proposal

No idea.

John Larkin has a high opinion of the value of his doodles.

If you look at the output from a zener diode on an oscilloscope, it appears to made up of jumps between discrete levels; although it may be time-random it isn't voltage-random.

For a rough-and-ready audio noise generator, I used the noise of the blue LED pilot light and amplified it with a quad op-amp. i also included a state-variable filter so you could select:

Full bandwidth High pass Low pass Narrow peak Narrow notch

I never said that. I did a quick experiment and put in in my notebook. There was a region where it definitely oscillated. I learned things.

I have a prettier note about GHz range noise from a BFT25 b-e junction zenering. Bad for beta, of course.

Post some of your doodles.

John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics

I posted some notes on that. I found different behavior in different current zones.

Was the led forward biased? What was its noise amplitude?

The nice thing about zener noise is that it's big, so swamps amplifier noise, like 1/f.

John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics

It’s also highly asymmetrical and often has a peaky spectrum, especially at lower currents iirc.

Folk have tried fixing the symmetry by putting two in series and coming out the midpoint. That makes it better, but to get decent (not cryptographic quality) noise, AIUI you have to run the zeners at fairly high bias and filter the output.

Cheers

Phil Hobbs

XORing the outputs of two or more mediocre uncorrelated noise generators vastly improves the final result. John

I just had an idea foe a random noise generator. Using a PMT or other radiation detector you need 3 tics only, this gives you 2 time spaces say t1 and t2

tick1 t1 tick2 t2 tick3

Now write the ratio t2 / t1 as your random number.

As pr2cise as you can measure time, say nano seconds

It is the old alien crypto secret (from sci.crypt decennia ago) Alien comes to earth and wants to keep all he learned here back with him in his small flying saucer. Has a weight and size problem fitting it all in.

So gets the encyclopedia Britannica and writes it out as ASCII numbers does 1 / that number, He then takes a tick and sets a marker on his stick where the ratio is. Then takes the stick with him.

What I am saying is: All you need to encode and then later decode is 3 points in time. The ratio of those areas / times formed by those 3 points tells you everything. That is why I can hear from ticks by somebody on the table what his brain is thinking. Same for the the sounds in speech.

But from the 3 radiation pulses not much _human knowledge_ is transferred, as such 'random'.

Simple. xor you data with that number

Or you can xor you data with Pi (the 3. something number) do not tell anyone.

Dear Jan,

Are you talking about creating random noise via Geiger [1] counters? Now I don't recall if this was something I read, or thought up inde- pendently, so please assume this is part of the random noise literature.

One idea is to take the audio input [as output from the counter] and sample at fixed intervals. By pointing the detector at something radio- active, your nearest coal mine comes to mind, you should get a fairly decent random sample of noise vs. silence.

I have decided to cross post to sci.energy.atomic, and hope the nearest three letter agency can fill us in on the details of this operation.

I'm sure there are other ways to take standardized Geiger counters, and apply their use for random noise generation. What do you think?

Yes, it was used as the pilot light.

The total voltage gain was about 10^5 to give a 0dBm output, so the noise was around -100dBu.

,-""""-. ,-'""`-. ,-'""`-. / \ ; : ; : :(_) (_); : : : : ` '` ' : _ _ ; : (_) (_) ; `++++' : ( ) ( ) : ` '` ' `--' :: '` :; :`++++'; /mv/ !: :! ``..'' `:`++++';' `....'

------------------------------------------------ Thank you for visiting https://asciiart.website/This ASCII pic can be found at https://asciiart.website/art/3699

Sadly, I do not have electronic designs ready, but you can have some of my old A.S.C.I.I. art as a thank you for your doodle.

Best wishes, and happy doodles!

People sell noise diodes, zeners with guaranteed spectral behavior.

You might have learned much the same thing from the ancient thread where Win Hill, Tony Williams and I and a bunch of others speculated about zener diode oscillations. Some experiments were done - none by me.

They aren't remotely interesting. I do post LTSpice .asc files from time to time.

You might have learned much the same thing from the ancient thread where Win Hill, Tony Williams and I and a bunch of others speculated about zener diode oscillations. Some experiments were done - none by me.

They aren't remotely interesting. I do post LTSpice .asc files from time to time.

That should be -100dBm, surely?

Jeroen Belleman

I have a Geiger radiation counter running 24/7 here every minute the radiation (as number of 'ticks' per minute) is logged to a Raspberry Pi computer. When I moved house the average level (ticks per minute) went up!

To see WHAT radiates I also have a gamma spectrometer (bit bigger).

This is an other (to keep electronic design happy) radiation counter:

All battery powered as likely no power when the trump war house maniac starts throwing nukes in frustration if his polls drop to zero. (US politics cross posting required?)

Anyways, there is a radiation group too:

Every one should have a radiation counter these days, so simple. We had, in Europe, the Chernobyl disaster. The place where I worked in the Netherlands (far far far away from that reactor) had the airco filters replaced as those were 'hot'. 'Do not eat stuff from your garden" was the warning. mm breathing the air all day long outside??? That was long ago, am almost 80 now, maybe radiation is NOT that dangerous, but fear sells? Wildlife flourishes in Chernobyl, mainly because there are no humans there now to kill it. LOL I have worked with radiation at work too, was very afraid, left, later camw back in an other facility there. that place got completely polluted with radiation 2 years after I left there, they were careless. And now?

Build you own nuclear reactor? Is probably illegal. Fusion power will never work anyway!!! How stupid can they get? Einstone babblers. Getting carried away here a bit. But it must be pointed out!

So..

I have a Geiger radiation counter running 24/7 here every minute the radiation (as number of 'ticks' per minute) is logged to a Raspberry Pi computer. When I moved house the average level (ticks per minute) went up!

To see WHAT radiates I also have a gamma spectrometer (bit bigger).

This is an other (to keep electronic design happy) radiation counter:

All battery powered as likely no power when the trump war house maniac starts throwing nukes in frustration if his polls drop to zero. (US politics cross posting required?)

Anyways, there is a radiation group too:

Every one should have a radiation counter these days, so simple. We had, in Europe, the Chernobyl disaster. The place where I worked in the Netherlands (far far far away from that reactor) had the airco filters replaced as those were 'hot'. 'Do not eat stuff from your garden" was the warning. mm breathing the air all day long outside??? That was long ago, am almost 80 now, maybe radiation is NOT that dangerous, but fear sells? Wildlife flourishes in Chernobyl, mainly because there are no humans there now to kill it. LOL I have worked with radiation at work too, was very afraid, left, later camw back in an other facility there. that place got completely polluted with radiation 2 years after I left there, they were careless. And now?

Build you own nuclear reactor? Is probably illegal. Fusion power will never work anyway!!! How stupid can they get? Einstone babblers. Getting carried away here a bit. But it must be pointed out!

So..

It has been working for us for the last few billion years.

The sun is fusion reactor, fusing hydrogen into heavier elements.

It mostly runs on proton-fusion at the moment

Jan Panteltje may not be stupid, but he isn't all that well-informed.

No, that was the (near) open-circuit voltage but it wasn't delivering that voltage into a 600-ohm load, so that is no indication of the power (which is what dBm measures). A voltage level of -100 dBu would only be equivelent to -100dBm if the circuit impedance were 600 0hms.

Tekdoodles:

John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics