It is a HP 691A, 692A, 693A or 694A Microwave Sweep oscillator with the -01 option. It is from the mid '60s. A manual is online, for this series. They use a Back Wave Oscillator as the RF source.
Frequency Ranges:
691A: 1 to 2 GHz
692A: 2 to 4 GHz
693A: 4 to 8 GHz
694A: 8 to 12.4GHz
The -01 option - Sweep Oscillators are equipped internally to provide automatically leveled RF output, and are distinguishable from standard Sweep Oscillator by the label INT ALC on the pushbutton under the POWER LEVEL control.
Option 01 Oscillators have precision type N RF output connectors which are intended for use with standard type N connectors (e.g., UG-21 D/U) only. CAUTION: DO NOT COUPLE TWO PRECISION CONNECTORS. The male connector center conductor has larger diameter than the center conductor receptacle in the female connector. Consequently, coupling precision connectors can cause severe connector damage.
For those who do not know. This site is sandwiched between two neighborhoods. It is not surprising that teenagers went in over the years and destroyed parts of it. I still recall the gargantuan structure. It's a shame that it could not be converted into some kind of learning center. I was told that there were many vials of mercury left behind after the demolition.
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Wow, brings back memories. i worked on equipment just like that when I was in SatCom in the 1980's. The Az/El control looked just like what we had on our system. I was stationed in Augsburg Germany in the late 1980's and there was an old Nazi base there that was plowed over but I found an underground access tunnel that I could not get into. It is probably still there but the entrance area was bull dozed. It used to be an airstrip in WW2 and was where Hess flew out of when he negotiated the 'surrender' of Germany.
I grew up in the neighborhood that now surrounds that property. It was common for myself and other kids to climb the dish regularly. It was pretty amazing as a kid, somewhat movie-like. We explored through all the buildings....at the time we weren't aware that was trespassing (being kids). They tore down the dish a few years ago. I would love to have more information about the abandon baseball field randomly placed next to the property if this site could look into that....
Frequency Ranges:
691A: 1 to 2 GHz
692A: 2 to 4 GHz
693A: 4 to 8 GHz
694A: 8 to 12.4GHz
The -01 option - Sweep Oscillators are equipped internally to provide automatically leveled RF output, and are distinguishable from standard Sweep Oscillator by the label INT ALC on the pushbutton under the POWER LEVEL control.
Option 01 Oscillators have precision type N RF output connectors which are intended for use with standard type N connectors (e.g., UG-21 D/U) only. CAUTION: DO NOT COUPLE TWO PRECISION CONNECTORS. The male connector center conductor has larger diameter than the center conductor receptacle in the female connector. Consequently, coupling precision connectors can cause severe connector damage.