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Showing posts from March, 2010

Squaring two digit numbers in your head

All my life I've done mental arithmetic the 'wrong way': I've calculated from left-to-right, instead of right-to-left. So when I do something like 24 + 35 I'll see the 50 first and then the 9 . This even applies when there's a carry and I'll do something like 36 + 56 as 80 + 12 . I do the same thing for multiplication as well. Turns out I'm not so weird after all (well, apart from the finding doing mental arithmetic fun bit). I've been reading Secrets of Mental Math: The Mathemagician's Guide to Lightning Calculation and Amazing Mental Math Tricks and the author, Michael Shermer, is just like me: he works from left-to-right. He, like me, has found this to be a good system because it lets you discard digits early and not hold some enormous calculation in your head. For example, in the calculation 124 + 353 you can immediately say "four hundred" before doing the rest of the sum. This seems to free up headspace (at least for m

Goodbye HP Procurve Access Point 420

Over a year ago I discovered a bug in an HP ProCurve Wireless Access Point 420 that we were using in our office . After being treated badly by HP I finally got support from them by blogging my frustration and ending up on the front page of Google search results for procurve support . Eventually, weeks later, HP acknowledged the problem with the device. But this story doesn't have a happy ending. In November 2009 HP informed me that the product was being end of lifed . Out of curiosity I called HP Procurve Support and asked them about the status of my case and they couldn't even look up my case number. Searching around with my name they did manage to find me and my case was active and open. The latest update was on March 19, 2010 and the case had been escalated to Level 3 Support. My previous experience with HP support wasn't good, but this time Derek was great. He tracked down the ancient case, updated me with information, updated contact information for me. An

London Transport Museum: Acton Depot Weekend

This past weekend the London Transport Museum held an open weekend at its Acton Depot where they keep a collection of trams, trolley cards, buses and underground trains, plus all the associated equipment. They only open the depot twice a year so this was a chance to see some things that are rarely open to the public. I didn't include this museum in The Geek Atlas but after a visit it's likely a candidate for a volume 2 since it is packed with interesting stuff. Like a really big collection of old underground signs: Or shielding used while constructing the tunnels for the London Underground: And speaking of the Underground, here's a power control panel with meters indicating hundreds of amps and some serious on/off switches: And a lovely mercury arc rectifier used to turn AC into DC (the Underground uses 630V DC power). And here are the wheels of a 1930s trolley car: And here's the control panel from an Otis elevator: But the highlight was a ride on t

A welcome bunch of amateurs

Here's me writing in The Guardian's Comment is Free section: We're all the children of amateurs: amateur parents. There's no government department that will certify you as a parent (thankfully), nor a university department where you get your PhD in being a daddy, nor a professional body ready to strike you off for not following mothering standards. But any parent who's held a newborn child in their arms has unconsciously taken the amateur's oath: "I may not be a professional, but I'm going to do whatever it takes to act like one." You can read the rest here .