Observations with a crystal

On a sunny day (Mon, 24 Oct 2011 13:38:36 -0700) it happened snipped-for-privacy@radagast.org (Dave Platt) wrote in :

All very interesting arguments, but I hardly think BC548-B and BC558-B, with an ft of about a few hundred MHz would qualify as microwave detectors. I have a nice microwave detector, to check my microwave oven though, it is tuned I think. You need a good microwave diode for something like that. No, I do not think this was radar, and the way the spectrum formed indicated some isotopes, but it was not calibrated at the time so I do not know which ones.

On a sunny day (Mon, 24 Oct 2011 16:16:17 -0500) it happened Jon Elson wrote in :

(dials) painted with radium.

highway.

Sure, old military and even civilian planes are dumped somehere. No it was not long ago, I tried looking for that text in that group, but could not find it. I do remember indeed a long time ago radium painted watches were made illegal here.

I also stayed somewhere as a kid, and they had real radium containing light switches, I was told: do not touch that, it is radioactive... In those days radium was everywhere, you could even buy radium containing drinks. Untill a well known baseball player (?) died from it and they had to bury his bones in a lead box... Where did al the radium go? Landfills? You should read that yahoo group for a while, or just ask there, may shine a green light :-) How about uranium containing glass? We had plenty of that at home. I liked the color (greenish yellow). You can still buy that on ebay, vases, dishes, what not.

I've done that. Works fine.

John

You do *not* need a transistor with gain up in those frequencies, to detect those frequencies!

If what you say is true, a simple crystal radio (which has *no* gain at all... not even a battery) could not possibly work... and yet we know it does.

All you need is a semiconductor junction (or other nonlinear device) which still exhibits some nonlinearity at those frequencies, and a strong enough signal (enough voltage) to excite it. This "detection" of the system can produce a voltage pulse at a much lower frequency, which can then be amplified by the gain elements in the rest of your signal chain (or, simply recorded and sensed directly, as with a human listening to a crystal-detector radio via a high-sensitivity headphone).

Radar is a pulsed signal... its peak power is far greater than its average power. It's not like a microwave oven, where you're trying to detect leakage of a low-level continuous (or nearly-continuous) signal. Military-plane radars seem to operate at very high pulse powers, in order to be able to "burn through" interference and to provide high-resolution radar images from many miles away.

I fear that you are leaping to conclusions. You're assuming that your analysis output is driven by valid data... and I think you've got invalid data (e.g. external RF pulses) leaking into the very beginning of your signal chain.

I don't believe that you can trust your system to tell you what you think it is telling you, until you have successfully eliminated any possibility that other sorts of signals are leaking into your signal path.

That could be done by shielding your entire detection system in a shield which would block RF radiation, but would pass high-energy photons (e.g. X-rays and gamma) and particle emissions. A good thin-walled Faraday cage, plus proper EMI bypassing on all of your leads into/out-of the cage might suffice.

Another good analysis to do, would be to look at the actual pulse waveform coming out of the detector, to look for the kind of periodicies that you would expect to see from a pulsed radar signal.

Installing a wide-band RF receiver (one which by design would *not* be sensitive to radiation) and capturing its data at the same time, would be another way of validating what you think you are seeing.

If your crystal / PMT detector "sees" something which does not exhibit RF-pulse-like behavior, and a wideband RF receiver sees nothing at that time, then you'd have data that you could trust.

Remember one of the primary rules of scientific research: it's important to try to figure out any way that your own hypothesis could be wrong, and then test those ways and see if you can actually disprove them. Falling in love with your own hypothesis, and focusing on how to prove it right (rather than trying very hard to disprove it, and failing) is a trap that has led many enthusiasts down blind alleys.

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On a sunny day (Tue, 25 Oct 2011 11:19:32 -0700) it happened snipped-for-privacy@radagast.org (Dave Platt) wrote in :

Do not get carried away. I made an observation, and also have tested my circuit against RFI. My GSM cellphone about 30 cm away seems to have no noticeable effect on it. GPRS mode too. But of course I will run more tests.

It looks more that you are desperately looking for an other explanation than reality :-) Maybe you are afraid of that reality?

reality :-)

Nope. I've got no particular interest in either side of the question. In fact, I'd find it *more* interesting if what you are suggesting, turns out to be correct.

I'm just trying to do what good scientific practice requires: try to poke holes in any new-and-unconventional theory, to see if there's are alternative explanations for what you're observing.

