Campbell Scientific RF310, RF312, RF313 Narrowband Radios - Manual (Page 49)

B-1
Appendix B. Alternate Base Station
Configurations
The basic base station consists of a computer and the RF310B Base Station. There are
other options for a base station including a portable base station, a phone-to-RF base
station, and a phone-to-RF base station with measurement capability.
B.1 The Portable Base Station
The portable base station is an aid in setting up a large radiotelemetry network,
or in trouble-shooting RF network communication problems. A portable base
station allows any of the field or repeater stations to act as a base station.
Therefore, to try any particular RF link, it is not necessary to travel to the fixed
base station.
Figure B-1 is a block diagram of a portable base station. The computer, with
PC208W installed, is the user interface to the RF network. Remember that the
"RF Path" designation will be changed often to test various RF links. The
SC532A is the interface from the laptop computer to the RF310M Modem.
The transformer on the SC532A should be cut off 6" up the cable. The two
leads on the SC532A should be stripped and tinned for connection to a battery.
Most laptops have a 9-pin RS-232 port, so a 9- to 25-pin RS-232 cable is
needed to connect the computer to the SC532A.
B.2 Phone-to-RF Base Station
When an RF network is a great distance from the desired place of data
collection, a phone modem can be used to call the RF base station. A
computer, with PC208W Datalogger Support Software, and a Hayes
compatible phone modem can call a phone-to-RF base station. The
configuration is shown in Figure B-2.
The Device Map in the Setup Window of PC2082 must include the following
communication path: COM Port, Phone Modem, RF Modem, Datalogger. The
phone number and RF Path need to be filled in to match your setup. The
PS512M Power Supply and Charging Regulator supplies 5 V to the RF310M,
supplies 12 V to the COM200 Phone modem and RF310 Radio, and acts as a
null modem between the COM200 and the RF310M. The PS512M and
CH512R need to supply 12 volts on Pin 8 of the 9 pin connectors. PS512M
with serial number less than 1712 require a power adapter, part number 10704.
CH512R serial number less than 1075 also require the same power adapter.
The RF310M and COM200 are both connected to a separate 9-pin port on the
PS512M. The RF310M Station ID at the phone-to-RF base station must be
255 to allow more than one field station to be called without terminating the
initial phone link. The RF310M in the RF310M-ME State recognizes Station
ID 255 as a command to answer the phone and hold the ring line high which
keeps the Modem Enable line high after the Ring from the phone modem has
quit.