Which Final FET Fails?
My low band QDX has just failed for the fourth time. ?Each time only Q9 has failed (shorted D-S). ?No other parts have been replaced. ??
My high band QDX also failed once, also Q9. ??
Both are built as 9 volt version, power is via a linear LM317 regulator with 1 amp current limiting.
Any ideas why this one part is more stressed than others?
I have just added 1N4148 diodes as in the QMX schematic.?
