Hi Rick,
Thank you so much again, I have check the mmic one of them U5 have some strange voltage, like 6 volts on output and 2.5 volt on the imput, MSA0786 as you know is obsolete, in a big italian supplier specilized in rf components i found a minicircuit MAR-7SM+ as exact replacement for the msa (only a noise figure is way better), if this component is good for this application, i think to change all of this amps, this chip cost only 2,30€.
