Sharp BS1K1EL100A PLL LNB Review

The Sharp BS1K1EL100A is a special LNB. Like all universal LNB's, this LNB receives the 10.7-11.7Ghz and 11.7-12.75Ghz Ku bands and looks like a normal single output universal LNB. But inside it hides two characteristics that make this LNB "special". For one thing, this is a PLL LNB. PLL LNB's, as I explained in my previous post, have much higher frequency stability than the more common DRO LNB's. This makes them specially suited to receive low symbol rate transponders. Marketing claims this LNB has an NF of 0.4 dB, 58 dB gain, 25 dB of cross polar discrimination and current consumption between 80-120mA.

To my knowledge this was the first mass market LNB with PLL technology. According to Sharp this is the first LNB in the world with a unique SoC (System on Chip) that integrates in a single IC the mixer, IF, amplification, PLL and LO. Also according to Sharp, this technology allows decreasing the Noise Figure and increasing the Gain linearity. The two local oscillator frequencies needed to receive the full Ku band are generated from a 25Mhz crystal. Inside the IC this 25Mhz frequency is multiplied by 390 (for 9.75Ghz low band) and 424 (for 10.6Ghz high band).

Teardown

This LNB is easy to open. As you can see, it's really small and short. It may be difficult to adjust signal focus on some dishes.

But another difference separates this LNB from the rest. This is due to its unique waveguide geometry. To my knowledge this is also the first universal LNB to use a square waveguide. Until this model came along all universal LNB's have been using a circular waveguide.

Inside the LNB we don't find the common NE3503M04 HJ-FET transistors (typical NF of 0.45dB @ 12 Ghz), but the newer NE3513M04 HJ-FET with practically identical specs. The mixer, IF amplification, PLL and LO IC is marked C520. PCB and component soldering are top quality as is usual with Sharp LNB's.

Tests

This LNB performs well, but apart from the good frequency stability it doesn't really stand out. I noted that it slightly favours reception of the mid to upper part of the Ku band. If you want to receive very weak signals on the lowest frequencies this may not be the best LNB for that purpose, but it's perfectly adequate under "normal" reception conditions. This LNB was sold very cheaply (< 5 Euros). For the price and build quality it's a good LNB.

To learn more about LNB's and PLL technology, please read my previous post on the subject: PLL vs. DRO LNB - Which is better?