Feature: 1. Using high-quality accessories, accuracy assembly for stable performance 2. The product has strict quality control and quality assurance which can ensure the stability of the product 3. High-quality materials, fine workmanship, stable performance and long service life 4. The box has a built-in PTT control to keep the eliminater connected during transmission 5. The QRM canceller now allows adjustment of phase angle and amplification to cancel unwanted signals before they reach the front end of the receiver Specification: Item Type: HF Band Eliminater Kit Material: Printed circuit board Color: Green Model: None Principle: The QRM eliminater is inserted into the antenna feeder from trx without any other modification to the radio. The box has a built-in PTT control to keep the eliminater connected during transmission. However, an additional auxiliary receiving antenna is required, such as a 2 meters antenna or a wire only a few meters in the shed. The two antennas receive unwanted signals, resulting in different phases. The QRM canceller now allows adjustment of phase angle and amplification to cancel unwanted signals before they reach the front end of the receiver! It is based on a completely innovative concept and cannot be compared to normal "silencer" performance PCB: Approx. 73 x 85 x 1.6mm / 2.9 x 3.3 x 0.1in. Package List: 1 x HF Band Eliminater Kit