Fixing Lomo UPB-1A upper spool shaft / bolt /screw – for good.

So, the infamous Lomo UPB-1A upper spool shaft / bolt /screw…

It failed, didn’t it? The M10 screw snapped off at the stem right away and there’s no glue that will hold. Known issue.

There are two fixes known to me, one is botching the job, is rather easy, but will fail some time soon. The other solution is to manufacture a replacement, but it is a bit more trouble.

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Running third party motor with your Mindstorms EV3 / NXT

Mindstorms EV3 and their motors

The LEGO® Mindstorms is a very nice compact and easy to program set, with a lot of sensors (both, LEGO own as well as third-party, see e.g. http://www.mindsensors.com/).

When talking about motors, the air gets thin pretty fast. I mean, the LEGO own motors are cool, but there are only two sizes that are compatible with EV3 and the bigger one has rather sloppy gears, so although LEGO claims it has 1° of accuracy, it has easily 10° of (undetectable) backlash, meaning it can be considered halfway precise only if it is always loaded in the same direction – which for a two-wheeled tank-style robot is never the case.

So it got me thinking: how hard can it be to connect a third party motor?

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Hantek DSO1062B / DSO1102B / DSO1202B vs. 5GS/s LeCroy Waverunner ;)

What is it about?

I have read all too often about things that are supposed to be just as good but ten times cheaper. I’m not a fool. Even though cheap tool can often do the job, I can see the difference all the same. However, often a compromise has to be made.

While at my day job, at my workbench, I can have a nice LeCroy Waverunner, it’s hardly something I enjoy lugging around in field. For field use I want a handheld scope. It has to run on battery, has to be reasonably rugged, and so on. However, at the same time, with portability comes stealability, droppability, wettability and all world-happened-abilities that seem to be present outside of the nice, dry, warm lab. Field equipment has to be a compromise between usability and price.

Since I have bought for my own hobby workshop a chinese-made handheld scope, I thought I’d compare it to a bench LeCroy anyway. I want to focus on what signal faults I’m blind to when using the handheld at home. The difference between a Mercedes SLK and a Fiat Panda is obvious, both in price and in comfort, but the both get you there, don’t they? But if the road is bad, how much worse are we off in the Panda?

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Yunnan 2008

Photos posted here: http://www.flickr.com/photos/mareklew/collections/72157629307257293/

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Some archival shots from India are online

Posted here: http://www.flickr.com/photos/mareklew/collections/72157629375853431/

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