ly) .
Pr og ram bias level can also be determined by alternately
recor ding 1000 Hz and 12, 000 Hz tones at -1 0 dbm and
a dju sting the bias control for the same playback level
at both fre quencies . U se a 620 ohm resistor across the
audio outp ut, unless it is already feeding a terminated
in put of an audio console .
Requi r es oscilloscope or hig h imp edance a-c volrmet er .
1 . In ser t er ased cartridge into t ran spo rt .
2 .
Conn ect meter between ground and junction of
C48 & 12.
3. Momen tarily de pr ess Record button .
4. Adjust C49 for minimum indi catio n of 68 KHz
bia s signal .
5. Conn e ct meter between g rou nd and junction of
C62 and L3 (st er eo only) .
6 .
Adjus t C63 for minimum indication of lOOKHz
bi as si gna l (stereo on ly}.
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www.SteamPoweredRadio.Com
PROGR/\M BIAS TEST CALIBR/\TJON:
Potentiometer R78 and Rl18 (stereo only) have
been factory set to give a readin g of 100 on the r eco rder
VU meter, when the program bias l eve l is correct.
PROGRAM REC ORD EQUALIZATION: R equ ir es a-c v0ltmeter and a s igna l generator
or test record. Tape heads should be correctly
aligned, and bias traps and record bias set. Playback
equalization should be adjusted for flattest r esponse .
1 . In sert erased cartridge into transport .
2. Connect meter across reproducer barrier scrip
te r minals 1 & 2 {audio output) or observe playback
l evel on aud io console VU meter. Put a 62 0 ohm
r esistor across the audio output unless it is
a lr eady feeding a t erm inated input of an au dio
console .
3. Dep r ess Reco rd button momentarily .
4. Record a 1000 Hz tone, using an indicated record
l evel of O VU
5 . Note the playback leve l on the meter and turn down
the Record Le vel control unti l the playback level
r eads 10 db l ower . ·
6. Record a 1 2,000 Hz tone, without changing the
r ecord l eve l setting . Adjust C4 1 to produce the
same playback level as step 5 .
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