Building an observatory. Construction #37

This weekend was grey and dreary and after a couple of hours of horizontal rain on Sunday I wasn’t really keen to go out and do much work on the observatory, especially as I really wanted the roof open so I could see what I was doing. Eventually however I found a little enthusiasm and sat in the semi-darkness (without rolling off the roof) measuring up for the first sheet of flooring. With one eye on the sky I hurried to get a sheet of my 18mm ply cut to size and having shifted all the tools back under cover took the sheet down to the observatory and dropped it into place, to relief and pleasure in equal amounts when I found that it dropped over the first block of the pier very nicely.

All of which reminds me that I’ve not given much detail of the piers recently, nor the ducting for cables. I’ll do that another time as I need to fit more ducting anyhow.

Meantime, a photo of the first part of the floor to go in. I have no idea how the leaf managed to get there…

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Ubuntu 64-bit ARM beta missing package niggles

This week I downloaded the Ubuntu 64-bit ARM beta image to try out (and so I could test building oacapture against the 64-bit ARM environment). It booted neatly, but I got a bit stuck when I tried to install the various development packages that I needed to do my build.

The first problem was that APT couldn’t find the linux-libc-dev package to install. I hadn’t required this, but it was a dependency for the other development packages I wanted. Eventually I thought to look on the repository servers and whilst I couldn’t find the version APT was trying to install, I did find one for the same kernel with a very similar version number, so I did:

# wget http://ports.ubuntu.com/ubuntu-ports/pool/main/l/linux/linux-libc-dev_4.15.0-43.46_arm64.deb
# dpkg -i linux-libc-dev_4.15.0-43.46_arm64.deb

There were no errors on the installation, so we’ll see what happens when I start using it.

The second problem was very similar, but this time the package that couldn’t be found was libcups2.

Again I found a similar version in the repository, just a couple of point releases higher. To get this to install however, I also needed some of the avahi packages:

# apt-get install libavahi-client3 libavahi-common3 libavahi-common-data
# wget http://ports.ubuntu.com/ubuntu-ports/pool/main/c/cups/libcups2_2.2.7-1ubuntu2.2_arm64.deb
# dpkg -i libcups2_2.2.7-1ubuntu2.2_arm64.deb

Again there were no errors once everything was installed and I managed to download and install all the other packages I required without a problem.

I’m assuming this is just a minor error with the package lists for the beta release and will eventually be corrected, but it’s allowed me to make progress with my own code without having to try the 64-bit ARM ISO that looks to require far more work to get into a usable state.

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Swimming, 11th January 2019

Forced myself back to the pool today despite not really feeling on it thanks to sleeping badly last night. And I’d have to admit that I didn’t really swim as well as I felt I could. However, repeating yesterday’s set I still managed to improve my performance, failing first on rep 15 and then again on rep 24. It would be nice to think that if I can get back to the pool on Monday perhaps I can eliminate that second failure. I can’t deny that it’s very tough though.

USRPT distance this year: 12,100m
Total distance this year: 12,100m

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TYR Velocity goggles update

Disappointingly, on their third outing my new TYR goggles persistently misted up. No idea why. They’d been fine the first two times and I rinsed them in clean water and kept them in a hard case when not being used, but on my third session they were misting up within fifteen seconds of being put on, which made it quite tricky to read the pace clock.

I’m sure natural oils from eyelashes and skin contribute to the problem of misting up, but I wonder if the water temperature also makes the problem worse? The pool where I normally swim is an early 70s “warehouse” design with minimal insulation, and on cold days such as we’ve had this week there’s a noticeable drop in water temperature despite the pool cover (which I assume is put on every night).

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Swimming, 10th January 2019

Back to the pool today with a new, faster, target, fully expecting it to be quite tough. I wasn’t wrong this time, either. It really was hard work. Had my first failure on rep 12 and another on 20, but after that managed to keep going to the end. Back tomorrow (hopefully) to see if I can get a little further.

USRPT distance this year: 10,400m
Total distance this year: 10,400m

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TYR Velocity goggles first impressions

As I posted last week, I was in need of some new goggles to replace my TYR Racetech pair and ended up purchasing three sets: TYR Velocity, Arena Tracks and Nike Remora, all with clear lenses as the pool I usually swim in is not very well lit and has no natural light.

