This device is a shortwave tunable band-pass filter center frequency receiver amplifier, covering a frequency range of 3-30MHz, with adjustable gain from 0-30dB.
The signal from the ANT interface is filtered through the built-in shortwave tunable narrowband filter, amplified by a low-noise amplifier, and then delivered to the RX/TX interface.
The tunable narrowband filter has a bandwidth of about 1MHz. By adjusting the filter knob to the target frequency, the signal at the target frequency passes through while other frequencies on both sides are attenuated. The filtered signal is then amplified by the low-noise amplifier. The amplifier gain is adjustable and should be set appropriately according to the received signal strength and the device’s dynamic range to prevent receiver overload.
A built-in relay allows transmission while the device is off or when the PTT signal line is connected. The maximum withstand voltage is AC 440V and DC 120V, and the maximum withstand current is 8A. Please use it below the maximum voltage and current ratings.
All rear interfaces are BNC female connectors. The RX/TX labeled connector should be connected to a transceiver or other receiving/transmitting equipment or receiver, while the ANT labeled connector should be connected to an antenna.
For transceiver use, please turn off the amplifier before transmitting or connect the PTT signal line to the amplifier to control the internal relay switch.
The PTT interface is a 3.5mm mono audio female connector.
Prepare a 12V or 13.8V linear regulated DC power supply. The power plug should be 5.5×2.1, center positive, outer negative, and inserted into the black DC socket on the back of the amplifier. Ensure the voltage is normal and the polarity is correct.
Power on by pressing the black button on the right side of the front panel; the green light will turn on. When connected to PTT and transmitting, the red light will illuminate.
The TUNE knob is for overall adjustment of the filter’s center frequency and can adjust the filter from 3MHz to 30MHz.
FINE TUNE is for fine-tuning specific frequencies.