ADJUSTMENT POINTS
Gain and modulometer adjustment – Connect an AC voltmeter to the Left balanced line output.
Set channel 1 pan switch to L position, turn channel 1 fader fully clockwise, set Master at marked 0 dB
and switch LFA off. Connect an audio generator 1 kHz 0 dBm attenuator –80 dB to Mic 1 Input and
adjust TRIM
A1
to obtain 0 dBu (+4 dBu on VU metered mixers) at the Left balanced output. Then
adjust TRIM
M1
on Modulometer amplifier board to obtain 0 dB on the Left meter. Cut off the input
signal and switch on the Reference Generator . Adjust TRIM
RG
on Ref. Gen amplifier board to obtain
0 dB at the Left meter. Repeat it for Right output and Right meter, that turn up 4 / 4 switch and put
meter selector switch to 3–4 and repeat the setting for Channel 3 and Channel 4 outputs.
Limiter threshold adjustment – Connect an AC voltmeter to the Left balanced line output. Apply a
1 kHz signal until the AC voltmeter reading is at the level desired with limiter switched off. Move the
limiter switch in position LIMITER and adjust TRIM
L1
until the level drops 0.5 dB. Repeat it for Right
output and Right meter then turn up 4 / 4 switch and put Meter selector switch to 3–4 and repeat the
setting for Channel 3 and Channel 4 outputs.
