Campbell Scientific RF401-series and RF430-series Spread Spectrum Data Radios/Modems - Manual (Page 56)

Appendix B. Advanced Setup Menu
to 3, the transmitting radio will send the same packet up to 3 times; each time
looking for an ACK packet back from the receiving radio. If it does not
receive an ACK packet after sending the packet 3 times, the transmitting radio
will increment its Number of Retry Failures count. If a radio is configured to
do retries, it will produce an ACK packet for every RF packet that it receives,
addressed to it, that has a valid CRC. If 0 retries are configured, the receiving
radio will simply throw away any packet that fails the CRC. This reading is
cleared upon exiting Setup Menu or cycling radio 12 V power.
B.3 Received Signal Strength
Beginning with SW Version 6.420 the radios provide a means of knowing the
signal strength of the last packet received, addressed to it, that had a valid
CRC. To see this reading enter the radio’s Setup Menu /Advanced
Setup/Radio Parameters/Radio Diagnostics menu. RSS readings are cleared
upon exiting the Setup Menu or cycling the radio’s 12 Volt power.
The RSS reading is a relative signal level indication expressed in dB (decibels).
Readings may vary up to 10 dB from radio to radio for a given received signal
level. The weakest signal reading is around 25 dB and the strongest signal
reading is near 86 dB. Although the RSS readings are not absolute, they will
be of value in such activities as:
• determining the optimal direction to aim a yagi antenna
• seeing the effects of antenna height, location
• trying alternate (reflective) paths
• seeing the effect of seasonal tree leaves
B.4 Advanced Setup Standby Modes
The Standard Setup menu selections should fill the majority of user needs. The
following information is given in case you need to program a non-standard
standby mode.
The Standard Setup menu selections do not correspond with Advanced Setup
menu entries. For example: selecting a “3” in the Standard Setup menu selects
(< 2 mA 1 sec Cycle) whereas entering a “3” in the Advanced Setup menu
selects (< 4 mA 1/2 sec Cycle).
B-4