1.9G LNA 's problem

I have used ATF 54143 to design a LNA for 1.9 GHz.
When I test it use Agilent's Noise Meter, there is a peak in NF.

In band 1.9 - 2GHz
The Gain is within + /- 1 dB, and is correct hign 15dB
except one point, NF is very low 1.2 dB
but at that point is nearly 10dB

Does any body meet the same problem in LNA test.
Seems not self oscillating

i had the same problem with lna.

u may get osilation. (out of band), take spectrum ana full span and look for it.

if u dont have osi send me the design and i will look for the prablem, but in 90% u have osilation

good lack

There are 2 reasons
1.Input Impendance does not match.
2.power supply does not connect capacitance.

i had the same problem with lna.

u may get osilation. (out of band), take spectrum ana full span and look for it.

if u dont have osi send me the design and i will look for the prablem, but in 90% u have osilation

good lack