Handcrafted Scope Clocks with circle graphics
The Oscilloclock Lab isn’t bustling again just yet, but we’re getting things prepared!
Return visitors to Oscilloclock.com will notice a big change from last week – the site is now blindingly fast!
We’ve upgraded hosting infrastructure and achieved massive improvements in response and load times.
So: Browse. Search. Learn. Enjoy our cathode-ray tube escapades. And subscribe on the main page to stay tuned!
In the last post, we took a look at a funky new sidereal clock from the Oscilloclock Lab. Now let’s take a look at what fanciness went into it!
[Alan], our astronomer protagonist, wanted to install all the electronics inside his Tektronix 620 X-Y Monitor. He didn’t need a nice fancy case.
No problem! We supplied the Oscilloclock Bare – our stand-alone controller board that generates images and text rendered in smooth and silky Lissajous figures.
The board ships on a cast acrylic mount to make it easy to test externally, prior to installation into the host piece of equipment.
Next, we added the Oscilloclock Wave. This is a Wi-Fi adapter that allows an Oscilloclock to pull (Solar) time from NTP servers over the internet, keeping accurate time indefinitely.
For [Alan], we left the cabling and aesthetics options open, and shipped the basic Wave Core module instead of the stand-alone type pictured above.
Finally, we included a decent quality power pack, to allow running the assembly prior to installation.
This would eventually be eliminated by powering the unit from the Tek 620’s internal supply itself.
To transform the Oscilloclock Bare into the astronomically great Astro Clock that it is today, we needed sidereal time.
Easy! The US Naval Observatory Astronomical Applications Department provides a publicly available API for querying sidereal time, given a location.
The Oscilloclock Wave already had features to pull earthquake data from a similar API and push it to the Oscilloclock for display. Extending this for another API wasn’t astronomically difficult.
The Wave sports a bunch of advanced settings for particularly tweak-loving oscillofans out there. We just needed to add a few more! These are to enable querying and sending sidereal time to the Oscilloclock, and to set the location.
Some readers may have guessed that formulae and code libraries for calculating sidereal time are readily available. Why didn’t we just implement the calculation in code, and avoid depending on an external API?
Well, I’ve mentioned before that the current revision Oscilloclock Control Board uses a minimal-specification microcontroller with very limited capabilities, and is heavily optimized by coding in assembly language.
Sadly, this chip was already jam-packed to the hilt, and there simply wasn’t any more space left for the code and run-time memory needed to calculate sidereal time internally.
And writing the necessary floating-point calculations in assembly would be no mean feat!
Why Assembly Code?
Because We Can.
But, it sure ain’t easy…
So NO – we couldn’t easily calculate sidereal time, and it was API Option full steam ahead!
Even with its minimalist microcontroller chip, we’ve managed to squeeze some amazing stuff into the Oscilloclock Control Board firmware.
For this build, we needed yet more screens.
First, we used our trusty Figure Creator software to render a rudimentary telescope into Circle Graphics sprite code.
We then crafted a simple Astro Clock splash screen, by adding some random circles for stars and laying out basic text around the telescope.
Finally, we added some basic digital and analog clock screens, using the same telescope figure as a centrepiece. This was mostly straightforward, but the existing clock hand drawing code did need some tweaking, to reference either solar time or sidereal time depending on the active screen.
Invoiced. Paid. Shipped. Received. Treasured forever. Right?
Wrong!
A year after [Alan] received his lovely Astro Clock, the unhappenable happened. The Astronomical Applications API was taken down!
The site was taken offline for a planned six months, for “modernization”. [Alan]’s sidereal clock was relegated to a normal solar Oscilloclock, albeit temporarily.
But as lovers of electron beams striking phosphor, we always look at the bright side! Six months is still relatively short in astronomical terms! We resignedly marked “X” on the calendar, and bided our time.
But then… the unfathomable fathomed. The COVID-19 pandemic struck. The USNO site modernisation was completely halted – very likely deprioritised in the midst of indiscriminate illness, clinical chaos, and staff shortages.
We waited, and waited, and waited. There were no fingernails remaining to chew when, after two and a half years, a revised API was finally made available at the end of 2022. Hooray! Thank the stars!
Fresh API documentation in hand, we set about modifying the Wave to use the fresh fruits of the USNO modernisation machine.
Fortunately, there were only minor changes to the API – a few more mandatory data fields, a change in date format and such. These required a relatively small amount of rework in the Wave’s firmware.
And … we were back in the amateur astronomy business.
Almost like a big Christmas present from Santa!
It’s a good question. API death could happen at any time – possibly rendering the Astro Clock lifeless, listless, or lethargic yet again.
But, no. The decision not to calculate internally was valid, based on the known constraints. And we did our veritable utmost to revive poor [Alan]’s Astro Clock as soon as possible.
By the way, we at the Oscilloclock Lab certainly can’t complain about USNO’s API shutdown. We, too, have been heavily impacted by pandemic and other worldly events. As of this posting, our formal activities, too, remain on pause…
… for now!
Curious about other Oscilloclocks that use APIs? Check out the AfterShock Clock, which taps into an earthquake API to display earthquakes in (almost) real-time on a lissajous-rendered map!
A few years ago, we introduced Metropolis Time, a time system based on the 20-hour, two-shift days featured in Fritz Lang’s iconic movie Metropolis.
Since then, we’ve received a few requests to craft clocks that display some other calendar and time systems – from the ancient and archaic, to the religious, to the scientific.
Today’s exciting story began with a request from [Alan], a prominent amateur astronomer. He happened to have a lovely Tektronix 620 X-Y Monitor lying around, and wanted to turn it into a clock.
