4Watt UHF TV linear amplifier

That Circuit is a UHF TV linear amplifier for small TV transmitters with output around 100-200mW. The transistor BGQ136 comes with SOT-122 case has gain of 13dB at 800MHz. So with input 100mW you get 2W output and for 200mW you get 4W. More: Do not exceed that or you will start to get a bad distorted picture! Feed with 25 Volts/3Amps. Use a really big heatsink.

The described circuit is a UHF TV linear amplifier designed specifically for small television transmitters, capable of delivering an output power range of approximately 100 to 200 milliwatts. The core component of this amplifier is the BGQ136 transistor, which is housed in a SOT-122 package. This transistor exhibits a voltage gain of 13 dB at a frequency of 800 MHz, making it suitable for UHF applications.

When the amplifier is supplied with an input power of 100 mW, it is capable of producing an output power of 2 watts. Similarly, with an input of 200 mW, the output power can reach 4 watts. However, it is crucial to adhere to these input power limits; exceeding them can lead to signal distortion, resulting in poor picture quality.

The amplifier requires a power supply of 25 volts and a current rating of 3 amps to operate effectively. This power requirement indicates that the circuit is designed for higher efficiency, allowing it to maintain linearity and minimize distortion during operation.

Thermal management is a significant consideration in the design of this circuit. Due to the power levels involved, it is essential to use a sufficiently large heatsink to dissipate heat generated during operation. Inadequate cooling can lead to thermal runaway conditions, potentially damaging the transistor and degrading performance.

In summary, this UHF TV linear amplifier circuit is tailored for small transmitter applications, featuring the BGQ136 transistor, a specified gain, and strict operational guidelines regarding input power and thermal management. Proper implementation of these specifications will ensure optimal performance and reliability in broadcasting applications.That Circuit is a UHF TV linear amplifier for small TV transmitters with output aroun 100-200mW. The transistor BGQ136 comes with SOT-122 case has gain of 13dB at 800MHz. So with input 100mW you get 2W output and for 200mW you get 4W. Do not exceed that or you will start get bad distorted picture! Feed with 25 Volts/3Amps. Use Really big heatsink. 🔗 External reference