background image

6

 

MHX-920 Operating Manual: 

Glossary

 

 

 

 

 

 

 

 WARNING

:   

Qualified and experienced 
personnel must carry out the 
installation, removal or 
maintenance of all antenna 
components.

Once the equipment is deployed, you can verify the signal strength by 
entering into Command Mode and reading Register S123.  This register 
provides the average signal strength in dBm.  The minimum strength for 
communication is roughly -108dBm.  For consistent reliable 
communication, you should try to deploy the equipment such that signal 
strength exceeds -95dBm. 

 

3.2  Antennas and Cabling 

This section describes the recommended procedure for installing cabling 
and antennas for use with the MHX920 module. 

3.2.1 Internal 

Cabling 

The most common method for installing the module is to run a cable from 
the module’s MCX connector to a reverse TNC bulkhead connector on the 
chassis of the equipment as shown in Figure 3.  This cable can be purchased 
from Microhard Systems. 

 

 

Figure 3 Suggested Internal Cabling

   

Cable losses are negligible for the short piece used within the chassis.  
Additional losses up to 0.5 dB may be present in the MCX and Reverse 
TNC connections. 

RG316 Cable

with MCX male

connector

and Reverse TNC

bulkhead

connector

Reverse TNC Connector

MCX female connector

MHX920

 

Summary of Contents for MHX-920

Page 1: ...MHX920 900 MHz Spread Spectrum OEM Transceiver Revision 0 10 January 9 2006 17 2135 32nd Ave N E Calgary Alberta T3K 4Z4 Phone 403 248 0028 Fax 403 248 2762 www microhardcorp com Model MHX920A Microh...

Page 2: ...IONAL WARRANTY Indemnification The Purchaser shall indemnify Microhard Systems Inc and its respective directors officers employees successors and assigns including any subsidiaries related corporation...

Page 3: ...d antennas Antennas not listed in the tables must be tested to comply with FCC Section 15 203 unique antenna connectors and Section 15 247 emissions WARNING MAXIMUM EIRP FCC Regulations allow up to 36...

Page 4: ...ights ii MHX920 Regulatory Requirements iii CONTENTS IV 2 GENERAL 1 2 0 PRODUCT OVERVIEW 1 2 1 OUTPUT POWER LEVEL 2 3 INSTALLATION 4 3 0 OVERVIEW 4 3 1 ESTIMATING THE GAIN MARGIN 4 3 2 ANTENNAS AND CA...

Page 5: ...exempt band of the radio spectrum1 this means that it can be used without access fees such as those incurred by cellular airtime a serial I O data port with handshaking and hardware flow control allo...

Page 6: ...ry low power levels so it is recommended that the lowest power necessary is used using excessive power contributes to unnecessary RF pollution Ideally you should test the communications performance be...

Page 7: ...MHX 920 Operating Manual Chapter2 General 3...

Page 8: ...ween a transmitter receiver pair The number can be calculated based on knowledge of the equipment being deployed The following four factors make up a system gain calculation 1 Transmitter power user s...

Page 9: ...een system gain and path loss Referring to the same example suppose the path loss is 100 dB the gain margin would be 40 dB which is more than adequate for reliable communication Path loss is a very co...

Page 10: ...2 Antennas and Cabling This section describes the recommended procedure for installing cabling and antennas for use with the MHX920 module 3 2 1 Internal Cabling The most common method for installing...

Page 11: ...and any person when the device is in operation Surge Arrestors The most effective protection against lightning is to install two lightning surge arrestors one at the antenna the other one at the inte...

Page 12: ...t If the equipment is in a fixed location and is to communicate with only one other unit also in a fixed location then a Yagi antenna is suitable Choose a Yagi with enough gain to ensure adequate gain...

Page 13: ...he maximum power setting of 30dBm Example 2 What is the maximum power the MHX920 can be set to comply with FCC and IC given the following equipment given a Yagi Ant Gain 12dBd and cable and connector...

Page 14: ...Directional Antenna Bluewave RPTNC Pigtail MHS031501 9dBd 900MHz Yagi Directional Antenna Antenex RPTNC Pigtail MHS031441 10dBd 900 MHz Yagi Directional Antenna Bluewave RPTNC Pigtail MHS031451 11dBd...

Page 15: ...MHX 920 Operating Manual Glossary 11...

Reviews: