The Second Hand Datong FL-3 Multi-Mode Filter is a versatile external audio signal filter designed to enhance the listening experience for users of scanners, shortwaves, and ham receivers. This device features automatic and manual notch filters and adjustable low- and high-pass filters, allowing for precise audio control. It has three variable controls and five push buttons, enabling users to easily switch between different operating modes.

The operating modes include Power on/off, Auto notch on/off, SSB + Peak, SSB, SSB + NOTCH, CW, and CW(2). These options provide flexibility for audio processing needs, catering to casual listeners and serious hobbyists. The intuitive design ensures that users can quickly adapt the filter settings to optimize their audio output, improving clarity and reducing unwanted noise.

Regarding connectivity, the FL-3 is well-equipped with a headphone jack located on the front. The back panel includes three phono sockets for Input, Tape Output, and Speaker output, delivering 2.5 Watts into an 8-ohm load. Additionally, it features a 3.5mm socket for a power connector, accommodating a voltage range of 8 to 20V DC. This combination of features makes the Datong FL-3 a valuable tool for anyone looking to enhance their audio signal processing capabilities.

Used items may exhibit minor imperfections such as scratches, dents, or discolouration, which are common due to previous usage.