1000 X-Band Single Band PLL LNBAUTO REF: Automatically switches to Internal PLL in the absence of an EXT REF 10MHz signal Norsats Low Noise Blocks (LNBs) provide signal reception for satellite communications around the world. We offer premium performance and reliability in the smallest form factor possible. All of our standard X Band LNBs are backed by a 3 year warranty and nearly forty years of experience as the industrys leading provider of high performance LNBs.