Bird Technologies 3128A - Manual (Page 24)

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Figure 7 Interlock Connector
Using Remote Reset & Auxiliary DC
Remote reset can be used to wire a reset switch in a convenient location. Actuating the switch will reset the alarm con-
dition after the error has been corrected.
The reset input can be jumpered to ground so that the alarm will clear automatically when the reflected power
drops below the set point.
Auxiliary DC, (9-16 VDC @ 1A), can be used to power the Wattcher Unit.
Connection to these features is achieved through a four-terminal Screw-Clamp plug connector.
Figure 8 Remote Reset Auxiliary DC Connector
Meter Scales
Both the forward and reflected meter faces have triple-range scales. The full scale value shown on the element cap
determines the power scale to be read.
Alarm Condition
If the reflected power reading reaches the trip level, (for longer than 50ms) the buzzer will sound if enabled, the
alarm LED will flash, and the interlocks will be active. This condition will continue until the condition has been cor-
rected and the reset button is pushed.
Determining VSWR
The forward/reverse RF power ratio is readily calculated from the readings, and VSWRs may be determined from the
following figures. Following the vertical and horizontal grid, determine intersection of forward and reverse power
values. Slanted lines passing closest to this point indicate VSWR.