ZETRON 640 DAPT XTRA, Installation And Repair Manual, Page: 85 / 210

Installation
025-9416 73
Remotely Located Transmitters
Most radio stations for wide area paging are located at a distance from the Model 640 paging
terminal. To accommodate this type of application, the station card can be programmed for
single- or multiple-site remote control. (Set in the Model 640 transmitter databases. See the
Model 640 Operating and Programming Manual , Part No. 025-9417, for details.)
The remote control is compatible with Motorola PURC® transmitter control shelf equipment or
a Zetron Model 66 Transmitter Control Panel. When so equipped, the Zetron station card can
directly drive a dedicated line or link transmitter with just a few wires.
Figure 37 illustrates the basic connections between the Model 640 and a link transmitter. In this
application, the colocated equipment sends pages out to the main paging transmitter by way of
RF or microwave link.
Tone Audio
PTT
Ground
Tx Audio HI/LO
Aux PTT NO
Aux COM
PURC® tone
signal leads
Model 640 with
PURC®-compatible
station output
Link
Transmitter
RF or
µ
wave
link
Zetron
Model 66
Link
Receiver
PURC

Paging
Transmitter
Figure 37. Remote Transmitter Connected by way of RF Link
Notes on Figure 37:
The following parameter settings are typical for connection to a Model 66 or a Motorola PURC® transmitter. In the
Model 640 database set:
Transmitter Key Type database (these value correspond to default “purc” record):
StaRmtCtrl = purc
ModeTime = 100 ms
DigDataPolarity = “0” for inverted data
Transmitter Key Up Control database:
KeyUpDelay = 420 ms HLGT (set to 120 ms for HLGT plus 300 ms per RF link delay
1 link = 420, 2 links = 720, etc.)
Figure 38 illustrates the basic connections between the Model 640 and a leased telco trunk. In
this application the remotely located transmitter (and controller) are directly connected to the
phone line and keyed by the TIP and RING pair.