Hey, way cool!. Must have been mostly a west-coast phenomenon. Being in the sticks means I see mostly products that were marketed nationwide. Gotta fiigure there were a lot of "local" products here and there around the country that were never made in large quantities.
Sure, more pics would be cool. It didn't need a transformer for the tubes' heaters, since they add up to nearly 120 Volts with four of them wired in series.
Gotta wonder how they provided power for the changeover relay. Wouldn't require more than a tiny transformer for that alone, but I'm not sure how they'd do it without one. Or how I would, for that matter.
The "KLM" meter is a humorous touch. I'm sure the folks who ran that company would be mortified to see it on a sweep-tube "CB" leen-yar. They were stritctly ham, and sorta high-end when they were in business. Makes me suspect the meters were bought at a bankruptcy or a hamfest flea market after the company was long gone.
For about ten years, meters that had the "Dentron" name on the scale were plentiful at the Dayton Hamvention flea market. The company was located in Ohio, and the parts that got liquidated when they closed kept circulating for years.
Yeah, more pics would be cool. The 3-prong line cord is a safety measure. Meant to blow the fuse if a short between the incoming line volage and the chassis occurs. You really don't want the metal cabinet live with 120 Volts AC on it.
Using only one fuse implies that you know which of the line cord's (other) two wires is the "hot" side. You really want the fuse wired into the "hot" side.
Trouble is, telling which of the flat blades on the 120-Volt outlet is "hot" and which one is "neutral" is error-prone. In real life, some outlets are wired in reverse. In this case, the UNFUSED side of your line cord COULD become the "hot" side of the 120-Volt circuit. That's the reason for suggesting a fuse in EACH of the two wires going to the line plug's flat blades. No matter which one of the (other) two wires on your line cord is the hot side, it's protected from overload with its own fuse.
Makes me wonder if it was sold with "Slow-Blow"-type fuses. Those enormous filters should draw a large surge of current when they are turned on, and fill up from empty. You can keep a normal fast-blow type from popping at turn-on by using one with a current rating larger than is really safe.
If the HV filter caps are the computer-grade type with screw terminals, they may have a four-digit date code printed on them. Typically, they'll have a three-digit number that identifies who made the cap. Pretty sure Mallory was "235". Next would come four digits, two for the year, and two for the week 01 to 52. A cap marked "235-5274" would have been made by Mallory, the last week of 1974. Different manufacturers will print this info laid out without the dash, or with just the 4-digit code alone, or with those four digits at the end of an arm-s length string of digits.
If they appear to be over 30 years old, keep an eye on the small rubber plug that serves as the safety vent. When that kind of cap breaks down, that rubber plug pops out to prevent a steam explosion. Sometimes spews a foul-smelling geyser of white fog. Any outward swelling of that vent, or brown/tan powder around it is a danger sign.
Good news is that this type filter tends to last longer than the smaller ones found in most tube equipment. Longer, like 25 years instead of 15 or so. Around 40 years, they just go bad. And around 30 years, they will soon.
73
