Fostex G24S Service Manual page 28

2) Put all 24/16 tracks in the REC mode.
3) Set the core at T-2 (BIAS ADJ) to reach the peak level.
4) Then, adjust R210 (BIAS LVL) so that the level is lOOmVr.m.s.
4.3.8 Record Level Calibration
1) Put Dolby NR ON/OFF SW to OFF position.
2) Load the blank tape (A PEX 456) on the transport and apply an audio osdillator output
of IKHz, - lOdBV (0.3 V) to the INPUT jack on the recorder rear panel.
Also, plug in a level meter to the OUTPUT jack.
Taking TRACK 1 as an example, the connector number is " 1 " for both INPUT
ANDOUTPUT jacks.
3) Depress the RECORD TRACK 1 button, then, depress the RECORD and PLAY buttons
to put TRACK 1 in the record mode.
When thus in the record mode, the meter will indicate the input level regardless of the
position of the INPUT ON button. Check to see that the reading of this meter is OdB
± IdB.
4) After recording a certain length of IKHz, - lOdBV signal, rewind tape to the starting
point, put the transport in the PLAY mode and check the output level.
The INPUT ON switch must be at INDIV.
It is considered as a normal condition if the output level is - lOdBV ±ldB.
If it is off spec, correct by adjusting R207 (REC LVL).
Calibrate tracks 2 ~ 24/2 ~ 16 in the same way.
4.3.9 Overall Frequency Response
1) Put Dolby ON/OFF switch to " ON " position.
2) Apply IKHz and lOKHz,-35dBV signal repeatedly to the INPUT jack 1.
3) Put track 1 in the REC mode to record a certain length of the signal, rewind it to the start
point, and playback the tape.
Then, adjust R208 (REC EQ) so that the difference of the reproduce level between IKHz
and lOKHzis 0±ldB.
4) Apply signals from 50 through 15 KHz at -35dBV to the INPUT jack 1.
Record and reproduce the certain length of the signal. Confirm that frequency response is