User manual

I/O BASIC SETTINGS ENG
Page 20
14.3 50 US / 75 US OUTPUT PREEMPHASIS SETTING (FM VERSION ONLY)
The frequency characteristic of analog L & R outputs (XLR male connectors) can assume either a flat frequency
response, or can follow a selected pre-emphasis curve, with or without subsequent de-emphasis.
When ‘flat’ mode is engaged, this yields a signal with a flat frequency characteristic, but with an output ceiling that
exactly follows the inverse of the pre-emphasis curve. Doing so, if the signal is again pre-emphasized in an external
stereo generator or exciter, the transmitted signal will have proper pre-emphasis and spectral protection.
The actual pre-emphasis time is indicated on the Pre-
emphasis menu.
If, for some reason, the unit is to be operated at a
preemphasis which is different to that as supplied, in addition
to the menu setting, you need to open the top cover and set
properly the jumpers CN 17 and CN 18 on the outside of the
I/O MPX board (left board), accordingly to the following
table:
ANALOG OUTPUT MODE MENU SELECTION ** JUMPER SETTING
Flat, fitting external 50 uS pre-emphasis 50uSec External CN 17 and CN 18 in 50 uS position
Flat, fitting external 75 uS pre-emphasis 75uSec External CN 17 and CN 18 in 75 uS position
Pre-emphasized, 50 uS 50uSec Internal No setting required
Pre-emphasized, 75 uS 75uSec Internal No setting required
14.4 LCD BACKLIGHT CONTROL
As factory preset, the LCD backlight is automatically turned off in the event the front panel controls (shuttle and buttons)
are left untouched for 5 minutes. If permament backlight is needed, move the jumper J9 located on the front panel board
towards the mother boards.
J9
display backlight Illumination always on
display backlight illumination activated by
keyboard