Yes. My transverter still uses them. I keep thinking I should build something newer but that would probably not achieve much. I have replaced the PA module with a Qualcomm amp (which is of similar vintage. The LO is rubidium locked and on the whole it is pretyy reliable. I also use one of the X4 multipliers and and an AD FracN synth chip on 2.5xx GHz for my personal 10 GHz beacon which has been running 24/7 for at least the past 6 years. It is GPS locked and was one of my earlier forrays into Arduino land. I have changed a few of the Birkett Red-spots for NE324s and the other issue I have had is that some of the source grounding vero pins needed re-soldering as the plating on the pins seemed to cause high impedance connections leading to instability.
