Fostex G24S Service Manual page 29

as shown in Fig. 4.18.
If it does not fall within spec, correct it by slight rotation of R208 (REC EQ).
5) Put Dolby ON/OFF switch to " OFF " position.
6) Apply signals 40 through 18KHz at -lOdBV. Record and playback the certain length of
the signal.
It is considered as a normal condition if the frequency response from 40 through 18KHz is
within ±3dB against the IKHz reference level.
7) Calibrate 2 ~ 24/2 ~ 16 tracks in the same way.
4.3.10 Overall S/N easurement
1) Put NR ON/OFF switch to ON.
2) Upon completing checks up to Section 4.3.9 apply a IKHz, -lOdBV (0.3V) signal to
the connector panel INPUT jack 1, for example, and record the signal onto a blank tape.
Then, without stopping the tape, unplug the oscillator connected to the INPUT jack and
further record a length of no-signal tape.
3) Plug a level meter into OUTPUT jack 1 and playback the recorded signal section to meas ­
ure the noise level of the no-signal section against the IKHz reference level. Calculate
the difference between noise level and reference level, add 12dB to it and obtain the
ratio between peak recording level and noise level.
Specification: 84dB weighted, 71 dB unweighted G24S
82dB weighted, 69dB unweighted G16S
4.3.11
T.H.D.
easurement
1) Put NR ON/OFF switch to OFF.
2) To adjust TRACK 1, for example, apply a IKHz, -lOdBV (0.3V) test signal to INPUT