And just like that, my 1980 vintage HP 3335A Synthesizer died this afternoon when I turned it on to get a better graph of my K3s PLL frequency hunting. Dreaded “Unlocked” indicator and crazy display. I have another that I’ve already cannibalized for parts, so there is some chance I can repair the one that was working. But this also gives me an excuse to check out my Siglent SDG-2042X, which sports a 10 MHz external reference. It all depends on how they implemented their PLL if it will be useful at the sub millihertz level like the HP was. If the Siglent works, then I will pull the HP Oven controlled Reference out of both and eBay them.
Good timing, however, as I was able to use the HP to verify that everything was all set correctly prior to the FMT. I will miss the old fella.
