The MFJ-1040C is designed to enhance your ability to copy weak signals by rejecting out-of-band signals and images. Covering a wide frequency range from 1.8 to 54 MHz, this device offers up to 20 dB gain with adjustable gain control. Utilizing a cascode FET/bipolar transistor configuration, it ensures low noise and high gain performance. Additionally, it features a 20 dB attenuator and the capability to connect 2 antennas and 2 receivers using SO-239 connectors. The unit also includes an automatic bypass for transmitting up to 125 Watts, along with a jack for push-to-talk functionality. Power options include 9-18 VDC or the MFJ-1312D power adapter.

preselector that functions as a band-pass filter. This component effectively blocks unwanted frequencies that are out-of-tune from passing through the antenna to the radio receiver or preamplifier. By preventing these troublesome frequencies from reaching the connected devices, the preselector helps to maintain signal clarity and reduce interference. This feature is crucial in optimizing the performance of the radio receiver by ensuring that only the desired signals are received, enhancing overall signal quality and reception capabilities.

In summary, the MFJ-1040C is a versatile tool for radio enthusiasts seeking to improve their signal reception capabilities. With its advanced features such as out-of-band signal rejection, adjustable gain control, and dual antenna/receiver connectivity, this device offers a comprehensive solution for enhancing weak signal copying. The inclusion of a band-pass filter preselector further enhances its performance by effectively blocking unwanted frequencies, ensuring optimal signal quality and reducing interference for a superior listening experience.