Attention Examiner users

[Mike(Mont)]

Carl, to start with you say the calculator does nothing and there is no induction.

[Carl-NC]

Carl, to start with you say the calculator does nothing and there is no induction.

True, I do state that there can be no induction -- not because the calculator doesn't produce a potential signal (I even state that it does), but rather:

The web site goes on to claim that the calculator couples to the circuitry inside the black box via induction, with the meandering piece of wire as the primary side of the "transformer". But this piece of wire is not connected to anything, and therefore is not part of any closed circuit, and cannot possibly support inductive coupling.

Mike, do you agree or disagree that a disconnected piece of wire cannot support inductive coupling? Or do you just not know?

If there is no inductive coupling, then the claims made about the calculator being able to "program" the other circuitry is false, and therefore the calculator does nothing useful.

My report is accurate on these points. Any other errors?

- Carl

[hung]

Mike, do you agree or disagree that a disconnected piece of wire cannot support inductive coupling? Or do you just not know?

Whaaat?
Well I'm not Mike, but in this question:... Is the wire bent or straight?.. Lies your answer.

If there is no inductive coupling, then the claims made about the calculator being able to "program" the other circuitry is false, and therefore the calculator does nothing useful.

My report is accurate on these points. Any other errors?

- Carl

With all respect to you Carl, with the inteligence and reputation you have, you could do better than that.
I don't know about Mike, but I don't need to answer this to you.

Regards.

[Carl-NC]

I thought this was interesting. It uses a calculator to provide a signal.

http://www.geekarmy.com/cool/Homemad...-Detector.html

The video either shows some interaction between the calculator and the AM radio caused by EMI or, as joecoin says, the guy is "... manipulating the volume with his thumb ...".

Does anyone here have a small AM radio to hand? This would be a very simple experiment to try.

This little experiment does work, and has been around at least since the 1960's. In my "vintage" detector collection, I have a "Ross" from the 70's, which is literally an AM radio, slightly modified with a search coil. There have been several BFO magazine projects which have a simple Colpitts oscillator for the TX, and an AM radio for the RX.

This experiment works best if either the oscillator is easy to shift (like a Colpitts), or the receiver (like a poor AM radio design). A calculator uses a crystal oscillator so it's not going to shift, therefore you need a cheesy AM radio to get a decent BFO operation. But sure, it will work. Distances are on the order of an inch or less.

I own a Radio Shack AM radio ("Flavoradio"), which happens to be identical to the AM radio stuffed inside the Treasure Scope Raven LRL.
This is one of the last AM-only radio designs and uses a pretty stable AM radio-on-a-chip, so it does not make for a good BFO when used with a calculator. But it will still "beat" with the calculator and produce a buzz. When you move a metal target nearby, the volume (not frequency) of the buzz decreases, because the metal is stealing induction energy from the radio. So it works more like an off-resonance design.

Now for the funny part...

"What calculator did you use, Carl?"

Well, since you asked, I used the Karce calculator from my Ranger-Tell Examiner. It has an all-plastic case, so the RFI leaks out unimpeded and the experiment works as I described.

But wait... I have a second Examiner, which uses the HP-6S calculator. This calculator has an all-metal case: solid on the back, and with lots of holes on the front for the buttons and display. With the front of the HP facing the AM radio, the holes for the buttons leak enough RFI for the experiment to work.

"But Carl, what happens when the HP's solid metal back is facing the AM radio, the way it faces the "induction circuitry" inside the Examiner?"

Good question! Nothing happens. The metal back blocks the RFI, and the experiment fails.

So, if you're still inclined to believe the Examiner's calculator couples a signal into the internal circuitry, it is probably worth pointing out the stupidity of using a calculator with a metal case that blocks that very "signal".

- Carl

[Carl-NC]

Well I'm not Mike, but in this question:... Is the wire bent or straight?.. Lies your answer.

I'll let you explain what difference that makes.

"My report is accurate on these points. Any other errors?"

I don't know about Mike, but I don't need to answer this to you.

No problem. If you can't point out any errors, then I'll accept that.

- Carl

[hung]

The metal back blocks the RFI, and the experiment fails.

Regarding the Examiner, it makes no difference if the calculator's back is made of metal or not.
It's the magnetic component which has to pass and this, not even a Faraday Cage will block.

[Carl-NC]

Regarding the Examiner, it makes no difference if the calculator's back is made of metal or not.
It's the magnetic component which has to pass and this, not even a Faraday Cage will block.

