Jenn-Air 1892, 1300 manual Over-Air Symbol Rate AT S163 Note engineering function only

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4.17Over-Air Symbol Rate (AT S163) Note: engineering function only.

This command sets the over-air baud rate to enable the modem to be used with different radios and channel spacings. The command format is:

	AT S163=n<CR><LF>
Where:	n = 2	4800 symbols/sec
	n = 3	9600 symbols/sec
Default:	n = 2	4800 for 12.5kHz radios
	n = 3	for 25kHz radios
Read	AT S163?<CR><LF>
Read Return:	n<CR><LF>
Example:	AT S163=3<CR><LF> sets 9600 symbols/sec

4.18Preamble Period (AT S165) Note: engineering function only.

This command enables the number of preamble blocks (each block equals 6 bytes) that are transmitted before each data packet to be changed. This preamble allows for the rise time of the transmitter as well as the minimum number of blocks required by the receiver. This allows the system performance to be changed to enable the modem to be used with different transceiver equipment. The command format is as follows:

	AT S165=n<CR><LF>
Where:	n = 1 - 10 blocks
Default:	n = 2
Read	AT S165?<CR><LF>
Read Return:	nn<CR><LF>
Example:	AT S165=10<CR><LF> sets a preamble of 11 blocks

Note that a symbol period depends on the RF baud rate (as set by paragraph 4.17).

For the G-MAX radio at 9600 symbols per second n = 2.

For the SXn50 radio at 19200 symbols per second n = 14.

Hermes Operator Note

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Contents Specialist RF Designs Lattice House Baughurst Basingstoke UK RG26 5LPTel +44 0 118 981 Fax +44 0 118 981 Table Of Contents Received Signal Strength Indication Rssi AT S156Handshaking Operation During Transmit and Receive List of Tables List of FiguresIntroduction RS232 Connector Connections & IndicationsPin No Function Power Connector RF ConnectorFront Panel Indications Introduction Modem OperationData Transfer Modes RS232 Data HandlingReceive-to-Transmit Turnround Time ms DescriptionMAX List of Commands Command ModeOkcrlf Errorcrlf Command SyntaxParity ATB1 Baud Rate AT B0AT F?CRLF Format Mode AT FEngineering Test Modes AT OK CrlfRXX, Dxxxcrlf Software Version Information AT Command Mode Guard Time AT S154ATI9CRLF Centre Radio Frequency AT S155Rssi Level Level at RF Input dBm ±2dB Data Quality AT S158 Radio Channel AT S157Squelch Level Level at RF Input Squelch AT S159Output Power for 1W G-MAX Output Power for 2W G-MAX Transmission Power AT S160Power Level Output Power DBm Tolerance Nominal Level NominalTest Message Period AT S162 Channel Step Size AT S161Preamble Period AT S165 Note engineering function only Over-Air Symbol Rate AT S163 Note engineering function onlyFrame Synch Tolerance AT S166 Note engineering function only Invert Symbol AT S167Squelch Delay AT S168 Radio Frequency AT &F Restore defaults AT &Y8Save parameters AT &W AT &WCRLFATT?CRLF Display parameters ATT?Do not enter unless you wish to carry out a code load Ppppppppppppppppppppppppppppppppppppppppppppppppppppp RS232 Port Parameters Hardware SpecificationParameter Max SXn50 Radio SpecificationsEnclosures Mechanical SpecificationFront View of Casting Operating conditions Vibration SpecificationsType Approvals EMC