Sierra Philco 470a-500 Power Signal Source

[macona]

I picked up this Sierra 470A-500 power signal source. It seems to work, I guess, to at least outputs RF and I checked with an external meter and load. It isn't quite what I was expecting inside. The knob moved something in a tuned cavity, I really dont know much about this old tech. Output is coupled on the side of the cavity and there is a knob that moves it in and out. The thing is 5 to 500mhz and up to 80W out. The scale on the wheel skips a range between roughly 50mhz and somewhere in the low hundreds. The thing is there is nothing to switch between these two scales. I really have no idea what is going on with this. I can only find a couple others on the internet and no manuals whatsoever.

Anyone mess with one of these? I got it thinking it might be be usable for an inductively couple plasma cleaner. Paid $30 for it so no great loss.

IMG_5875 by Jerry Biehler, on Flickr

IMG_5874 by Jerry Biehler, on Flickr

IMG_5872 by Jerry Biehler, on Flickr