Fostex B-16 - Page 38

5.4 Record/Reproduce Amplifier Checks and Adjustments
Checking and adjusting the record/reproduce amplifiers can be speedily
and efficiently carried out by following the procedures below.
5-4.1 Calibrating the Dolby encode mode and meters
1) To calibrate TRACK 1, depress the RECORD TRACK 1 button, depress RECORD to
put TRACK 1 (CHAN 1) in the recorde mode without running the tape.
2) Plug in an audio oscillator output to the recorder rear panel INPUT 1 jack
' and apply a IKHz, -lOdBV (0.3V) signal.
3) Set the NR INT/EXT switch on the recorder rear panel to EXT, connect a level
meter to test point TP-1 and adjust REC CAL (R-101, lOKilB) so that the level
here is 390mV.
4) On completing the above adjustments, connect the level meter to OUTPUT 1 jack
on the recorder rear panel and check that the level here is -lOdBV (0.3V) ±ldB.
5) After checking the OUTPUT jack level, adjust METER CAL (R-102, 50KQB) for a
OdB reading on the recorder BAR GRAPH METER.
6) Calibrate tracks 2 a, 16 in the same way.
5.4.2 Calibrating the Dolby decode mode
1) Set the NR INT/EXT switch on the recorder rear panel to EXT and switch off
all RECORD TRACK buttons.
2) Playback the Reference Level Section of the Reproduce Alignment Tape,
3) Beginning adjustments from TRACK 1 (CHAN 1), connect a level meter to test
point TP-1 located near U2 upon the CHAN 1 PCB of the record/reproduce
amplifier, and adjust REP CAL (R-104, lOKilB) so that the level is 390mV.
4) After these adjustments, connect the level meter to the recorder rear panel
OUTPUT 1 jack and check that the level is -lOdBV (0.3V) tldB.
5) After check of the OUTPUT jack level, confirm that the meter reading is OdB,
±ldB.