Operating instructions

1892 1210 - ST500 Transmitter Operating Instructions- v2.12 / May 2007 3
CONNECTION
Connection to the unit is via PL1, PL2 and PL3 which plug directly into the user's own
equipment. The location of these connectors is shown in Figure 1 and detailed in the
following tables. (The unit is fitted with a 10 pin connector when parallel frequency select
facility is provided).
PIN NAME FUNCTION REMARKS
1 0V 0 volts common ground
2
TXE
transmit enable o/c = transmitter disabled
LOW <+0.5V = transmitter enabled
1K nom. internal pull-up to +Vin
3 DIGITAL I/P data input 0/+3V to 0/+12V, DC-coupled
4 ANALOGUE
I/P
analogue input 800 mV p-p, AC-coupled, for nominal
deviation
5 +5V
OUT
+ 5 volt supply output 50mA maximum permissible current drain
6 RS232 I/P serial programming
input
RS232 level programming input
Note: Inverted TTL data can also be used.
If not used, leave not connected, or
connect to 0V
7 0V 0 volts common ground
8 RB1
parallel channel select
(RB3 also readback)
internal pull-up to +5V, active low
low < 0.8V
high > 4.0V
9 RB2
10 RB3
Connector PL1 pin detail
PIN NAME FUNCTION REMARKS
1 0V 0 volts common ground
2 RF O/P RF output 50O output
3 0V 0 volts common ground
Connector PL2 pin detail
PIN NAME FUNCTION REMARKS
1 +VIN positive supply +6V to +15V
2 0V 0 volts common ground
Connector PL3 pin detail