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Originally Posted by old_tv_nut
Just out of curiosity, what kind of color bar generator makes those annotated bars?
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I kinda wondered if someone might notice that.
It's a B&K Television Analyst. It has a flying-spot scanner consisting of a small CRT (which glows with a odd-looking dim purple-ish light... its output isn't UV or something is it..?) with a phototube sensor set a few inches away. There's a holder mounted in front of the CRT for inserting tranparancies. The phototube sensor measures light from the CRT as the CRT scans a plain raster, thus generating a video signal based on whatever image is on the transparancy. These things originally came with several different transparancies, including various dot/line patterns and a version of the ever-popular "Indian Head" test pattern. While this sort of flying-spot scanner is only capable of producing B&W images (I'm not sure it can even make grey-scale images; I haven't tried that yet), most? all? TV Analysts have a built-in simple ungated rainbow generator, which if enabled and used with the appropriate "color bar" slide, makes for something that looks like a gated rainbow with nifty labels for the colors.
Oh, and it also has a simple audio oscillator to provide a test tone on the sound carrier.
I've seen these TV Analysts show up at hamfests for years (usually at near-giveaway prices), but for whatever reason never bothered to pick one up until a couple of weeks ago. I wish I had earlier-- I never quite realized just how versitile it is! Not only can it generate arbitrary patterns on its scanner, but it can output them in a variety of ways-- either use its built-in modulator to produce RF (at any VHF channel-- later versions of the Analyst could even output on any UHF channel as well) or produce directly at IF frequencies (tunable over a wide range too!), or a plain detector-level video signal. It can even be used to provide substitute sync signals to a TV, or vertical and/or horizontal sweep signals. The video sweep rates are even adjustable over what appears to be a fairly wide range. I'm not sure (I don't have the manual, unfortunately), but I suspect it can even directly produce a substitute HV sweep (from an 'extra' horizontal output tube inside the Analyst) to a TV for troubleshooting purposes.
There appear to be a variety of other things this puppy can do, but without the manual, I'm not quite sure what they are.