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here is the schematic.
2 at41485 as amplifier
at41485 1dB point is 18dBm when ic=40mA
on this schematic's instruction,it is said the LNA's 1dBpoint is 7dBm
but when i test it with Network Analyzer
S21 is 28dB when input is -20dBm,thats right
but when input is -10dbm s21=-20dB
when input is 0dbm,the gain is as low as 9
i really which part of this schem make this happen?how it works?and why design like that?
ps :Attached Thumbnails is not right ,idont know how to delete it
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