Unit 1 – Introduction Meridian 2.5 kW UHF Model T2500U Technical Service Manual TSM20-342 Rev.
Unit 1 – Introduction Contents Unit I Introduction 1. External Layout: Page 05 2. General technical descriptive: Page 06 3. Technical Characteristics: Page 08 4. Block Diagram: Page 09 Unit II IF Modulator 1. Audio and Video Modulator Page 02 2. Technical Characteristics: Page 04 3. Reference mask: Page 06 4. Front and Back panel: Page 08 5. Circuit Diagram MAV001: Page 10 6. Layout MAV001: Page 14 7. Parts List MAV001: Page 15 8. Power Supply: Page 18 9.
Unit 1 – Introduction Unit IV UHF 50W Amplifier 1. UHF 50W Amplifier: Page 02 2. Frontal and Back Panel: Page 03 3. Switched Power Supply +32V 14 A: Page 05 4. 50W UHF Amplifier Protections: Page 10 5. Power Detecting and Power Limiting Protection: Page 14 6. 2W UHF Amplifier: Page 16 7. 50W Output Amplifier: Page 19 8. 50W UHF Amplifier Circuit Diagram Page 23 Unit V 625W Amplifier 1. 625W Amplifier: Page 02 2. Frontal and Back Panel: Page 03 3.
Unit 1 – Introduction -4-
Unit 1 – Introduction -5-
Unit 1 – Introduction 1.
Unit 1 – Introduction 2. General Technical Descriptive: 2.1. IF Modulator (for transmitter): This is the input module. It is a professional audio and video modulator. The audio and video signals are applied to their respective input for the modulation process in IF (41 to 47 MHz]. The audio and video input impedances are 600 balanced Ohms and 75 unbalanced Ohms, respectively. 2.1.1. Video processing: The video signal passes through linearity correction circuits and then is applied to the 45.
Unit 1 – Introduction 2.3. Amplifier Levels: 2.3.1. Comment/Composition/Origin: The T2500U is composed for 4 625W amplifier modules combined through 3dB hybrid couplers. The final modules are drived by a 50W amplifier and 3 dB hibrid couplers as splitters. All the amplifiers are in solid state. 2.3.2. Protections/Signaling: Each 625W amplifier has a VSWR protection, temperature and a power limiting circuit.
Unit 1 – Introduction 3. Technical Characteristics: 3.1.
Unit 1 – Introduction 4.
