User's Manual
Table Of Contents
- IMPORTANT NOTICE
- RESTRICTIONS ON USE
- PRODUCT CONFORMITY
- WARRANTY AND SAFETY INSTRUCTIONS
- TABLE OF CONTENTS
- INTRODUCTION
- 1 TECHNICAL SPECIFICATIONS
- 2 OPERATING VOLTAGE
- 3 SERIAL INTERFACE
- 4 USER INTERFACE
- 5 RF INTERFACE
- 5.1 Transmitter
- 5.2 Receiver
- 5.3 Priority RX/TX
- 5.4 Error correction
- 5.5 Error checking
- 5.6 User data whitening
- 5.7 Pacific Crest and TRIMTALK compatibility
- 6 TRANSPARENT DATA TRANSMISSION
- 7 SETTINGS
- 8 SW-RELATED COMMANDS AND OPTIONS
- 9 ACCESSORIES
- 10 APPENDIX A
- 11 APPENDIX B
SATELLINE-M3-TR1
User Guide, Version 3.0
32
6.3.3 TX delay
The radio modem can be configured to delay the beginning of a radio transmission by
1...65000 ms. This function can be used to prevent packet contention in a system, where all
substations would otherwise answer a poll of a base-station simultaneously. During this delay
data sent to the radio modem is buffered. Although the priority setting is "RX" , radio modem is
prevented to change over to receiving mode during the period of the TX delay.If this function is
not needed, the delay time should be set to 0 ms.
6.4 Tests
The radio modem can be switched to the Test Mode, where it will send a test packet on the
radio channel. The test packet is a normal data transmission, which can be used, for example,
when directing antennas during system installation.
When the test packet transmission has been switched on and saved by using the Programming
Mode, the transmitting radio modem needs only a power supply and an antenna.
If the channel spacing of the radio modems is 25 kHz, it is recommended to use 38400 bps as
a serial data speed of the receiving radio modem. In the case of 12.5 / 20 kHz channel spacing
the data speed of 19200 bps is recommended.
There are two Test Modes:
Short data block test
In this test mode the radio modem sends a short test string, which is preceded by a consecutive
number, and it ends to the line feed character. The short data block is repeated continuously
after 1 s break.
Short data block test is suitable for running data communication tests. Error-free reception of
data can be monitored using a suitable terminal program.
Example of a short data blocks:
00 This is a testline of SATELLINE 3AS radio modem
Long data block test
Long data block consists of character strings, which are repeated without breaks 50 s time
period. After 10 s break the test transmission is started again.
Example of a long data blocks:
00 This is a long testline of SATELLINE 3AS radio modem
Long block data test can be used for measuring Tx output power, standing wave ratio (SWR) of
the antenna system or received signal strength at Rx stations.