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Proud Mary

Mon Oct 11 2010, 03:44PM

Registered Member #543 Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992

GM Prospector with accessories

1286811289 543 FT0 Gmprospector Kit Final Choice

32 ohm single earphone and gamma probe

And in its carry case

1286811320 543 FT0 Gmprospector Kit Packshot Final Choice

IntraWinding

Tue Oct 12 2010, 11:57PM

Registered Member #2261 Joined: Mon Aug 03 2009, 01:19AM
Location: London, UK
Posts: 581

Excellent! Time I got back to my version too, now the nights are drawing in...

How about slapping one of these on the back

803

Wed Oct 13 2010, 01:52AM

Registered Member #2807 Joined: Fri Apr 16 2010, 08:10PM
Location:
Posts: 191

I ain't afrait of no gosts!

Arcstarter

Wed Oct 13 2010, 03:41AM

Registered Member #1225 Joined: Sat Jan 12 2008, 01:24AM
Location: Beaumont, Texas, USA
Posts: 2253

It's so beautiful. Makes me want to cry!

Now i need to get a tube and make a Geiger counter. Which, i have a question about such meters... Would a Geiger counter work well with flash X-rays? You seem to have alot of knowledge on the subject :)

Proud Mary

Wed Oct 13 2010, 07:48AM

Registered Member #543 Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992

IntraWinding wrote ...

Excellent! Time I got back to my version too, now the nights are drawing in...

How about slapping one of these on the back

Oh I think this is more my style of hazard sign:

1286955920 543 FT0 Saltwater Croc Warning Sign

Proud Mary

Wed Oct 13 2010, 08:52AM

Registered Member #543 Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992

Arcstarter wrote ...

Would a Geiger counter work well with flash X-rays?

Totally hopeless!

A GM Counter does no more than count events that happen in a GM tube. Huge events, or very small events, it counts them just the same.
It gets hit by a cosmic ray of awesome power, it goes click.
It gets hit by another photon so feeble it barely makes it through the tube's case, and it clicks just the same.

So in the case of a flash X-ray burst, the counter will go click once.
There will be no way that you can tell that the one click you've heard wasn't just part of the background count that all GM Counters register all the time,
or even one of the false counts that happen at random in this type of detector. Or the click might even be caused by the counter acting like a radio receiver, and picking up the electromagnetic pulse radiating from the flash X-ray power capacitors as they discharge violently.

I have no personal experience of measuring super short single X-ray pulses, but do know that thermoluminscent devices - TLDs - are often used. But these devices require a sophisticated, costly, reader instrument to be of any use.

A penetrameter made from a 20-blade mechanic's feeler gauge is probably the easiest way to estimate the energy of a single X-ray pulse. How thick a piece of steel will reduce the X-ray dose to a piece of photographic film by one half?

Steve Conner

Wed Oct 13 2010, 09:14AM

Registered Member #30 Joined: Fri Feb 03 2006, 10:52AM
Location: Glasgow, Scotland
Posts: 6706

A lovely wee homebrew!

Proud Mary, sorry to go off topic, but have you ever tried the other colours of Hammerite? I want to try the gold stuff on the speaker grill of a retro-looking amp I'm building, but the hammered gold only comes in a tin that you have to apply with a brush, and I'm worried it'll look awful.

Proud Mary

Wed Oct 13 2010, 10:01AM

Registered Member #543 Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992

Steve McConner wrote ...

A lovely wee homebrew!

My crude photography doesn't do justice to the Hammerite black I used on this instrument case. To the naked eye, in normal daylight, the deep black is relieved by tiny irridiscent particles, just enough to breathe some visual life into it, without drawing too much attention to itself.

I have tried the spray version of Hammerite Direct to Metal "Hammered Dark Blue" on other instrument cases. It came up as a slightly metallic blue, with a more subtle hammered texture than the brush-on Hammerites, though I don't think it has the same abrasion and scuff resistance, which is the main reason for choosing this kind of industrial paint.

I understand your doubts about 'gold' paint, which can often look really ghastly. If spraying were impossible, I think I'd give it a go with quite a dry brush, so the paint couldn't start accumulating in the corners of the perforations.

But as there is a Hammerite Smooth Direct to Metal Aerosol Gold 400ml, I think I'd give that a try first!

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