[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[linrad] IM2 in RXHFA
The first production RXHFA unit has arrived here (much later than
When checking it I found I have made a mistake in the layout of the
input switches that are used to select the appropriate band pass
filter for the desired frequency band.
These switches use J310 and as it turns out stray capacitances
from gate to ground degrade IP2 seriously. This problem is
corrected by mounting the gate resistors in the air close to
the transistors rather than on the PCB.
For details, look here:
Leif / SM5BSZ