Jenn-Air 1300, 1892 manual Introduction

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1INTRODUCTION

This document describes the operation of the Wood and Douglas Hermes Radio Modem.

The Hermes modems provide a transparent data link for a wide range of applications. The internal modem can be used with a range of Wood & Douglas RF products to give great choice in the operating frequency and transmit power. Two enclosure types are available to suit different applications.

The Hermes uses 4-Level Frequency Shift Keying (FSK) technology to achieve a RF link data rate of 19,200 baud in a 25kHz channel spacing and 9,600 baud in a 12.5kHz channel spacing.

One of the radio transceivers (the G-Max family) used inside the Hermes is designed for harsh environments and operates over a wide temperature range and a high vibration environment.

The standard Hermes is fitted with the SXn50 range of transceivers. This family has products at VHF, UHF and 868MHz, with a maximum transmit power of 500mW.

Hermes Operator Note

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Contents Lattice House Baughurst Basingstoke UK RG26 5LP Specialist RF DesignsTel +44 0 118 981 Fax +44 0 118 981 Received Signal Strength Indication Rssi AT S156 Table Of ContentsHandshaking Operation During Transmit and Receive List of Figures List of TablesIntroduction Connections & Indications RS232 ConnectorPin No Function RF Connector Power ConnectorFront Panel Indications Modem Operation IntroductionRS232 Data Handling Data Transfer ModesReceive-to-Transmit Turnround Description Time msMAX Command Mode List of CommandsOkcrlf Command Syntax ErrorcrlfBaud Rate AT B0 Parity ATB1Format Mode AT F AT F?CRLFOK Crlf Engineering Test Modes ATRXX, Dxxxcrlf Command Mode Guard Time AT S154 Software Version Information ATATI9CRLF Centre Radio Frequency AT S155Rssi Level Level at RF Input dBm ±2dB Radio Channel AT S157 Data Quality AT S158Squelch AT S159 Squelch Level Level at RF InputTransmission Power AT S160 Output Power for 1W G-MAX Output Power for 2W G-MAXPower Level Output Power DBm Tolerance Nominal Level NominalChannel Step Size AT S161 Test Message Period AT S162Over-Air Symbol Rate AT S163 Note engineering function only Preamble Period AT S165 Note engineering function onlyInvert Symbol AT S167 Frame Synch Tolerance AT S166 Note engineering function onlySquelch Delay AT S168 Restore defaults AT &Y8 Radio Frequency AT &FSave parameters AT &W AT &WCRLFDisplay parameters ATT? ATT?CRLFDo not enter unless you wish to carry out a code load Ppppppppppppppppppppppppppppppppppppppppppppppppppppp Hardware Specification RS232 Port ParametersRadio Specifications Parameter Max SXn50Mechanical Specification EnclosuresFront View of Casting Vibration Specifications Operating conditionsType Approvals EMC