As to reality: the *reality* at this point, is that you have an unusual observation.

Your *explanation* of the cause for this observation isn't yet "reality", in the sense of being well-supported or accepted. It may be correct, or it may not be... but at this point it's just a hypothesis and not yet a theory.

Jan, please don't treat those who question your methods or results as enemies.

--
Dave Platt                                    AE6EO
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reality :-)

Did you see a huge flash and a mushroom cloud? If not, the possibility that a plane flew overhead and caused strong nuclear radiation at a distance of 1000 feet seems impossible. You can work out the solid angle, and thereby the best efficiency of your detector at that distance. Clearly, the solid angle is going to be minute at that distance. So, your detector is only picking up a nearly infinitesimal amount of the total radiation from the source, which will be covering

4 Pi solid angle.

OK, in the original message, you didn't really state how many counts you got, just that it was above background. So, how many did you get? Hundreds, or hundreds of thousands?

You can also figure out the solid angle of the pilot or people who have to handle these weapons. The maintenance people have to get right up to the weapons to mount and dismount them, as well as service them. When actually touching the weapons, their solid angle is even greater that the pilot.

Well, Plutonium 239 is NOT very radioactive, at least compared to some other things that have shorter half-life. Anything with a half-life of 24,000 years must have a fairly slow radioactive decay. The Tritium in the booster of these weapons has a much shorter half-life, but there really isn't that much Tritium in them, by mass, just a few grams. Tritium is three times as heavy as Hydrogen, but that is still pretty light stuff.

OK, one other possibility is that this plane was carrying a radioisotope thermal generator for use in extremely hard to get to locations like the arctic or mid-ocean buoys, or a radioactive source like Cobalt 60, for X-raying pipes and metal parts, or medical therapy. These things DO give off some POWERFUL radiation, and shielding is nearly impossible. They usually are not transported by air in the civilian world, but the military may have different rules.

Jon

drinks.

bones in a lead box...

I have a piece of a Uranium-glazed dish, it is a brilliant orange, and makes a Geiger counter count at several thousand counts/ minute. I had a watch with a Tritium-lighted dial some years ago. Our building here at work has yellow ceramic blocks, kind of like glazed pottery bricks, that are slightly radioactive. We do nuclear chemistry here, and so have a wide assortment of detectors for charged particle and gamma radiation. If we put the gamma detectors too close to the full wall of these, we get extra lines in our spectra.

A little gamma radiation is everywhere, but you have to take care with this stuff to not inhale/ingest it. We had a source here in the safe that emitted 2+ million gammas a minute at about 600 KeV. I eventually made enough noise that is was moved to a larger safe in another building where nobody spends much time near it. Multiple lead bricks and the inch-thick steel safe had almost no effect on gamma rays of that energy. When this source was here, I could detect it from over 20 feet away with a small scintillator!

Jon

Eben Byers - he became a cause celebre in the fight against quack medicines - field in which the US had led the world at the beginning of the twentieth century. The modern slogan Coke "it's the real thing" had a far more insidious meaning at that time too (about 10mg per pint).

Mostly in watches and aircraft dials. You can still find it on WWII junk if you look hard enough. Ideal source for a DIY cloud chamber. Radium paint glows in the dark irrespective of exposure to light (although it also phosphoresces when activated with strong light).

Antique uranium glass is highly collectable because under UV it fluoresces green and it is also a very pleasing deep yellow colour. In daylight it appears to glow slightly internally from UV fluorescence.

It will. Radium watches were even more effective on Geiger counters.

19keV electrons don't make it through the glass unless you break containment so they are not really any more dangerous than a colour TV tube. Quite hard to detect them apart from by a scintillator.

Grey breezeblocks made from power station fly ash are amongst the most radioactive things sold in bulk to the general public. There is a tiny amount of uranium in almost everything and in concentrates in the assh when you burn coal - global average 2ppm in the crust with more in some igneous derived soils. Mineable ore is rare though.

Plasterboard is too since traces of calcium isotopes 46 and 48 half lives are ~10^15y and 10^19y respectively are very slightly radioactive and calcium is incredibly common in the environment .

One of the more curious paradoxes is that with the right layer steel around it to stop the alphas clean depleted uranium is actually an excellent radiation shield or generic dense metal. You can safely hold a bar of it forever protected only by a sheet of mylar film.

Also gets used for DU munitions where its its tank busting properties when properly shaped combined with a pyrophoric tendency provides added lethality. Risks to soldiers from uranium smoke particles is controversial.

