Nuoptix Stereo Optical Recording System, Owner'S Manual

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NOISE REDUCTION CALIBRATION
Once again the noise reduction should not require adjustment once factory set
but the following procedure can be used if alignment is necessary. Check to be
sure the clipper trimpots R11 and R40 are turned fully clockwise. Rotate the
mode switch to the BIAS position. Adjust comparator CMP (R141) so that the
voltage at TP10 just switches from +15 to -15 volts. This allows the NR circuit to
follow signals that are at extremely low levels. Return the mode switch to
RECORD and set the input level to 100%. Adjust DEL NR (R136) so that the
voltage at TP9 just begins to increase. For best results R136 should be set just
before the increase occurs. This adjusts the level of the delayed signal fed back
to the NR peak follow circuit. This holds the NR circuit open until the end of the
delayed signal. Adjust NR GAIN (R171) for -0.1VDC at TP11. This adjusts the
NR gain or margin. Adjust AUD (R144) for a 7.60V peak to peak signal (2.68
VRMS) at TP12. Note there will be approxi0.2VDC at this point. This
sets the required amount of audio signal to be summed to the DC noise reduction
signal. (Note: The adjustment of R144 should be verified by photographic
development tests of tracks as described in the TRACK PLACEMENT AND SIZE
ADJUSTMENT section. The final setup requires that the modulated amplitudes
on the track be that given on page 16 for a given meter reading in the RECORD
position. R144 should be adjusted finally for that result.)
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