Uputronics filtered preamps for improved  reception on 137.5MHz.

New Unit for 2024 now with USB-C and Power LED.

Buy direct from us or via one of our resellers here:


This is a cost effective SAW based unit which give excellent performance gains.

All our preamps are compatible with most USB SDR Dongles such as the RTL USB, Airspy, Fun Cube. You can power them from either bias tee (This item is 100% compatible with the Airspy bias-tee) or a simple USB-C cable (Not Supplied - See related items for a suitable USB Type A to C Cable).

Bias-tee voltage input is 5V. Note: Unlike previous models, component supply issues mean bias-tee input voltage is 5V max. 

This unit is a small filter and preamp designed to go between a software defined radio receiver and an antenna. 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. This particular model is tuned for use with 137.5MHz. To block strong commercial FM signals a high pass filter is installed before the LNA.

The LNA used is a MiniCircuits PSA4-5043+ which provides at least 21dB of gain @ 137.5MHz. To stop out of band intermodulation an 137.5MHz SAW bandpass filter, which has a 7.6MHz bandwidth is also present. The insertion loss of this filter is approximately 1.4dB.  Connectors are SMA female both sides.

Since March 2020 we have fitted improved SMA female connectors for antenna input and radio output to address the issue of the SMA barrels coming away. Also the Bias Tee regulator kit is now fitted as standard

See related items for a suitable USB Type A to Mini B Cable to power the unit.

Documentation

Uputronics FPA Series Preamplifiers Datasheet

Mechanical Diagram showing optional Lug Kit
CE Certificate of Conformity
UKCA Certificate of Conformity

137.5MHz NOAA/APT Filtered Preamp

  • Brand: Uputronics
  • Product Code: HAB-FPA1375
  • Availability: 499
  • £59.99

  • Ex Tax: £49.99

Available Options


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Tags: 137.5MHz Filtered Preamp