R.V.R. Elettronica PTX-LCD, Руководство пользователя

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PTX-LCD
49 / 58 User Manual Rev. 2.3 - 18/07/07
D2
D1
JP8
JP11
JP10
JP9
JP12
JP3
JP2
Figura 11-6
11.3.1 Adjustments, settings and indicators
D2 On: negative power supply voltage present
D1 On: positive power supply voltage present
JP3 3-5, 4-6, 9-11, 10-12 no attenuation con channel L
1-3, 2-4, 7-9, 8-10 12 dB attenuation on channel L
JP2 as JP3, for channel R
JP8 1-2 no gain on channel SCA2, 2-3 20 dB gain
JP11 1-2 input impedance for channel MPX_U 50 Ohm, 2-3 10 kOhm
JP10 1-2 no gain on channel SCA3, 2-3 30 dB gain
JP9 1-2 no gain on channel SCA1, 2-3 20 dB gain
JP12 3-5, 4-6 no attenuation on channel MPX
1-3, 2-4 12 dB attenuation on channel MPX
RV7 Adjustment of the MPX monitor output
11.4 Coder
The coder card is located above the audio motherboard between the audio input
section and the PLL/Driver board.
Two versions of this boards are available, the Stereo one (Fig. 11-7) and the
Mono/MPX one(Fig. 11-8). The only difference between a Stereo PTX-LCD and a
Mono/MPX one resides in the kind of coder module.
On this board, depending on the version, there are the low-pass filters, the
preemphasys circuits, the stereo coder and the clipper circuit, that can be included
or excluded via software.