Motorola Mth500 Basic 6802963c65 Manual

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MTH500 Portable Radio Basic Service Manual- OVERVIEW
CHAPTER 1
OVERVIEW
To achieve a high spectrum efficiency, the MTH500 uses digital modulation tech-
nology and sophisticated voice-compression algorithm. The voice of the person 
speaking into the microphone is converted into a digital bit stream consisting of 
zeros (0) and ones (1). This stream is then modulated into a radio-frequency (RF) 
signal, which is transmitted over the air to another radio. The process is called dig-
ital modulation....

OVERVIEW:  Voice Compression Technology
2
Voice Compression Technology
Voice is converted into a digital bit stream by sampling the voice at a high rate 
and converting the samples into numbers, which are represented by bits.
Voice compression reduces the number of bits per second while maintaining the 
voice at an acceptable quality level. The MTH500 uses a coding technique called 
ACELP (Algebraic Code Excited Linear Prediction). The compressed voice-data 
bits modulate the RF signal.
 Description...

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MTH500 Portable Radio Basic Service Manual- OVERVIEW
Transmitter Path Description
The transmitter circuitry includes a linear class AB Power Amplifier (PA) for the linear modulation of the
MTH500. It also includes a novel cartesian feedback loop to enhance its transmitter linearity and reduced splat-
tering power into adjacent channels. 
The transmitter path consists of a novel cartesian feedback loop that contains the forward and loop feedback paths.
The forward path includes the low noise ODCT...

OVERVIEW:  Description
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MTH500 Portable Radio Basic Service Manual - TEST SETUP & TESTING
CHAPTER 2
TEST SETUP & TESTING
Any level 3 repairs can deeply affect the performance of 
the MTH500 radio and may cause a new tuning proce-
dure. This tuning procedure can be applied by certain 
authorised Motorola depots where the appropriate 
TEST & TUNE EQUIPMENT is available.The appropri-
ate TEST & TUNE EQUIPMENT is a special automated 
test equipment which is only available at some Motorola 
factories and Motorola repair centers....

TEST SETUP & TESTING:  Typical Test Setup
6
Typical Test Setup
Figure 1.  Typical Test Setup
      
IFR 2968
MTH500
Battery
Eliminator
(WALN4097)
Power
Supply Antenna Adapter
Assembly
(FLN9659)
RF CableN-Type RF
Connector
3.8 V 

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MTH500 Portable Radio Basic Service Manual - TEST SETUP & TESTING
Test Check List:
The following table summarises the required test setups.
No.Test 
NameTest SetupRadio SetupTest ConditionsLimits
1. Base Sta-
tion Regis-
tration
Traffic             
Channel390.125 MHz
422.0125 MHz 3605
880TETRA 380+OMS for R1
TETRA 410MS for R2
Control            
Channel390.125 MHz
422.0125 MHz3605
880TETRA 380+OMS for R1
TETRA 410MS for R2
Time Slot 3
Country Code 753
Network Code 2361
Base Color 1
Location Area 22...

TEST SETUP & TESTING:  Typical Test Setup
8
Receiver Tests
1.  Simulate Base Station (registration) 
2.  RSSI
Transmitter Tests
1. Power Burst (Control Range)
2. Power Profiles
3. Tx Burst Timing Error
4. Vector Error RMS and Peak
5. Tx Frequency Error
Call Processing Tests
1. Talk Back
2. Call to Mobile
1KHz Test 
Signal
Group Mode-50dBm
5. Call 
Processing 
Call to Mo-
bile
Private 4 digit random 
number & “Send”28-32dBm
RF Gen Level 
Burst Power-90dBm 28-32dBm
Timing Error 

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MTH500 Portable Radio Basic Service Manual - TEST SETUP & TESTING
Duplex Test
1. Digital Duplex Test (Tx)
 
Measurement Capabilities: 
Bar charts (Tx Power, Freq. Err, Vector Rms.), Spectrum Analyser, Power Ana-
lyser, Vector Analyser, Vector Diagrams
How to Configure the IFR 2968 Setup
Perform the following steps to configure the IFR 2968 with the radio set:
1. Turn ON the IFR.
2. Press “Systems” Mode Key (wait until the digital system is initialised).
3. Press the “Tetra Mobile” soft key.
4. Press...

TEST SETUP & TESTING:  Typical Test Setup
10
13. Press “Min Rx Level” soft key. Thereafter, enter “-110dBm” and press “Min 
Rx Level” soft key.
14. Press “Max Tx Level” soft key. Thereafter, enter “30dBm” and press “Max 
Tx Level” soft key.
15. Press “Access Parameter” soft key. Thereafter, enter “-53dBm” and press 
“Access Parameter” soft key.
16. Press “Test Mode” soft key. Press “Enable” soft key.
17. Press “Base Service” soft key and “Supported” soft key.
Note: You are entering base services setup....