Retrotechtacular: How Television Worked In The 1950s

Watching television today is a very different experience from that which our parents would have had at our age, where we have high-definition digital on-demand streaming services they had a small number of analogue channels serving linear scheduled broadcasting. A particular film coming on TV could be a major event that it was not uncommon for most of the population to have shared, and such simple things as a coffee advert could become part of our common cultural experience. Behind it all was a minor miracle of synchronised analogue technology taking the signal from studio to living room, and this is the subject of a 1952 Coronet film, Television: How It Works!  Sit back and enjoy a trip into a much simpler world in the video below the break.

Filming a TV advert: 1950s housewife sells cooker
Production values for adverts had yet to reach their zenith in the 1950s.

After an introduction showing the cultural impact of TV in early-50s America there’s a basic intro to a cathode-ray tube, followed by something that may be less familiar to many readers, the Image Orthicon camera tube that formed the basis of most TV signals of that era.

It’s written for the general public, so the scanning raster of a TV image is introduced through the back-and-forth of reading a book, and then translated into how the raster is painted on the screen with the deflection coils and the electron gun. It’s not overly simplified though, for it talks about how the picture is interlaced and shows how a synchronisation pulse is introduced to keep all parts of the system working together.

A particularly fascinating glimpse comes in a brief mention of the solid copper co-axial cable and overland microwave links used to transmit TV signals across country, these concrete towers can still be seen today but they no longer have the colossal horn antennas we can see in the film.

A rather obvious omission in this film is the lack of any mention of colour TV, as while it would be late 1953 before the NTSC standard was formally adopted and early 1954 before the first few colour sets would go on sale. Colour TV would have been very much the Next Big Thing in 1952, but with no transmissions to watch and a bitter standards war still raging between the field-sequential CBS system and RCA’s compatible dot-sequential system that would eventually evolve into the NTSC standard  it’s not surprising that colour TV was beyond the consumer audience of the time.

Thus we’re being introduced to the 525-line standard which many think of as NTSC video, but without the NTSC compatible colour system that most of us will be familiar with. The 525-line analogue standard might have disappeared from our living rooms some time ago, but as the last few stations only came off-air last year we’d say it had a pretty good run.

We like analogue TV a lot here at Hackaday, and this certainly isn’t the first time we’ve gone all 525-line. Meanwhile for a really deep dive into the inner workings of TV signal timing, get ready to know your video waveform.

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Designing For The Small Grey Screen

With the huge popularity of retrocomputing and of cyberdecks, we have seen a variety of projects that use a modern computer such as a Raspberry Pi bathed in the glorious glow of a CRT being used as a monitor. The right aesthetic is easily achieved this way, but there’s more to using a CRT display than simply thinking about its resolution. Particularly a black-and-white CRT or a vintage TV has some limitations due to its operation, that call for attention to the design of what is displayed upon it. [Jordan “Ploogle” Carroll] has taken a look at this subject, using a 1975 Zenith portable TV as an example.

The first difference between a flat panel and a CRT is that except in a few cases it has a curved surface and corners, and the edges of the scanned area protrude outside the edges of the screen. Thus the usable display area is less than the total display area, meaning that the action has to be concentrated away from the edges. Then there is the effect of a monochrome display on colour choice, in other words the luminance contrast between adjacent colours must be considered alongside the colour contrast. And finally there’s the restricted bandwidth of a CRT display, particularly when it fed via an RF antenna socket, which affects how much detail it can reasonably convey. The examples used are games, and it’s noticeable how Nintendo’s design language works well with this display. We can’t imagine Nintendo games being tested on black-and-white TV sets in 2022, so perhaps this is indicative of attention paid to design for accessibility.

While they require a bit of respect due to the presence of dangerous voltages, there’s a lot of fun to be had bringing a CRT into 2022. Get one while you still can, and maybe you could have a go at a retro cyberdeck.

Can You Help Solve The Mystery Of This 1930s TV?

