Klystron Refresher 101
Just some interesting pix to show why TV engineers got such a kick out of Argonne National Labs.
More similarities than you'd think.

Click on the images to see larger versions.
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Waveguide and high power transmission line being assembled. It was all put together just above the transmitter cabinets and then slowly elevated as one piece to the ceiling.
Waveguide being assembled. A bizillion bolts.
Waveguide combiner. A little smaller than the Argonne guides. Mostly because our frequency is so much higher - 760mhz as opposed to 300+mhz. As frequency goes up, wavelenght goes down. From left you can see waveguide coming in from two visual power klystrons. They meet and combine and continue to the right. Upper horizontal waveguide is the combined visual klystrons and combined aural klystron power on its way to the tower and antenna.
Front of transmitter. L to R - Visual klystron cabinet #1, Visual klystron cabinet #2, Aural klystron cabinet, HV control and switching.
Waveguide visible at ceiling level.
Bad day at Black Rock!!
Catastrophic meltdown. The tube arced and the protection didn't catch it. Two or three seconds of full power into a tube whose beam had collapsed. The smaller hoses visible at the rear bottom are for magnet and body cooling water. The high volume hoses at the lower right side (hard to see) are the final anode cooling water. RF output coupler is lower left - making the 90 degree upward bend. Melted cathode is at the top of the magnet assembly. Three seconds - $60,000 out the window.
Close up of melted cathode (our tubes are inverted so the anode is at cabinet ground). The melted goo is ceramic and silicone (They are very hard to melt - but give them enough energy and...)
Different view.
Closeup of melted ceramic and silicone goo. Some escaped berillium from the cathode makes this an EPA issue. Very toxic. Had to prove we contained it all.
Top view of melted cathode.
Side shot showing klystron in the magnet assembly. Assembly takes an hour or so to remove from the transmitter.
Destroyed klystron being raised by winch out of the magnet assembly.
Nearly raised out of the assembly. Visible at the bottom right of the tube is the 60kw output connector.
Full view of the destroyed klystron. Just below the top is the 1/2" semi-flex input coax. You can see the black hoses that carry cavity cooling water leap-frogging from one cavity to the next. These are 4 cavity tubes. Each one tunes the final bandwidth and makes the tube wideband enough to amplify the entire visual carrier that is 6Mhz wide. The bottom red housing is the high-pressure water cooled anode where the electron plasma beam smashes to a full stop from nearly the speed of light. The cavity just above is where the high energy beam resonates out the amplified RF. Normally, they're much cleaner that this!
Same view - back side.
Burned klystron being lowered into the anode protective box in preparation for shipping crate to go back to Varian (same folks who made the Argone klystrons).
Empty magnet assembly before cleanup and refurbishing. Note the coil rings. Each one has an embedded water line for cooling.
View down the magnet assembly. The rods are the guide posts for the klystron. You can see the high-pressure water connections for the anode at the bottom.
Magnets on - full field test! Drill bit and screwdriver balanced on my finger. I'm not giving the finger - it's just my longest one!
Magnets on - full field test! Drill bit, screwdriver and eight screws balanced on my finger. Note that I was smart enough to remove my watch!
Magnets on - full field test! From the top, 9 screws, a drill bit, and a screwdriver hang from another screwdriver - showing the exact magnetic center. This is where the electron plasma beam forms in the middle of the klystron.
New klystron being lowered into the magnet assembly. This was two nights later after the damage and destruction had been cleaned, blasted wires replaced, cavities tuned, goo cleaned up and berillium disposed of.
New klystron being lowered into the magnet assembly.
New klystron being lowered into the magnet assembly.
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