Figure2 Dolby decodermeasurern,entpoints
Playback,azimuth
Playback,height
Record,
azimuth
Record,height
Figure3 Adjustmentsfor the heads
Azimuthadjustment,
playback
head
- Inserta Tandberg
test cassette
No. 23 or a
standardazimuth
cassette.
- SettheMonitor button to Tape
andconnecta
voltmeter to each channel of the OUTPUT
sockets.
- Press
the Play button. Adjust the playback
azimuth screws
shown in Figure 3 to obtain
maximumreadingon eachchannel.
Playback
level
- Insert
testcassette
No. 24.
- Connect
a voltmeterto each
channel
of the
Dolby decoderoutput shown
in Figure
2.
- AdjustthePLAYBACKLEVEL pots.
Rl19 and
R219until you read775mV on each
channel.
Levelmeteradjustment,
playback
- InsertTandbergtestcassetteNo. 24.
Whenthe playback
leveliscorrect,adjustthelevel
meterto 0 dB with PLAYBACKMETER Rl14
andR214.
Azimuth and height,record head
- UseMaxell UD XL I or an equivalent tape.
- Applf' 1000 Hz to the INPUT sockcts
both
channels.
- Set the Monitor button to Tape and connect a
voltmeter to the OUTPUT socketsboth
channels.
- Press
the Record button and turn the two record
head height screwsshown in Figure 3 by equal
amounts (the samenumber of degrees)to obtain
the maximum reading on both channels
of the
OUTPUT sockets,or the best compromise.
- Adjust the azimuth (10 kHz) and the height
alternatively, until the head sitscorrectly.
- Azimuth can alsobe adjusted with the built-in
control oscillator(10 kHz).
NOTE! The record height screws
must be adjusted
by equal amounts to ensure that the head paral-
lelism doesnot change.
Overall
frequency responsewith Type I Tape (bias)
- Set the Monitor button to Tape.
- Apply 1000 Hz from the signalgeneratorto one
of the inputs.
- Reducethe levelatthe signal
generatorby 35 dB
or reduce the levelby a similar amount on the
Input Level controls.
- Press
the Record button, and adjust the BIAS
ADJ. TYPE I TAPE, C1502andCl602 to obtain
maximum readingat the outputs.
- Sweep the audio generator throush the full fre-
quency rangeand check that the response
curve
is correct.
- If necessary,
adjust the curve with C1502 and
C1602 to obtain the correctresponse,
t 3 dB,
30 to 18000 Hz.
-'.\
Dolby decoderoutpul
Left channel
meas,
point
Or measure
on 81303 Right
channelmeas.
point
Or measureon R1403
i^
..^O
o^v^
^Va
.J n.':
\ -v/-
o<-o
^Biasadjustments
