TW LP4 S, User Manual

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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, Master potentiometer in 0 dB
position and switch LFA off. Connect an audio generator 1 kHz 0 dBm attenuator –80 dB to Mic 1 Input and
adjust TRIM
AL
in the Left Limiter amplifier to obtain 0 dBu (+4 dBu on VU metered mixers) at the Left
balanced output. Then adjust TRIM
M1
in the Left 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
to obtain 0 dB on the
Left modulometer. Repeat for Right output and Right modulometer.
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. Switch on the limiter and
adjust TRIM
LL1
in Left limiter amplifier until the level drops 0.5 dB. Repeat for Right output and Right limiter
trimpot.