5784-3

5784-3

The 5784-3 is a single band tunable bandpass filter from Netcom’s TunePro 2W series. It covers 960 MHz to 1240 MHz and tunes in 1 MHz steps in 10 microseconds.

The filter gives you the control you would expect from a much larger part, in a package of only 0.575 x 0.575 x 0.175 inches (14.605 x 14.605 x 4.4 mm). It handles 2 watts, runs from a single 3.3 VDC supply drawing no more than 30 mA, and is tuned over a simple SPI serial link.

The 960 to 1240 MHz range is the busiest part of L-band. DME and TACAN navigation beacons send high power pulses across 960 to 1215 MHz, Link 16 terminals hop across almost the whole band at a few hundred watts, IFF and secondary radar transponders transmit at 1030 and 1090 MHz, and long range surveillance radar sits just above 1215 MHz. A receiver working here has to cope with all of that while listening for something far weaker.

That is the job of the 5784-3. Placed in front of the low noise amplifier, this tunable bandpass filter passes only the slice you are tuned to, roughly 30 MHz wide, and keeps the rest of the band out. Strong transmitters nearby can then no longer compress the amplifier or use up the dynamic range of the converter. Because it retunes in 1 MHz steps in 10 microseconds, one part does the work of a whole bank of switched filters, in a footprint of 0.575 inches square. Typical uses are receiver front end preselection, ADS-B and IFF equipment, co-site protection on crowded airframes, electronic warfare and spectrum monitoring receivers, radar warning receivers, and software defined radio.