Re: Some calculations about GAIN, LNA, ATTENUATORS, COAX...
Ruben Navarro Huedo (EA5BZ)
This evening i was playing and doing some tests.
I have around the same SNR with and without my LNA+HPF+SAW BPF ( https://store.uputronics.com/index.php?route=product/product&path=59&product_id=94 )
This is how i did the test:
I used my VNA connected to a little whip-antenna to generate an ON-AIR reference signal of 137.5 Mhz.
With my Airspy connected to my turnstile i played with gain to have the best SNR.
Then i did the same without the VNA and SNR were around the same.
Whit this test result i think the best is NOT use LNA.
What do you think?
Thank's again :-)