Are you saying that the "signal" from the calculator is actually a static magnetic field. Really? Seriously?

And, again, why does the disconnected wire need to be twisty?

I can't make this stuff up...

- Carl

[Qiaozhi]

This little experiment does work, and has been around at least since the 1960's. In my "vintage" detector collection, I have a "Ross" from the 70's, which is literally an AM radio, slightly modified with a search coil. There have been several BFO magazine projects which have a simple Colpitts oscillator for the TX, and an AM radio for the RX.

Yes - that's ye simple olde idea for a metal detector.
However, I was wondering how this could be the same principle as the calculator-based detector shown in the video, even though the rate of beeping changed.

This is one of the last AM-only radio designs and uses a pretty stable AM radio-on-a-chip, so it does not make for a good BFO when used with a calculator. But it will still "beat" with the calculator and produce a buzz. When you move a metal target nearby, the volume (not frequency) of the buzz decreases, because the metal is stealing induction energy from the radio. So it works more like an off-resonance design.

Personally I didn't think the video was a fake, as this same project is mentioned in the book "Sneakier Uses For Everyday Things".
Anyway, it's good that you can confirm its authenticity.

[Mike(Mont)]

Yes, we could get into an argument about what "the calculator does nothing useful" means or how induction works on a disconnected wire (think of a chain of paperclips near a magnet), but since it was under the heading of "The Truth" most people would assume the author to be some kind of authority on LRL's. It's always been my opinion a non-golfer does not make a good golf club tester. I also suggest Carl do some more homework on force fields. The ranger-tell website has a diagram on the "How it works" page.

I understand some people cannot learn how to use a locator rod. Maybe they expect too much. Hold a neodymium magnet out at arms length (north seeking pole facing away), close your eyes and turn around and try to feel where north is. Like with all rod work, be casual, be cool but be ready/aware.

[Carl-NC]

Yes, we could get into an argument about what "the calculator does nothing useful" means or how induction works on a disconnected wire (think of a chain of paperclips near a magnet)...

Mike, do you understand that the attraction a static magnetic field has on paper clips is not an example of induction?

Do you understand that the oscillator in a calculator produces an alternating electromagnetic field, not a static magnetic field?

Do you understand that a disconnected piece of wire cannot possibly form part of an induction transformer?

These are not minor nuances we can disagree about, these are very fundamental concepts that are well-known and well-understood by science. If you don't understand these, then taking the time to learn about them will be far more rewarding than simply saying everyone else has to be wrong.

The ranger-tell website has a diagram on the "How it works" page.

Which is completely made-up, and completely laughable.

I'll ask again: Can you point out any errors in my report? Hung couldn't.

- Carl

[Mike(Mont)]

I'm not saying this is exact, but the diagram attempts to explain the fields involved. Howard Johnson's magnetics studies might give you some insight.

http://www.rangertell.com/fieldfx.htm

[Carl-NC]

I'm not saying this is exact, but the diagram attempts to explain the fields involved. http://www.rangertell.com/fieldfx.htm

Mike, do you understand that this is all made-up? Fabricated? Fake? Concocted? Pretend? Make-believe? Bogus?

Howard Johnson's magnetics studies might give you some insight.

Do you understand that trying to prove pseudoscience with other pseudoscience doesn't work, either?

Can you point out any errors in my report? If you can't do it, just say, "I can't do it."

- Carl

[Fred]

Mike,i have followed your link, it is really filled with BS.
You are making yourself ridiculous by trying ti defend such "explanations"
A least i found one phrase funny.I resumes the whole page:
"When asked whether electrical energy flowed form (+) to (-) or (–) to (+), he determined that electrical energy flowed both ways. The only difference was the polarity."

Fred.

[Qiaozhi]

I'm not saying this is exact, but the diagram attempts to explain the fields involved. Howard Johnson's magnetics studies might give you some insight.
http://www.rangertell.com/fieldfx.htm

Howard Johnson is the man who believes he can build a permanent magnet motor, which is essentially a perpetual motion machine. I do not think examining HJ's magnetics studies will provide the remotest insight into anything useful, or (in fact) anything non-useful, like a placing a cheap calculator next to a disconnected piece of wire.

[hung]

Can you point out any errors in my report? Hung couldn't.

- Carl

Of course I couldn't. I was out of town. But now I can.