--
Regards,
Martin Brown

On a sunny day (Tue, 25 Oct 2011 15:38:49 -0500) it happened Jon Elson wrote in :

drinks.

bones in a lead box...

Long time ago I got a job through an agency .. electronics, my first assignment was to calibrate radiation detectors. I had no clue (tm) and asked 'with what shall I calibrate this?' Well, the radioactive source was laying in the window, I looked, was shocked, and walked to the manager and told him I was leaving. Years later I was there again, different department, now for a much longer time. Many years later, about 4 years after I left, I did read in the paper that that whole place was contaminated. They were very easy about radiation, a bit too easy.

On a sunny day (Tue, 25 Oct 2011 15:30:16 -0500) it happened Jon Elson wrote in :

Yes, thank you for the informative reply. I think more than hundreds, actually, but was not so much looking at counts, but at the huge spike appearing in the spectrogram. Like I said before, auto scaling pushed all the rest down. As it was not calibrated for energy at that moment I cannot tell you what isotope it was.

On a sunny day (Tue, 25 Oct 2011 13:18:16 -0700) it happened snipped-for-privacy@radagast.org (Dave Platt) wrote in :

But I do not, but if the US keeps acting this way how else should I see them?

I was reading about their new secretary of defence, I think he is called 'panetta' or something., I wondered what 'panetta' could mean, and came up with pancakes and vendetta. He is Italian, but maybe he changed the pizza for pancakes, and vendetta against the rest of the world. I am still evaluating his brain patterns, but I think he is re-evaluating the 'first [nuclear] strike'. The common idea is that it does not pay, as the nuclear response would do too much damage. So he and the Omama together are a trigger [button] happy due, I think he is darkness with a facade of grins and jokes ... this duo may do a first nuclear strike. I have always stated Obamama is a button pusher. We will see. Iran? N Korea? possible. Russia? He would be mad, but there is no evidence against that, China? Why?

He now states NATO should stay in Libia. Changing NATO from a defence system to protect Europe he makes it into an occupying force that neither has the support of the majority of the locals there, now from the majority of the people in the countries that make up NATO. So, in that, NATO loses any divine purpose [if it had any], and becomes part of the circle of darkness surrounding more and more the US. I, personally am for a nuclear European force, and away with this new NATO. And Germany, France, Netherlands, Belgium, Spain, and all the Euro countries should participate in that force. Not the UK, Cameron does not like EU it seems, so he can side with the US. I would strongly urge the creation of a strong European army, nuclear army. After double agent Sarcasm eh Sarkozy or whatever is replaced by a more the Gaulle like leader.. OK, will see where it goes. Not may data points yet, not a very open book that pancake, difficult to read his mind, unlike GW Bush who was an open book.

Time, tick tick tick

BTW transistors usually have 3 legs, just to bring it back to the newsgroup charter if there is any. hehe :-)

against the rest of the world.

'first [nuclear] strike'.

much damage.

first nuclear strike.

occupying force

majority of the people

Checked out who pays for NATO recently? If you folks over there kept your commitments, you'd have a lot more say.

Cheers

Phil Hobbs

On a sunny day (Wed, 26 Oct 2011 10:36:13 -0400) it happened Phil Hobbs wrote in :

against the rest of the world.

'first [nuclear] strike'.

much damage.

first nuclear strike.

occupying force

the majority of the people

Say about what? US dictates NAVO. I want out.

US also dictates the UN. Everybode voted against the Cuba embargo today (for the nth time), except the US and Israel.

Good thing it got its rear end kicked on Syria by China and Russia. Sticks tongue out :-)

You really are in fine company if you are agreeing with China and Russia - 2 governments known for their altruism... Do you ever ask yourself 'Why'?

governments known for their altruism... Do you ever ask yourself 'Why'?

Well, China is open to helping out Europe in their hour of need, it turns out. Probably with the very same altruistic motives that the US had with the Marshall plan (and much the same end result).

Best regards, Spehro Pefhany

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On a sunny day (Wed, 26 Oct 2011 13:43:33 -0700 (PDT)) it happened snipped-for-privacy@gmail.com wrote in :

governments known for their altruism... Do you ever

Because those countries are not so braindead as to buy 350 dollar Flukes when a

3 dollar 49 cents multimeter will do, and their technicians know how to add a fuse if it was ever needed for use by a braindead american?