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Registered Member #1938
Joined: Sun Jan 25 2009, 12:44PM
Location: Romania
Posts: 701
I see. Well then, looking forward to see it ready.
Last time I checked Farnell probably I didn't consider the SMDs, and a 100GO is still expensive. But now I see there are the 50G (SMD) resistors for 1.22GBP quite a good alternative.
Registered Member #543
Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992
radhoo wrote ...
I see. Well then, looking forward to see it ready.
Last time I checked Farnell probably I didn't consider the SMDs, and a 100GO is still expensive. But now I see there are the 50G (SMD) resistors for 1.22GBP quite a good alternative.
It's easy to 'tack' two 50G in series with solder to make 100G if you want to, and to solder some wire tags onto the ends, so you won't have to use them as SMD parts. In any case, at 100G the board is probably more conductive than the resistor!
Registered Member #543
Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992
Friedrich and Knipping's X-Ray Crystallography Apparatus 1912
On April 12th 1912, at Ludwig-Maximilians University, Munich, Friedrich and Knipping used this simple apparatus to reveal the pattern of dots produced by the passage of X-rays through a copper sulphate crystal, in order to test a theory of Max von Laue (1879-1960), Paul Knipping's tutor. Von Laue's mathematical explanation of the Laue-Friedrich-Knipping phenomenon earned him the Nobel Prize for physics in 1914.
Wooden uprights from a blackboard easel, a kitchen table, and roofing lead have all found their way into the construction. The system of pulleys for raising and lowering the lead shielding box reminds me of the guillotine.
Registered Member #543
Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992
Steve McConner wrote ...
Very nice! I hope you're going for the same steampunk style in your own spectrometer.
I think it's wonderful, Steve, and I've since realised that the round brass plate at the heart of the instrument is the stage from a polarising microscope.
I wonder what was used to power the magnificent tube? A large induction coil perhaps...
Registered Member #543
Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992
George Schmermund wrote ...
Here's a site where someone is really into their ion chambers!
No disrespect to you or Charlie Wenzel, who is a decent fellow, but you'd never get one of those contraptions to hold to a calibration standard for five minutes. As my project thread is all about measurement, it really isn't the place to debate the offerings of other web sites, no matter how great their merits may well be:
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X-Ray Spectrometer
