ZHC518A-3000W/M2 Analog TV Transmitter
Overview:
This Transmitter is a high-standard, broadcast-grade cabinet-type all-solid-state analog TV transmitter with a modular structure, which is very convenient for maintenance. It uses a new software radio technology to achieve the TV modulation function; the use of international high-quality LDMOS high-power field effect tube to achieve RF amplification, the output power can be 3000W.
The TV transmitter is mainly composed of a TV modulation unit and an RF power amplification unit. Among them, the TV modulation unit uses the new FPGA + DDS to realize the software TV modulation function, while obtaining superior technical indicators while ensuring reliability and performance consistency; the RF power amplification unit uses international high-quality LDMOS high-power field effect transistors, Analog/Digital Compatible, stable and reliable.
The whole Transmitter adopts 19 "standard stainless steel case, suitable for all levels of TV stations.
Features:
● Analog TV exciter with new digital technology, superior performance, high reliability and good consistency.
● The main and backup exciter configurations can be used to reduce the stop rate (spare exciter and automatic switch are optional).
● With no video, over standing wave ratio, over power, over voltage, over current, over temperature and other protection functions to reduce equipment damage.
● Power control adopts closed-loop automatic gain control to ensure stable output power without drift.
● The power amplifier unit is composed of two independent 2000W power amplifiers. Each power amplifier uses three original imported high-quality long-life and large-volume axial fans in parallel, with large redundant air volume and good heat dissipation effect, so that the transmitter is in a low temperature state, which can extend the life of the transmitter.
● The 2000W power amplifier is installed in a 3U high 19-inch standard chassis, which is composed of four identical 500W power amplifier modules for low loss, high isolation and in-phase synthesis. The power redundancy design has a large margin and high reliability.
● The power amplifier module uses the latest high efficiency and high standing wave ratio LDMOS tube, adopts microstrip impedance conversion technology, simple and efficient, good consistency, easy maintenance and replacement.
● Using high-quality switching power supply, with over-voltage, over-current, under-voltage, over-temperature, short circuit, lightning protection and other protection measures, high efficiency, good voltage regulation range, strong ability to adapt to external power changes; and flexible N + 1 heat Plug-in configuration scheme, parallel current sharing centralized power supply. It can also be redundantly configured according to customer requirements.
● With intelligent network management and monitoring, with RS232 and TCP / IP communication interface.
ZHC518A-3000W/M2 Analog TV Transmitter Diagram
Technical Specifications:
Overall performances:
1. Operating frequency band: VHF / UHF
2. Image carrier frequency deviation: ± 300Hz
3. Output power: 3000W
4. Output impedance: 50Ω
5. Inter-modulation distortion: ≤-50dB
6. Useless emission: ≤-50dB inside adjacent channels;
≤-65dB outside adjacent channels
7. RF output interface: 7/8” Flange or 1-5/8” Flange
8. Power supply: three phase 380VAC
9. Cooling method: forced air cooling
10. Working environment temperature: -10~+45℃
11. Dimensions: 570mm(width) x 1360mm(height) x 850mm(depth)
12. Weight: 180Kg
Image performance:
1. Video input level: 1VP-P positive polarity
2. Video input impedance: 75Ω
3. Video in-band reflection loss: ≥35dB
4. Video input interface: BNC-K
5. Periodic clutter signal-to-noise ratio: ≥55dB
6. Continuous random wave SNR: ≥60dB (weighted),
≥55dB (un weighted)
7. Group delay: ±30ns
8. 2T square wave distortion: ≤1%
9. Distortion of brightness waveform: ≤1.2%
10. Non-linear brightness distortion: ≤3%
11. Differential gain DG: ≤±3%
12. Differential phase DP: ≤±3°
13. Color / bright gain difference: ≤1%
14. Color / bright delay difference: ±5ns
15. Modulation degree: ≤87.5%
Sound performance:
1. Sound / image carrier power ratio: -10dB
2. Sound carrier frequency deviation: ±200Hz
3. Audio input level: 0dBm ± 6dBm
4. Audio input impedance: 600Ω balanced or 10KΩ unbalanced
5. Audio input interface: XLR-K / BNC-K
6. Sound modulation capability: >±100KHz
7. FM signal-to-noise ratio: ≥70dB
8. Amplitude-frequency characteristic: ± 1dB
9. AM noise (no modulation): ≤-55dB
10. Internal carrier noise (100% modulation): ≤-50dB
11. Harmonic distortion: ≤0.3%
12. Maximum frequency deviation: ±50KHz
13. Pre-emphasis time constant: 50us