As the strap on the Racetech goggles had just failed I thought I’d try the Velocity ones first. I’ve now done a couple of sessions with them. They’re a more streamlined design compared with the Racetech pair which had lenses that protrude a fair bit more. Initially I thought that design would help with misting up as I felt that at least some of the problem was due to natural oils transferring from eyelashes to the inside of the lens. It didn’t seem to make any significant difference though, and in fact I found that the lack of streamlined design meant that water tended to drag at them more when pushing off the wall.

Unlike the Racetechs, which appear to have a rubber strap, the Velocity pair have a pair (or rather, two loops) of what looks like a silicone strap, secured by a single adjuster at the back rather than one each side of the eye. The rubber strap was comfortable and didn’t obviously appear to slip, but I don’t think repeated immersion in chlorinated water really did it any good. The single adjuster on the new pair also appears to hold its position well.

One of the things I really did like about the old pair was that they gave quite a good view around me. I have an emergency pair of Speedo goggles that are like staring down a pair of pipes by comparison. The new ones are almost as good. There’s probably a little less definition to the sides because of the shape of the lens, but it’s still possible to tell that something is there. In fact whilst swimming I’m not aware of the presence of the eye gaskets at all, perhaps helped by the fact that they’re also clear.

The only two niggles so far have been that the adjuster can get caught in my hair and that when I take them off it’s clear that the right hand lens has been digging into the side of my nose slightly, though I’ve not been aware of that at all whilst I am swimming. It’s possible that using a wider nosepiece might help, but as the fit is otherwise very comfortable I’m going to leave things a little longer before attempting to change anything.

Unlike many of my previous sets of goggles, none of the ones I’ve bought this time around come with a storage bag or case, though for me that’s not a big deal as I prefer to keep them in a hard case anyhow.

Overall I’d say I’m quite pleased with this pair so far. Mostly I can just forget they’re there whilst I’m swimming which is exactly what I want. It remains to be seen how they perform over a longer period, and in particular how long it takes them to start fogging up.

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Swimming, 8th January 2019

I arrived on poolside today to find a number of slow(er than me) swimmers taking up multiple lanes. Fortunately the lifeguards were happy to make another lane for me. I don’t relish the prospect of piling into some lady twenty years my senior swimming at half my speed 🙁

Anyhow, another reduced interval for my session today, which meant I was expecting it to be tough going and was aware that I might struggle to get through the entire set. I wasn’t wrong either. I was pretty much on the limit as the set progressed, still breathing fairly heavily by the time I started each new rep. Somewhat to my surprise however I did in fact get through the entire set, though walking in a straight line was quite demanding once I climbed out of the pool 🙂

That means another reduced interval for next time. Given how tough I found it today I think getting all the way through another set immediately might be asking too much, but we’ll just have to see how it goes.

USRPT distance this year: 8,700m
Total distance this year: 8,700m

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Swimming, 7th January 2019

A repeat of Friday’s session today, with the advantage of new goggles, despite feeling quite tired and not really wanting to go thanks to not sleeping very well last night.

As things turned out however, once I got going it actually went pretty well and I completed the entire set, so hopefully I’ll be back tomorrow having reduced the interval yet again. I suspect it’s going to start to get much tougher fairly soon.

USRPT distance this year: 6,900m
Total distance this year: 6,900m

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Building an observatory. Construction #36

It certainly wasn’t warm out there today, but armed with some newly-purchased stainless steel screws I decided to get on with the cladding on the sides of the roof. To do that it was necessary to open the roof which I’ve not done in what seems like ages, so whilst it was open I took a rare daytime photo.

As usual it took rather more time than expected to get the cladding into place, mostly because I was trying to be very careful to avoid fouling any of the structure as the roof opens and closes whilst keeping the gap between the sides of the roof and the wall as small as practical. Another minor little issue that I should have identified sooner also tripped me up: stainless steel screws are not magnetic, so they don’t stick on the end of the magnetic driver bit that I have for my drill/driver. This left me needing to use all three hands to hold the wood, the screw and the drill. And that’s when I noticed the problem 🙂

By the time it was too dark to work I’d got most of one side done. It really was quite dark, too. The chickens had all taken themselves to bed before I’d even finished tidying up. There’s no rain forecast for tomorrow so hopefully I can get out there again and it will be quicker having sorted most of the difficult bits today, which should allow me to finish most of it off and perhaps even start on the flap in the southern gable.

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Swimming, 4th January 2019

A tough session today, dropping my rest interval down again and already feeling very tired in the arms. I plugged away but eventually failed on rep 16, so hopefully I can do better next week.

USRPT distance this year: 5,100m
Total distance this year: 5,100m

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