Friday, December 16, 2011
Wednesday, July 20, 2011
Cycle Helmet - or not?
Just finished looking at cyclehelmets.org, a site which claims that wearing a helmet while cycling does not reduce the chance of serious head injury. Hmmm - despite the "scientific" claims and expert opinions, there is rather biased and distinctly non-scientific analyses of their data sources. "Helmets don't work" is obviously a preconceived idea.
As always with such matters, the truth is not entirely clear - but I have a simple approach. Dear cyclehelmets.org oh-so-clever engineer, put on a helmet and get a friend to hit you increasingly hard on the head with a baseball bat until the blows on your helmet are "uncomfortable." Now take it off and let him hit you directly on the skull. Now look at your helmet - I bet there will be no sign of your engineer's "compression." What does this prove? Your website is flawed, so for me ... I'm wearing a helmet.
As always with such matters, the truth is not entirely clear - but I have a simple approach. Dear cyclehelmets.org oh-so-clever engineer, put on a helmet and get a friend to hit you increasingly hard on the head with a baseball bat until the blows on your helmet are "uncomfortable." Now take it off and let him hit you directly on the skull. Now look at your helmet - I bet there will be no sign of your engineer's "compression." What does this prove? Your website is flawed, so for me ... I'm wearing a helmet.
Friday, July 08, 2011
DIY HiFi
Another project looms ... a SET amp using 45 output tubes. These are arguably the pinnacle of hifi amps, but at a measly 2 watts or so need extremely efficient speakers. Guess what - I have such speakers! Onward we go ... research stage ...
Tubelab SE?
Pros: plenty online help, pcboard, reviews all positive.
Cons: apparently rare input tubes (5842) - could find them though. PCB - would be nice to do a point-to-point. Needs a few components eg ICXP 10M45S IC (no suitable alternative apparently) that are extraordinarily difficult to source in the UK.
Still looking ...
Tubelab SE?
Pros: plenty online help, pcboard, reviews all positive.
Cons: apparently rare input tubes (5842) - could find them though. PCB - would be nice to do a point-to-point. Needs a few components eg ICXP 10M45S IC (no suitable alternative apparently) that are extraordinarily difficult to source in the UK.
Still looking ...