Philips LBB 1330, Instructions For Use Manual

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5.7 Tone Control Card - TCC LBB 1357
Eurocard 10 x 22 cm with ‘a b’ connector (2 x 32) containing 4 individual tone control circuits with bass
and treble correction (+/- 10 dB), gain correction (+/- 10 dB), and an additional input for a splitter
function. All controls are screwdriver preset potentiometers.
In situations where clarity of speech is vital, and room acoustics make this difficult to obtain, Tone Control
Card LBB 1357 (TCC) is a very useful asset.
The unit has 4 independent tone control circuits, each having individual inputs and outputs. Each tone
control circuit gives separate bass and treble amplification and attenuation to a maximum of 10 dB.
As well as the 4 independent inputs, the TCC has an extra input which acts as a splitter. This ‘common’
input allows all 4 inputs to be fed by a single source, instead of the 4 independent ones. This is particularly
useful when several amplifiers are required to operate from 1 matrix output.
At the input of each circuit is a screwdriver preset control, adjusting the gain from -10 to +10 dB. The unit
will accept a balanced or unbalanced source without any loss of sensitivity.
The TCC has several different applications within an SM40 system, and operates effectively between any or
all of the following:
■
Matrix group outputs and amplifier inputs;
■
Input Cards (IPC) outputs and Matrix Card (MC) inputs;
■
Auxiliary sources (background music player, etc.) and MC inputs.
Because it is not controlled by the Central Processor Card (CPC), the amount of TCCs used in a system is
limited only by rack space and the amount of d.c. power available. In a ‘maximum’ system, of 64 outputs,
where TCCs are used between matrix outputs and amplifier inputs, a total of 16 cards would be used.
4 red LEDs are mounted on the circuit board, each of which switches on when its associated circuit reaches
its nominal output signal level of 0 dBV.
Two green LEDs advise that adequate supply voltage is present.
5. SM40 MODULES
5-27
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