User's Manual
Table Of Contents
- 1. General Description
- 2. Installation and Operation
- 3. Options
- 3.1 T01 Programmable Channel Spacing
- 3.2 T02 Programmable CTCSS encoder/decoder
- 3.3 T03 Programmable DCS/CTCSS encoder/decoder
- 3.4 T05 Balanced and Isolated VF plus E&M
- 3.5 T06 Simplex Changeover Relay
- 3.6 T08 VF Delay
- 3.7 T09 300Hz Upgrade HPF Filter
- 3.8 T10 Power Save Mode
- 3.9 T11 Combined Options
- 3.10 T12 External Reference Oscillator Input
- 3.11 T13 Local Speaker, Mic Socket and Front Panel Mute
- 3.12 T14 Local Channel Change
- 3.13 T16 1PPM Frequency Stability
- 3.14 U69 Extended Temperature Range Verification
- 3.15 T19/26 Line Interface Board.
- 3.16 T29 Balanced and Isolated VF plus E&M
- 3.17 T31 Network Adapter
- 3.18 T34 Ethernet option
- 3.19 T36 Option - TX Ref Oscillator input and Modulator
- 6. MX800 Base Station Fault Finding Procedure
- 7. Appendices
- 7.1 MX800 Interface Connections
- 7.2 CN2 DB9 Female Monitor Connector
- 7.3 CN3 DB25 Female Digital I/O Connector
- 7.4 MX800 Specifications
- 7.5 Channel Select DIP Switch Settings
- 7.6 MX800 Model Number Configuration Guide
- 7.7 MX800 System Applications
- 7.7.1 Conventional base station/repeater
- 7.7.2 Link transceiver
- 7.7.3 Data transceiver
- 7.7.4 Paging transmitter
- 7.7.5 Trunking Base Station
- 7.7.6 Systems base
- 7.7.7 Repeater with Morse ID
- 7.7.8 Simplex base station
- 7.7.9 Duplicated base station
- 7.7.10 Power Save base station
- 7.7.11 Tone key base station
- 7.7.12 Voting base station
- 7.7.13 Simulcast base station
- 8. Superseded Technical Information
- 9. Drawings
Technical Manual Superseded Technical Information
8.1.3 PA Fault Finding Procedure
First do a visual check of all the components on the PA looking for any
damaged components.
Connect the input of the PA to signal generator with the RF output switched
off.
With PTT off measure the +13.8V supply at the collector of the output
transistor.
Key up the PA and check the supply voltages on the hybrid module. Refer to
your circuit diagram for test points.
Turn the supply voltage OFF and lift the RF output lead of the hybrid and
solder a flying lead to the lifted leg. Connect the earth of the flying lead to the
earth of the PA.
Connect the Flying lead to a power meter. Turn ON the supply voltage and
the signal generator RF output, PTT the PA and increase the generator output
whilst measuring the hybrid power output.
The hybrid may be faulty if it has an output of less than 5W.
The PA RF transistor may be faulty if the hybrid has an output power of
greater than 5W.
See section 9.1 for superseded PA Drawings document number
© SPECTRA ENGINEERING 2008 Revision 4.3.1B
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