868/915MHz Filtered Preamplifier with Transmit Bypass

This unit is a filtered preamp designed to go between a radio transceiver and an antenna which gives excellent performance gains for reception and bypasses the preamplification circuit when a transmission is detected.

Power is either via bias tee or a USB-C cable (not included).. Bias-tee voltage input is 5V.

Using a SAW bandpass filter and a low noise amplifier (LNA), it stops out-of-band intermodulation while providing additional gain for increased sensitivity. The LNA is before the SAW filter. These particular models are tuned for use with frequencies centred on 868MHz (usable 863-876MHz) or 915MHz (893MHz-935MHz). The LNA provides around 15dB of gain at 868/915MHz.

SMA female connectors are fitted for antenna input and radio output, a blue power indicator is provided which switches to red to indicate the unit is in bypass mode.

Max TX power +15dBm (30mW). TX detection threshold -5dBm (+/-2dBm). Originally designed to support a demand within the Helium cryptomining scene.

Don’t need the transmit bypass? Check out the standard 868MHz pre-amplifier here.

Resources

• Datasheet
• Mechanical Diagram (showing lug kit which is not included and not yet stocked – let us know if you would like us to stock the lugs!)