View Full Version : calculator radio waves
gold24h
05-06-2012, 01:21 AM
I was just curious if a scientific calculater like on the rangertell could actually be emitting radio waves,in fact it does,i found an fcc warning on a hewett packard scientific calculater,it said this device emitts raido waves but below the limit allowed,it also said it could interfere with tv and othere raido,so there may really be something to this rangertell.Also i found a chat on a forum about taking a calculater and an am radio and making a metal detecter,supposably the calculater sends out signals that the radio picks up.
Dave J.
05-06-2012, 03:40 AM
All active electrical devices (including thunderstorms, electric shavers, and the human brain) radiate electromagnetic energy.
Over on "that other LRL forum", arguments occasionally break out over whether pocket calculators radiate energy, and if so, how far. I usually stay out of that one because yes they do radiate energy, and "how far" depends on what kind of radio receiving apparatus you've got. All of that misses the point of course: if you swap the calculator for a CB radio with 1 watt output capable of being received at 10 miles with an ordinary receiver, that wouldn't make it any better a "treasure finder" than gluing a dried toad to the swivelly thingy instead.
Right now I've got a little electronic gizmo in my pocket which can locate my car from a distance of several hundred feet even in the dark, and doesn't get it confused with other cars. It's a long distance locator that actually works, it's not faked with a swivelly thingy, and it's designed by people who actually know what the heck they're doing. And for some reason, nobody wants to argue that the thing is just a fraud.
Obviously it ain't no Ranger-Tell.
--Dave J.
Qiaozhi
05-06-2012, 11:00 AM
... that wouldn't make it any better a "treasure finder" than gluing a dried toad to the swivelly thingy instead.
I like that dried toad analogy. :cool:
Dave J.
05-06-2012, 08:01 PM
[As I pointed out on "that other LRL forum"], if you remove the calculator and replace it with a cellphone, you've now got a far superior product-- the "Ranger-Tellyfone". You just dial the phone number of the target you want located. And, if that target is another cellphone, it really works, even in double-blind testing!
If it's a high-end cellphone, you've even got GPS and compass bearings and Google! Useful stuff for treasure hunting. The Ranger-Tell is not merely obsolete, it's downright Neanderthal.
--Dave J.
J_Player
05-10-2012, 03:54 PM
I was just curious if a scientific calculater like on the rangertell could actually be emitting radio waves,in fact it does,i found an fcc warning on a hewett packard scientific calculater,it said this device emitts raido waves but below the limit allowed,it also said it could interfere with tv and othere raido,so there may really be something to this rangertell.Also i found a chat on a forum about taking a calculater and an am radio and making a metal detecter,supposably the calculater sends out signals that the radio picks up.
Over on "that other LRL forum", arguments occasionally break out over whether pocket calculators radiate energy, and if so, how far. I usually stay out of that one because yes they do radiate energy, and "how far" depends on what kind of radio receiving apparatus you've got. All of that misses the point of course: if you swap the calculator for a CB radio with 1 watt output capable of being received at 10 miles with an ordinary receiver, that wouldn't make it any better a "treasure finder" than gluing a dried toad to the swivelly thingy instead. Hi gold24h and Dave,
Yes the calculator found on the Examiner does send out radio waves. These radio waves originate because the calculator has an internal clock which operates in the audio range usually below a few kilohertz as the highest clock divider. But the rising and falling edges of the clock signal can emit a small amount of noise at higher frequencies which are usually seen as random switching noise, and can be detected as broadband noise by nearby radio receivers or other sensitive electronic instruments. Dave is correct, it depends on what kind of receiving apparatus you have. Usually, radio receivers are designed to reject random noise, but at close distance, we see cheap radios are not immune. However, if you were to use a receiver that was designed to tune a known range of noise that comes from a calculator, you should be able to find a greater range than with a cheap pocket radio.
If you are planning to build a metal detector using a calculator and a pocket radio, then the range is limited by the ability of nearby metals to change the reception of this broadband noise. This has been seen to be about 2-5 inches in the examples that I have observed. If you wanted to make a metal detector with this concept, you may be better to build a small digital clock type oscillator that runs at a few KHz on a 9v battery. The voltage is important for producing longer range in broadband noise.