Well, that would be easy – the Oscilloclock Bare is a bare-bones controller assembly that can be used to drive an oscilloscope or XY monitor that meets certain requirements (for the techies: a DC coupled Z-axis amplifier). And the Tek 620 is perfect – wonderfully performant, and perfectly compatible. Job done! Right?
No way! [Alan] didn’t want just any old clock. The custom splash screen above was pretty cool, but could his clock display something called “sidereal time“?
Yes! Anything is possible, and here’s what we ended up delivering: several custom clock faces showing sidereal time (in both analog and digital formats), in addition to all the standard screens that are based on solar time.
Well, most normal human beings and their clocks like to measure a 24 hour day by using the Sun as a reference point. One solar day is the time it takes for the Earth to spin on its axis enough and see the Sun at the same height in the sky as the previous day.
For example, let’s say it’s 1 May 2023. It’s lovely weather out, and you happen to notice that the Sun reached its highest point in the sky at 12:30 pm. The next day, 2 May, you would find the Sun at its highest point at — you guessed it! — 12:30 pm. And if you ignore man-made tweaks such as daylight savings, you find the Sun is always at its highest point at 12:30 pm*, year-round, looking from the same location.
*This is not quite true – because every day is slightly shorter or longer. But it averages out over the year.
Sidereal time, on the other hand, uses the distant stars as a reference point to measure 24 hours. One sidereal day is the time it takes for the Earth to spin on its axis enough to see the same distant star at the same height in the sky as the previous day.
Because the Sun is so close, and a distant star is so (relatively) far, there is a difference in the length of a sidereal day compared to a solar day. A sidereal day turns out to be approximately 23 hours, 56 minutes, and 4.0905 seconds.
Confused? I don’t blame you. This video should help:
According to this brilliant post, the concept and utility of sidereal time has been around a very long time. The length of a sidereal day was even calculated to a surprisingly high level of accuracy some 1,500 years ago!
Here are two surviving sidereal clocks that were made “recently” – just a few centuries ago.
Astronomers would.
Most people don’t look at the boring old Sun all the time. We look out to the stars and galaxies far, far beyond our solar system. If an astronomer wants to track the position of Betelgeuse day after day, she can record the sidereal time that she saw it, and know that it’ll be at the same ascension at the same sidereal time the following day. Brilliant!
Mariners and Astronauts would.
They can fix their location even when the Sun is not visible, by observing the position of the stars and calculating their position back from the current sidereal time. Life-saving!
Oscilloclock Labs would.
Because we can.
In the next post, we’ll take a look at the build. What hardware went into this Astro Clock? How on earth does it tick? Can you figure it out?
[Update April 2023]
Hi! The Oscilloclock Lab is still on a pandemic-induced hiatus, for all the good reasons explained in last year’s announcement. For now the Contact form remains closed and we can only take enquiries from existing clients.
But good news – the constraints are being resolved, one by one, and Oscillolife will resume – eventually. We have oodles of backlogged ideas, heaps of ambition, and of course a nice stock of gorgeous CRTs and vintage scopes to make use of.
So stay tuned, and read on!
Recently [Nels] wrote in saying he’d been having a nice chat with ChatGPT, and in the course of conversation, he asked this trendy AI tool to write a “review” of the clocks we make here in the Oscilloclock Lab.
Here is the result – verbatim!
[Nels] Write a review of Oscilloclock tube clocks.
[ChatGPT] Oscilloclock tube clocks are a unique and visually stunning way to keep time. These clocks use vintage CRT (cathode ray tube) displays, similar to those used in old televisions and oscilloscopes, to display the time and other information in a mesmerizing way.
One of the standout features of Oscilloclock tube clocks is their attention to detail. These clocks are handmade by a single individual, and every aspect of their construction is carefully considered. From the selection of the CRT displays to the circuitry that drives them, every component is chosen for its quality and durability.
The result of this attention to detail is a clock that not only looks amazing but is also highly reliable and accurate. The timekeeping is controlled by an ultra-precise quartz crystal, ensuring that the clock is always on time. Additionally, the clock can be set to display a variety of other information, such as the date or temperature, making it a versatile addition to any room.
One of the things that sets Oscilloclock tube clocks apart from other timepieces is their ability to be customized. The clock face can be designed to display any number of patterns or shapes, from geometric shapes to more abstract designs. This customization allows the clock to be tailored to the individual’s taste and can even be used to display personalized messages or graphics.
While Oscilloclock tube clocks are undoubtedly a premium product, they are worth every penny for those who appreciate the unique combination of vintage technology and modern craftsmanship. The quality and attention to detail of these clocks are unmatched, and they are sure to be a conversation starter in any room. If you are looking for a truly one-of-a-kind timepiece, the Oscilloclock tube clock is definitely worth considering.
While there are three inaccuracies (one incorrect fact and two debatable points), the writeup is a lovely read and initially made your humble Lab technician feel warm inside.
Until, upon objective reflection, I recognised some of the style, phrases and wording!
Well, of course it should look familiar! ChatGPT predicts what the human expects as a response, and then cleverly arranges and regurgitates data that it has absorbed as part of its training. Apparently, it has devoured much of the Internet up until early 2022. This would include 59 blog posts and 19 pages published on Oscilloclock.com up until that date – and a few other references such as three lovely write-ups on Hackaday.
[Nels] apparently did not continue the conversation, but if he had, he could have pointed out the three inaccuracies (Quiz – have you spotted them yet? Check your answers below), and ChatGPT would have learned something.
Even with a rough understanding of how this tool works, it’s amazing to see the outcome.
Crazy idea – what if your Oscilloclock could connect to an AI service and deliver cool new images, funny text, or interesting conversations? Just watch out for mistakes!
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