84 years ago, a teenager built a TV set in a basement in Hammond, Indiana. The teen was a radio amateur, [John Anderson W9YEI], and since it was the late 1930s the set was a unique build — one of very few in existence built to catch one of the first experimental TV transmitters on air at the time, W9XZV in Chicago. We know about it because of its mention in a 1973 talk radio show, and because that gave a tantalizing description it’s caught the interest of [Bill Meara, N2CQR]. He’s tracking down whatever details he can find through a series of blog posts, and though he’s found a lot of fascinating stuff about early TV sets he’s making a plea for more. Any TV set in the late ’30s was worthy of note, so is there anyone else out there who has a story about this one?

The set itself was described as an aluminium chassis with a tiny 1″ CRT, something which for a 1930s experimenter would have been an expensive and exotic part. He’s found details of a contemporary set published in a magazine, and looking at its circuit diagram we were immediately struck by how relatively simple the circuit of an electrostatically-deflected TV is. Its tuned radio frequency (TRF) radio front end is definitely archaic, but something that probably made some sense in 1939 when there was only a single channel to be received. We hope that [Bill] manages to turn up more information.

We’ve covered some early TV work here not so long ago, but if you fancy a go yourself it’s not yet too late to join the party.

Retrotechtacular: A DIY Television For Very Early Adopters

By our very nature, hackers tend to get on the bandwagon of new technology pretty quickly. When something gee-whiz comes along, it’s folks like us who try it out, even if that means climbing steep learning curves or putting together odd bits of technology rather than waiting for the slicker products that will come out if the new thing takes off. But building your own television receiver in 1933 was probably pushing the envelope for even the earliest of adopters.

“Cathode Ray Television,” reprinted by the Antique Valve Museum in all its Web 1.0 glory, originally appeared in the May 27, 1933 edition of Popular Wireless magazine, and was authored by one K D Rogers of that august publication’s Research Department. They apparently took things quite seriously over there at the time, at least judging by the white lab coats and smoking materials; nothing said serious research in the 1930s quite like a pipe. The flowery language and endless superlatives that abound in the text are a giveaway, too; it’s hard to read without affecting a mental British accent, or at least your best attempt at a Transatlantic accent.

In any event, the article does a good job showing just what was involved in building a “vision radio receiver” and its supporting circuitry back in the day. K D Rogers goes into great detail explaining how an “oscillograph” CRT can be employed to display moving pictures, and how his proposed electronic system is vastly superior to the mechanical scanning systems that were being toyed with at the time. The build itself, vacuum tube-based though it was, went through the same sort of breadboarding process we still use today, progressing to a finished product in a nice wood cabinet, the plans for which are included.

It must have been quite a thrill for electronics experimenters back then to be working on something like television at a time when radio was only just getting to full market penetration. It’s a bit of a puzzle what these tinkerers would have tuned into with their DIY sets, though — the airwaves weren’t exactly overflowing with TV broadcasts in 1933. But still, someone had to go first, and so we tip our hats to the early adopters who figured things out for the rest of us.

Thanks to [BT] for the tip.

 

Satellite Snoopers Pick Up Surprising TV Broadcast

While Internet based streaming services appear to be the future of television, there are still plenty of places where it comes into the home via a cable, satellite, or antenna connection. For most satellite transmissions this now means a digital multiplex carrying a host of channels from a geostationary satellite, for which a set-top box or other decoder is required. Imagine the surprise of satellite-watchers than when the Russian polar communications satellite Meridian 9 which has a highly elliptical orbit was seen transmitting old-style terrestrial analogue TV (ThreadReader Link). What on earth was happening?

How a Russian polar comms satellite picked up a TV station.
How a Russian polar comms satellite picked up a TV station.

The TV signal in question comes from Turkmenistan, so were some homesick Turkmenistanis in an Antarctic base being treated to a taste of their country? The truth is far more interesting than that, because the signal in question comes from a terrestrial transmitter serving domestic TV viewers in Turkmenistan.

We’ve all heard of the idea that somehow every TV show ever transmitted is somewhere out there still traveling as radio waves across space, and while perhaps we can’t fly far enough out to check for 1960s Doctor Who episodes it’s true that the horizontal transmissions from a TV tower pass out into space as the earth curves away from them.

