What I Learned Today

Before text-to-speech, there was the optophone. It scans the letters in a text and converts them into chords that represent the visual shape of the letter. Instead of hearing someone speak the text, you hear what the text looks like.

This invention was published in Nature in 1914 (!). (By the way, there’s a bit of delicious irony in the disclaimer attached to the 1914 article in its current digital form: “This text was harvested from a scanned image of the original document using optical character recognition (OCR) software. As such, it may contain errors.”) You can access a PDF scan of the original paper for the full details, including the claim that the device “should, with some practice, enable totally blind persons to read ordinary books and newspapers through the sense of hearing.”

The device conducts a horizontal scan, with 8 “dots” moving in parallel across the letters. Each dot is assigned to a different tone. With no input (totally white background) all the dot-tones are active. When a dot crosses a dark region (text), its tone disappears, so the sound changes. I think they must have inverted this plan later, to turn on the sound when a dark part appears, based on the examples.

With practice, in theory you can learn to “read” words by their tonal patterns. Give it a try! This is the optophone “reading” the letters f, i, k, j, p, q, r, and z:

Not super harmonic, but I can see that it’s possible to distinguish letters. However, it’s a slow way to read, even after practice, which led to the development of more “compressed” versions. In general, the goal wasn’t necessarily efficiency, though – it was an attempt to make available the large volume of existing printed matter to those who could not see, without requiring a translation to e.g. Braille first. Neat invention!

Morse code just got 10 times cooler – or maybe just 10 times easier to learn!

A few years ago, I stumbled on the mind-blowing binary tree version of Morse code. I was so excited about this that I downloaded a “learn Morse code” app on my phone and started practicing it, gradually working up to faster comprehension speeds. But then I got distracted by some other shiny thing and stopped practicing and Morse code went dormant in my brain.

Two days ago I re-encountered it in this amazing video by the always impressive Nelson Dellis:

Nelson gives us mnemonics for learning Morse code. This is absolutely BRILLIANT since Morse code is already audible. :) After watching his video exactly *once*, I already know Morse code for my name and can recall it with negligible effort:

-.- .. .-. ..

(mnemonic: KAN-ga-ROO i-bid ro-TA-tion i-bid)

*and* I discovered a beautiful symmetry in my Morse name!

I’m truly impressed by how quickly and easily this mnemonic sunk in. Nelson, you rock!

On Saturday, I flew to the Perris Valley airport (L65) for the first time.  The flight out at 5500′ was uneventful and rather quiet for a Saturday; I didn’t have any nearby traffic.  Perris is 44 nm from El Monte, or about 30 minutes of flying. I had the usual fun trying to spot a new airport — it’s not as easy as it sounds. Here’s the Google Maps 3D view which simulates about what it looks like as you fly in, hunting for the runway. Can you see it?

Perris Valley doesn’t have a tower, but there’s a guy on the radio (CTAF = Common Traffic Advisor Frequency) coordinating jumpers and planes. He was very friendly when I first called in and asked if it was my first visit, and then gave me a lot of helpful tips, including a wind check and guidance about where transient parking (for airplanes) is. I made right traffic for RW 15, bypassing the first 1900′ of dirt in favor of the asphalt for landing.

After landing and parking, I stepped out of the plane and felt a shadow cross over me and looked up to see a cluster of jumpers coming in to land over my head! Transient parking is right next to their landing field, which is just east of the runway. Obviously this could create some issues, and they clearly were busy keeping things safe and managing airplane and skydiver traffic together. In addition to my Cessna, there was a light sport aircraft that landed right after me, and two large planes with shark faces painted on that were doing formation takeoffs.

I walked (quickly and carefully) across the runway to the Bombshelter Cafe, where I had a tasty BLT and sat at a window to watch the periodic rain of skydivers coming in. I’ve never jumped out of a plane myself, so it was interesting to watch the range of techniques they use to come back to land. Some jumpers flared so lightly that their feet just brushed the grass before they settled down into a quick walk, parachute sinking and deflating behind them. Others came in fast, stuck their legs out straight, and landed butt-first, skidding along with the parachute dancing behind them. I can already say which landing I would prefer. :)

At right is a picture of the plane they use to take the jumpers up (a Short SC-7 Skyvan). It is fat and wide and squarish. It’s a twin-engine plane that sort of wallows its way into the air. Apparently it has good short landing properties, which is probably useful at Perris, since the paved runway is only 3200′ long. (Plenty long enough for me, natch.)

After lunch, I got the plane ready to go, but just as I was going to start the engine, another cloud of jumpers came raining down. In a bizarre coincidence, just that morning I read this article and therefore was on high alert. To be safe, I wanted to check in with the CTAF guy before starting my engine, so I pulled out my handheld backup radio: “This is the Cessna in transient parking, ready for departure. Is this a good time to start up?” He said it was fine, so I started up and followed instructions to back-taxi on RW 33 (the wind had changed to the north) and exit at the actual taxiway so I could do my engine runup. I then taxied up to the RW 33 threshold and declared that I was taking off with a left crosswind departure. The CTAF guy said “I’ll hold the jumpers here until you’re away,” which I appreciated. It still feels a weird and uncomfortable to have people walking around so close to an active runway! More high alert!

My flight back at 4500′ was also uneventful, although the first SoCal controller rejected my request for flight following because he was too busy. The second one picked me up and I cruised through Ontario’s airspace direct to El Monte. Overall, a fun lunchtime excursion!