LNA from Ali Express


#1

Hi All,

Finally I get the LNA from Ali Express.
It is 64 dB model.
I connect my antenna on RFin port and RTL SDR to RFOut port.
LNA powered with 12V DC and red LED working when powered.

Unfortunately it is deep silent and waterfall in the observation window is deep blue… Even nothing, literally nothing…

I tried to swap the RFin adn RFout ports, I thought may I connect them wrong way, no change, deep blue…
Like even antenna is not connected at all…

Someone can help me out?
How can I solve this problem?

Thanks a lot,
Cheers,
Serhat SUT
TA2ANK


#2

Do you have an example waterfall? 64dB is a lot, maybe you are totally over driving the RF frontend!


#3

I think & believe you are right…
I will try to install variable attenuator in front of it…
Also I think I will need band pass filter before and after LNA…
I will write in here…

Thank you…


#4

Also check the RF gain settings on your SDR. Can you link to a sample observation you did?


#5

You can test this amplifier with a TV set. If this amplifier works, then a piece of wire (in input of LNA) will work instead of a real antenna.