When you have apparatus that is not capable of tuning RF, then the distance which you can detect the noise from a calculator is much less. I did some test measurements on the calculators that come with an Examiner to see how far the calculator signals can be detected with a non-tuning pickup for magnetic and electric fields. I found that there is very little magnetic field detectable from calculator clocking noise, but the electric field can be detected up to about 6 inches distance before it becomes too weak to detect from among the background noise that is in the air. When you test the Examiner calculator using the same kind of spiral coil placed in the same position as the Examiner uses, you will find the signal strength shows about 1-2 mV on an oscilloscope for the higher clock frequencies, and it becomes smaller as you move the pickup coil farther away from the calculator. The larger voltages can be as high as 10mV, which are almost always lower frequencies which are envelopes that begin a pulse train to scan the keyboard.
I actually did a study on two different Examiner calculators. One was powered by two cells at 3v, while the other deluxe model used a TI solar calculator. It was surprising to see the deluxe solar calculator model produced a noticeably weaker signal, because it can only reach about 1.8v in the brightest sun. Even stranger, the clocking frequency is very much dependent on the brightness of the light that falls on the calculator. I watched the clocking frequency drop from 285 Hz in bright sun to 84 Hz in dark shady areas. During most sunny days it ran between 200-260Hz.
How any of this helps to find treasure, I haven't been able to figure out. In fact, I haven't seen anyone find treasure with an Examiner.
I have already posted a report showing some tests I ran on the earlier Examiner model T-G 808B here: http://www.longrangelocators.com/forums/showthread.php?p=117393#post11739
And now I am posting some additional testing I did for the Deluxe model with the TI solar calculator.
The solar calculator testing is much more revealing, and it shows some peculiar measurements that were not expected from these calculators or from the Examiner internal circuits.
See the ZIP files under the picture below. When you unzip the files, click on the html file to see the reports.
Best wishes, J_P
gold24h
05-13-2012, 02:16 AM
very interesting,i can not remember the whole post but there was some talk of measuring voltages on the rangertell while looking for targets,the voltage was suppose to go from o millivolts with no target to as high as 5 millivolts if picking up a targett,do you have any information about how to hook up the meter to do that.
Dave J.
05-13-2012, 03:14 AM
The Ranger-Tell doesn't detect targets. Therefore there is nothing to measure relating to target detection.
There are guys who don't understand how voltmeters work, observe readings of a few millivolts when they think the reading should be zero, and misinterpret what just happened. By doing so, and posting about it, they help maintain the LRL mystique.
--Dave J.
J_Player
05-13-2012, 04:39 AM
very interesting,i can not remember the whole post but there was some talk of measuring voltages on the rangertell while looking for targets,the voltage was suppose to go from o millivolts with no target to as high as 5 millivolts if picking up a targett,do you have any information about how to hook up the meter to do that.Hi gold24h,
I actually spent a lot of time testing for changes that happen when a target is placed within the claimed detection range.
What I discovered is that there is no change in the noise signals that can be measured on the Examiner antenna with my equipment when a gold, silver, or copper target is placed at different distances from the Examiner.
To understand how this testing was conducted, I made two types of tests:
In one case I started out in a test field which I first checked to insure there was no buried metal, then I would bury a gold, silver, or copper sample in one of several holes 2" deep that were spread out at various distances from the location where a volunteer held the Examiner.
After this testing was done, it was done again at the beach where no holes were used, and the samples were pushed under dry sand, then the test was repeated under wet sand.
The samples were a gold ring, a silver ring, and a 1/4 inch length of 1/2 inch copper pipe that looks like a ring.
The measuring was done with a Fluke 187 meter and an old Textronix 442 oscilloscope powered by an inverter connected to the car battery.
There was no measurable change in the noise signal measured on the Examiner antenna.
It did not matter what numbers were entered into the calculator.
The only change I could see was if the calculator was turned off, then the calculator clocking signal part of the noise disappeared.
After conducting these tests, it became apparent that there were problems related to interference with the noise signals we were measuring.
When a second person was walking in the test field near the Examiner, he could act as an electrical noise collector and influence the noise that you measure on the Examiner antenna.
We saw that the second person should not be moving near the examiner during the testing.
And we saw how the noise signal also changes as you walk around holding the Examiner.
In order to be able to watch a signal change as a target comes into range, we figured the best method would be to tie the target to the end of a fishing line and get an assistant who is standing far away from the test area to slowly move it closer to the examiner.
That is how the second class of tests were done.
As the rings were dragged from about 100 feet distance to the point where they touched the feet of the person holding the Examiner, we were able to detect no change in the noise signals on the Examiner antenna.
At the end of this test, we also tried dragging a 5-foot length of 2" diameter copper pipe past the examiner. -- Still no change in the noise signal seen as the pipe was dragged past the Examiner.
