Low Noise Amplifier

A Low noise amplifier (or LNA) is a special amplifier that is designed to be the first amplifier in a receiver. It is vital that the first amplifier of a receiver has low noise, because the noise of the whole system is dominated by the first amplifier. This product is based on the excellent Sky67015 LNA from Skyworks. It amplifies the input signal by about 18dB while only adding 0.8dB to the noise floor!

My Motivation for designing it

I've done work with receiving weather satellites using the "Automatic Picture Taking" mode, or APT. I've written about it on my blog here. My system is severely limited by the noise figure on the front end of my software defined radios. I experimented with simple transistor amplifiers, but their performance was really no better than before. I looked around online for better solutions and came across this one. The Sky65017 is a somewhat difficult chip to find, but I was able to get some. I had the board made at DirtyPCBs and cut a solder paste stencil. I made a video about that on my youtube channel. Another great example of a case where a LNA would have helped is in my work with SDRs and VORs.

Basically, I made this product for me, but I like it so much (and I made a bunch of them) that I thought I'd share!

Good value for money

I like this design because it's a really good value for money. I looked at Minicircuits LNAs, but they're $90 minimum! I wasn't about to drop almost a hundred dollars on an amplifier that's just going to sit in the barn. With this design, you can get performance that's spitting distance to the Minicircuits product (but not in a case) for 1/3 of the cost!

That's great, but I want to try to make my own!

That's OK too. This is licensed under the TAPR open hardware license, and the PCBs are available through the DirtyPCB online store: http://dirtypcbs.com/view.php?share=4714&accesskey=279e5994140a46a48c8ed22ce1e4cca9 (this isn't a link because Tindie mangles the ampersand in the URL) the bill of materials is linked on the sidebar of this page.