Operating instructions

1892 1211 - SR500 Receiver Operating Instructions - 2.10 / May 2006 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.

PIN NAME FUNCTION REMARKS

1 0V 0 volts common ground

2 RF I/P RF input 50O input

3 0V 0 volts common ground

Connector PL1 pin detail

PIN NAME FUNCTION REMARKS

1 +VIN positive supply +6.0V to +14.0V

2 0V 0 volts common ground

Connector PL2 pin detail

PIN NAME FUNCTION REMARKS

1 RSSI S meter output 0.5 - 2V signal strength indicator, 60dB range

2 SQF Squelch flag open collector output, ON (low) = no signal (15V max)

3 AUDIO AF output

250mV p-p +20% into 10kO

Note: The output audio is inverted with respect to the

ST500 (or similar Wood & Douglas product) audio

input.

4 DATA Data output open collector, no pull-up (14V max)

Note: The data output is inverted with respect to the

ST500 (or similar Wood & Douglas product) data

input.

5 +5V +5 volt supply

output

50mA maximum permissible current drain

6 0V 0 volts common ground

RS232 I/P serial

programming

input

RS232 programming input

Note: inverted TTL level data can also be used. If

not used, leave not connected, or connect to 0V

8 RB1

parallel

frequency

select

internal pull-up to +5V, active low

low < 0.8V

high > 4.0V

9 RB2

10 RB3

Connector PL3 pin detail