Later I made a lot of tests indoors moving targets tied to a string close to the examiner until they were within inches of the antenna.
Again, I could see no change in the signals I measured when the gold, silver, copper and various other materials were moved around the room.
When I saw that there was no change in the signals I measured, regardless of what key codes were entered into the calculator, I stopped making target tests, and started looking for other things that would change the signal measured.
All of the tests I made are repeatable by anyone who has an Examiner. You can try it yourself and see the same results that I saw.
If you find different results which show the signal changing when the target is near, I would be interested to know how I can duplicate your measurement to find the same detection signal as you find.
From what I have observed so far, it appears the Examiner does not detect anything except broadband airborne noise including the calculator clocking noise, which you can detect just as well with a coat hanger wire and a suitable instrument to observe the noise. I also have observed that nobody who tried to use the Examiners I tested was able to find hidden treasures with it.
Best wishes,
J_P
J_Player
05-13-2012, 05:57 AM
very interesting,i can not remember the whole post but there was some talk of measuring voltages on the rangertell while looking for targets,the voltage was suppose to go from o millivolts with no target to as high as 5 millivolts if picking up a targett,do you have any information about how to hook up the meter to do that.The measuring you are referring to is fake testing done by hung.
The readings you see are caused by using a cheap meter to measure tiny voltage signals while the test leads are dangling in the air, and you move your hands enough to cause capacitive charges to change the voltage readings at the meter.
Also note that there was no treasure shown during that test.
Hung said there is a "supposed gold target" because the Examiner pointed a particular direction after he pressed buttons for gold codes.
He never saw any gold.... he only supposes gold must be there.
The method to connect the meter was shown on the Rangertell web page.
Any electronic engineer knows better than to measure tiny voltages using a cheap meter with nothing grounded, dangling leads, and no shielding.
If you connect the meter in the same way, then you too will find many different millivolt signals.
But these have nothing to do with treasure being present.
The millivolts you measure will be noise you pick up from stray charges from the air, your body, nearby hardware, and possibly a meter offset error.
You should check with an electronic engineer who knows how to use a meter before you make the same mistakes that we see in the test.
You can read the original forum post here: http://www.longrangelocators.com/forums/showthread.php?t=13789
In that same thread you can check here to see what is wrong with the readings we are seeing:
www.longrangelocators.com/forums/showthread.php?p=63725#post63725 (http://www.longrangelocators.com/forums/showthread.php?p=63725#post63725)
...Then continue reading down.
You will see every electronic engineer agrees this is a bad test which is showing false information about treasure signals.
This is not the only time hung has submitted fake testing to help promote his favorite LRLs.
This test was posted several years before I made any measurements on Rangertell Examiners.
This fake test is part of the reason why I wanted to take some measurements to see what signals were really present in an Examiner.
What I observed was there is no change in the signal when treasure is nearby, and the calculator frequencies do not change no matter how many buttons you push.
But I measured how the examiner does pick up clocking noise signals from the calculator.
You will see that when we use good quality instruments which are properly grounded and shielded, these bogus voltages do not appear as a treasure is moved near to the examiner.
But there is a lot of air noise that can be measured at less than a few millivolts, coming mostly from power lines, man-made broadcasts, mobile phones, WIFI and computer frequencies, and of course, the calculator clocking.
This noise does not change when a treasure is introduced into the vicinity of the Examiner.
I have had an examiner available for anyone to test and see for themselves if it finds treasure or not. But so far, nobody is interested in trying.
All of the volunteers I have recruited failed to find any hidden treasure no matter what secret treasure numbers they put into the calculator, or how they adjusted the controls.
None of the owners of Examiners are willing to demonstrate their Examiner finding a treasure that you hide for them to find.
I know one treasure hunter who will be happy to sell you his Examiner in new condition because it does not find treasure for him.
From what I have seen, I do not think Examiner can find any treasure.
I advise anyone to try out a locator before spending money to buy one.
Make sure you are happy with the way it helps you to find treasure first, or don't buy it.
Best wishes,
J_P
Castrejon
05-20-2017, 08:11 AM
http://www.longrangelocators.com/forums/attachment.php?attachmentid=17956&stc=1&d=1336661520
That's a pretty big difference between the two. Thank you for testing them.
folharin
05-24-2017, 04:34 AM
you're right j_player!!
folharin
05-24-2017, 04:39 AM
Have some news rangertell???
folharin
05-24-2017, 04:42 AM
Are you lying to whom you cant,rangertell??
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