Week 119: Quantum locking
I had a couple of vivid but weird dreams. In one, I was walking along a road near our house, when I met a group of anarchists in a flying bus. I went back to their squat/workshop, where they explained to me how the levitation worked. I said, like when you put a superconductor in a magnetic field? They said yes, it’s quantum locked.
L— and I spent Saturday afternoon in Nene Park with her parents, brother, and family, as a sort of convenient mutual midpoint. It was muddy underfoot, but sunny and pleasant.
To get there, we had to take the train to Peterborough. When I first looked at tickets, they seemed very expensive, and you had to commit to a specific train to avoid paying even more. But with a bit more research I found that we could just take the Thameslink service from London Bridge for much cheaper, whenever we liked, and by avoiding the need to get to Euston on the Underground, the difference in time compared to the nominally faster train was minimal. Every time I travel by Thameslink I’m impressed by how cheap, frequent, and convenient it is compared to other services in this country.
For the first time, I used the new QR code National Rail tickets, bought in advance, which saved time at the station. They’re not actually new, but it’s only recently that I’ve seen the readers everywhere. I’m told that the purchasing experience varies depending on where you buy them. I bought the tickets on LNER’s website because I already had an account there. The one place I don’t buy tickets is Trainline, because I refuse on principle to pay a booking fee for something that can be bought without one elsewhere.
I was impressed with the implementation: you get the option to print the ticket,
or you can have it emailed as an Apple format pkpass
file or the Google
equivalent. Although I have an Android phone, I’ve never managed to get the
Google wallet tickets to work, so I always use the Apple ones with
PassAndroid. I appreciate the fact
that you don’t have to have a specific app or even a mobile phone.
I scored a broken Korg Monologue for a bargain on eBay, and had it fixed within a few hours of receiving it. The described problem was that the tempo knob was erratic. I thought that sounded like a failed potentiometer. When I tried it out, the potentiometer was stable at its lowest and highest values, but fluctuated widely anywhere in between, which seemed to confirm my remote diagnosis.
All the front panel controls are scanned by a microcontroller which feeds parameters to the synth engine, so all the potentiometers are the same 10 kohm that you usually find serving this purpose. However, after looking on every electronic vendor website I could find, I wasn’t able to find the specific physical configuration of 16 mm pot Korg used. I could find ones with the same legs and body but a different shaft, or the same shaft but not through hole, or ones that wouldn’t fit at all.
I already had smaller 9 mm versions with the correct shaft, but they wouldn’t fit the circuit board. But that was a relatively easy problem to solve: I 3D printed a jig for alignment and soldered on some stiff copper wires to extend the leads.
With everything reassembled and the potentiometer firmly attached to the front panel, the repair is invisible and the synth works perfectly.
I paid someone seventy quid to cut my toenail and it was money well spent. A side effect of getting too hot during the 45 C heat last summer is that my toenails went weird. They stopped growing and started again underneath, leaving a stub of the old toenails to grow out over the course of about seven months until those fell off leaving new but slightly ragged ended nails beneath. In the past few weeks, this led to irritation, bleeding, and a painful area of hypergranulation beside the nail of my big toe.
The solution was to cut away a tapered triangle to stop the nail from causing irritation. This has done the job, and everything is settling down to normal. With luck, the nail will grow out normally this time, this summer won’t be as hellish, and it won’t happen all over again.
I cooked this vegan quiche recipe (using pre-made pastry and replacing the spinach with rocket as we had a surfeit) and it’s amazing. Not too much work, and great results.