Thus Meridian 9 passed through the beam from the Turkmenistan transmitter which happened to be on a UHF frequency that matched one of its transponders, and the result was an unexpected bit of satellite TV. We’re indebted to the work of [@dereksgc] and [Scott Tilley] for bringing us this fascinating observation. We’ve featured [Scott]’s work before, most notably when he relocated a lost NASA craft.

Retrotechtacular: Measuring TV Audiences With The “Poll-O-Meter”

It may come as a shock to some, but TV used to be a big deal — a very big deal. Sitting down in front of the glowing tube for an evening’s entertainment was pretty much all one had to do after work, and while taking in this content was perhaps not that great for us, it was a goldmine for anyone with the ability to monetize it. And monetize it they did, “they” being the advertisers and marketers who saw the potential of the new medium as it ramped up in early 1950s America.

They faced a bit of a problem, though: proving to their customers exactly how many people they were reaching with their ads. The 1956 film below shows one attempt to answer that question with technology, rather than guesswork. The film features the “Poll-O-Meter System,” a mobile electronic tuning recorder built by the Calbest Electronics Company. Not a lot of technical detail is offered in the film, which appears aimed more at the advertising types, but from a shot of the Poll-O-Meter front panel (at 4:12) and a look at its comically outsized rooftop antenna (12:27), it seems safe to assume that it worked by receiving emissions from the TV set’s local oscillator, which would leak a signal from the TV antenna — perhaps similar to the approach used by the UK’s TV locator vans.

The Poll-O-Meter seems to have supported seven channels; even though there were twelve channels back in the day, licenses were rarely granted for stations on adjacent channels in a given market, so getting a hit on the “2-3” channel would have to be considered in the context of the local market. The Poll-O-Meter had a charming, homebrew look to it, right down to the hand-painted logos and panel lettering. Each channel had an electromechanical totalizing counter, plus a patch panel that looks like it could be used to connect different counters to different channels. There even appears to be a way to subtract counts from a channel, although why that would be necessary is unclear. The whole thing lived in the back of a 1954 VW van, and was driven around neighborhoods turning heads and gathering data about what channels were being watched “without enlisting aid or cooperation of … users.” Or, you know, their consent.

It was a different time, though, which is abundantly clear from watching this film, as well as the bonus ad for Westinghouse TVs at the end. The Poll-O-Meter seems a little silly now, but don’t judge 1956 too hard — after all, our world is regularly prowled by equally intrusive and consent-free Google Street View cars. Still, it’s an interesting glimpse into how one outfit tried to hang a price tag on the eyeballs that were silently taking in the “Vast Wasteland.”

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CRT cyberdeck

Old Portable TV Becomes Unique CRT Cyberdeck

Remember the “suitcase” form-factor for PCs? In the time before latops, these luggable machines were just the thing for the on-the-go executive. OK, maybe not really — but the ability to have PC, monitor, and peripherals in a single package had real appeal, and a lot of that rationale is behind the cyberdeck phenomenon. So when we saw this retro portable TV turned into a cyberdeck, it really caught our eye.

Ironically, the portable black-and-white TV that [Lucas Dul] chose as the basis for his cyberdeck hails from about the same period in time that luggable PCs were having their brief time in the sun. Scored from eBay, the Magnavox TV/radio combo had seen better days, and required a bit of surgery to repair what might have been drop damage. With the CRT restored and the video and audio paths located, the TV got a Raspberry Pi, a small touchpad, and a couple of concealed USB connectors. The Pi’s composite output drives the CRT, with about the results you’d expect. The keyboard appears to be just about the right size to serve as a cover, but [Lucas] said that’s a future project.

Still, with the TV’s original handle acting as a stand, this cyberdeck gives off a real Compaq or IBM portable PC vibe. We’ve seen a few luggable-lookalike cyberdecks before, but none that dared use a CRT monitor. It may be a far cry from HDMI, but we really appreciate that [Lucas] chose this way rather than slapping in an LCD.

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