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Old October 11th 06, 08:13 PM posted to rec.radio.amateur.homebrew
[email protected] Lathi.Tan@gmail.com is offline
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First recorded activity by RadioBanter: Oct 2006
Posts: 10
Default effect of cascading LNAs

I asked what I don't know. I am expecting a helpful answer.

The frequency is 70MHz.


Wes Stewart wrote:
On 11 Oct 2006 11:38:03 -0700, wrote:

What do you mean by overload? How come there is too much garbage as
long as my NF is low?

I actually need 143dB gain. What kind of problem I will have if I just
use 6 stages of amplifiers, like 1stage(20dB, NF2.4dB) 2nd stage(30dB,
NF3db), 3rd stage(43dB, NF 6.2dB), 4th stage(43dB NF6.2dB). It seems my
NFtotal is pretty low. What's my problem?


Your problem is you don't know what you're doing.

What frequency is this oscillator going to run at?