Date printed: 24.01.12
64
D21m System
6.3.12 BCd dTMF / GlITS / BlITS / Minimixer Cards
(Details:
www.bcd-audio.co.uk)
The BCD 100421 card is designed to electrically and mechanically fit into
a Studer D21m I/O frame and is one slot wide. It is based around an FPGA
which embeds a Fractional DSP processor designed by BCD Audio.
The three versions of the card currently available are only differing by their
firmware.
The card consumes less than 0.5 W. The front panel LEDs are kept deliberately
dim in order to minimise supply current.
DTMF Version
This card is used to detect DTMF tone on up to 16 incoming lines and will
generate corresponding, internal GP output signals when DTMF 1 is detected.
The relevant front panel LED also glows when the DTMF tone is present. In
the basic mode the card will offer 16 output ports (as seen by the console), i.e.
destinations to which the operator should route remote lines that are named
‘DTMF 1-16’ in the configuration GUI. 16 corresponding GP inputs will
automatically appear in the configuration GUI’s ‘GPInputs’ page
.
These may
be connected to logic gates and key LEDs for status display on the OnAir
desk.
The basic concept is that a reporter in the field can gain attention of the studio
by pressing the number 1 key on their phone, and the relevant GPI is displayed
on the console surface via custom logic. An AGC system is also implemented
so that loud signals do not overload the detectors, and low-level signals are
detectable.
If required, DIP switch 1 may be set to ON to enable internal tone generators.
In this mode the card will also generate 8 output channels (to the console).
Note:
Changing this DIP switch will require the D21m frame
RECONFIG
key
to be activated. The mapping of the ports will change, possibly requiring
changes to the desk configuration. Switches no. 2 to 8 are not used.
Card outputs (console inputs) 1 and 2 provide 1 kHz GLITS tone at
–18 dB
FS
. DTMF #1 tone is provided on outputs 3 and 4. The DTMF tone is
697+1209 Hz at –21 dB
FS
.
DIP Switch 1
Option
ON GLITS and DTMF tones on
OFF GLITS and DTMF tones off
DIP Switches 2-8 are not used.
