I am trying to cascade two low noise amplifiers in series, is that not possible? As i do not get a signal on the output. E.g. two of https://www.minicircuits.com/WebStore/dashboard.html?model=ZX60-112LN+ in series. I am not overloading the input as the signal is -80 dbm input.

 

I am trying to cascade two low noise amplifiers in series, is that not possible? As i do not get a signal on the output. E.g. two of https://www.minicircuits.com/WebStore/dashboard.html?model=ZX60-112LN+ in series. I am not overloading the input as the signal is -80 dbm input.

What is your input source?
What power source did you use?

 

antenna rf 1Ghz, it works with 1 LNA however with two in series it does not.

 

So both of the LNAs are powered and the output of one is not overloading the second one. How do you know this?
What is the antenna/feedline impedance?
Output power of the first LNA is 14.5 to 16.5 dBm and you're trying for another 27 dB of gain?

 

yes i am trying to get more gain, how is the output 14.5dbm for first LNA. with a -80 db input signal and 27 db gain, wouldnt the output be -53dbm? Everything is impedance matched 50 ohms. On the datasheet it says the maximum input is ( Input RF Power (no damage) +20 dBm ) so -53dbm is much lower. Unless i am interpreting something incorrectly.

 

yes i am trying to get more gain, how is the output 14.5dbm for first LNA. with a -80 db input signal and 27 db gain, wouldnt the output be -53dbm? Everything is impedance matched 50 ohms. On the datasheet it says the maximum input is ( Input RF Power (no damage) +20 dBm ) so -53dbm is much lower. Unless i am interpreting something incorrectly.

I'm just going by the numbers in the datasheet. Tell me, if you interchange the positions of the two devices in series do you get the same result? That is the going antenna to output works and the second one does not?

 

A general note,
in case you have not used these thigns before

a) they are extremely static sensitive
b) they are extremely sensitive to having an input with no power applied
c) the input power is defined as the max, not the RMS average,
d) check any DC bias between stages, I don't know these ones, but they might need to be AC coupled