I have the wonderful misfortune of living a few KM from the Sky Tower in Auckland, which is a very tall, high power FM broadcast transmitter, amongst many other things.
This filter helps no end with the massive FM overload I get and therefore has a permanent home on each of my SDRs. I have also used it on a HT with less than favourable filtering/selectivity (RX only, i’m sure you can guess which) to help with the same problem.
The circuit boards were exactly as described and of excellent quality. I was able to solder my SMT components without any difficulty. My only issue was the delivery time. I ordered on June 17 and didn't receive my order until July 1st. I highly recommend the circuit boards unless you need them in a hurry.
Just arrived, and I compared against a vanilla SPF5189Z. This is cleaner with a better noise floor with good gain. Nice compact PCB, executed cleanly with some useful features like a USB power connection and LED power indicator. The ESD protection is appreciated, too. The folks at gpio are friendly and responsive.
Great pre-amp performance with my RTL-SDR (V3) dongle. Didn't expected this much efficiency from this little LNA.
If you're from a noisy environment (like me) then I would suggest to use their FM Notch Filter. Also you may have to tweak the LNA gain from 'input controls' (I'm using GQRX) in case you're input is saturated.
Thanks a ton GPIO for shipping this on the other side of the globe. Packaging was great!
I ordered 4 products from GPIO: two different LNAs, the 315 MHz Bandpass and the FM Notch. All products work excellent. I found that using the filters before the LNA work best with the RTL-SDR dongles. Also, the seller was great to work with. I made a mistake with my shipping address, and GPIO was quickly able to help me figure out who to contact to get the package before it was sent back. I highly recommend GPIO and will definitely use them in the future.