BFM 400 Microphones
Operating Instructions
6
BFM400 Operation Manual issue 7
2.2 H
ARDWARE
S
WITCHES
AND
S
ETTINGS
There are 8 settings that are only available when the inner panel is
removed. These are shown in Figure 2.2 (the PCB has been
detached from the panel for clarity).
Figure 2.2 — Hardware Settings (BFM401 shown)
Ident
Marked As... Function
A
3V3 / 10V
BFM401 parallel (and Processor Bypass All Call) only - see notes below
Used to set Access and Access Line Monitoring Level, must match
access input used.
B
S / P
BFM401 only - see notes below
Fit links in "S" position to use Serial RS485 Communications *
Fit links in "P" position to use Parallel Communications
C
Gain / Limiter SW1.1 - Set to ON to increase the gain by 15dB
SW1.2 - Set to "ON" to enable the limiter
D
SURV Level
Sets the 20KHz surveillance level used to monitor the microphone
capsule
E
O/P Level
Sets the Output level
F
IND Level
Sets the Indicator sensitivity (factory preset)
G
A-DC
Enables audio output DC monitoring, set to MON to enable
monitoring. This option must also be enabled in configuration
H
LK3
Make link if a "Bypass" switch is fitted
I
LK2
Make link to connect "BYPASS" output to +V IN.
Can only be used if Bypass switch is not fitted.
N
OTE
: Monitoring of the Access Line is only applicable to the BFM401
when it is set to "Parallel" Mode or multi-zone BFM microphones with a
Bypass "All Call" switch fitted. Monitoring is acheived by placing a
Zener Diode between the Access Line and 0V.
N
OTE
: * The Factory Default setting for BFM401 is "S" position for
"Serial" operation.
