Eric Dollard

[Aaron]

Crystal Radio Initiative update

There was another error found in the Crystal Radio Initiative book. Pages 55-57 or so, there were scanned copies regarding coil self capacitance calculations. The scanned pages showed 451 and 453 but not 452. 452 now shows up in the pdf. Those pages were from the Radiotron Designers Handbook. Just go to the same download link as before.

Eric says those calculations are very accurate based on his experiments. Do not worry about wire diameter. The conductor should be as large as possible. He already gave formula for wire size.

[Nhopa]

Cri

Hi t-rex:

It is a honor to get feed back from you, thank you. My take on Tesla that he was overly concerned about the distributed capacity of his coils. Later around the 1920s other people got involved with the subject as shown by the two patent applications.
Yesterday I found some more info on the subject from 2001. All the equation used in the HAMCALC program. At one time this program was available free from the internet but it seems now disappeared.
One of the equations calculates out the distributed capacity of coils. The info needed for the calc. are:
L - coil length (in)
n - number of turn
W - wire diameter (in)
d - coil diameter (in)
Co - distributed capacity (pF)
Sw=L/n
Sd=Sw/W

Co=(Pixd/3.6)arccoshSd

I calculated my secondary coils Co and I got 22.29 pF versus my previous measurement and graphing that gave me 19.47 pF.
So regardless what Tesla was thinking at his time, it would be nice to eliminate this quantity from my experiment so that I would have one less thing to "worry " about.
I don't mind experimenting with my coil and to try to insert small capacitors in series with the turns. Perhaps four 5 pF capacitors that would give me an equivalent of 1.17 pF for the coil.
I ordered my copper grounding wire so once I get it I can finish my star diagonal ground system. For the telluric antenna I will have to buy insulated wire that is rated for outdoor underground service. The wire I used in the experiments is insulated but not for outdoor use. Do you have a suggestion as to what is a minimum gage wire I can use?

[t-rex]

coil self capacitance

Tesla was totally in the dark as far as the nature of self capacitance of coils. Do not get lost in his confusion. The self capacitance of a coil turns out to be primarily a function of the height to width ratio only. The number of turns or wire diameter has little to do with it.

Hi dR-Green and Sputins:
Thank you for your comments.
I need some help sorting out the issue of distributed capacity.
In Tesla's CSN on page 72 (on the top) it says that the distance between coil turns would have to be reduced to 1/83 of the previous value in order to reduce distributed capacity. This number came about because Tesla reduced the wire size from #10 to #31 in order to have a much smaller distributed capacity.
I found two US patents, 1342209 and1409352, both of which claims that their invention will reduce coil distributed capacity. One states that the distributed capacity effect is inversely proportional to the spacing between the turns. This seems to be contradicting Tesla's finding.
Let say we agree with these patent claims, can we benefit by winding our secondary coil in accordance with one of the methods?
For one of my secondary coil I calculated 19.47 pF (this value will be re verified) for the distributed capacity. According to Tesla one can place capacitors in series with the coil turns to reduce the distributed capacity. In my case how do I determine how many and what value capacitors should I use.
Eric gives the spacing between coil turn centers as Tau=l/N*2xPi, this equation does not take into consideration the magnitude of distributed capacity as a function of the coil turns spacing. Take care.

[Nhopa]

CRI and the distributed capacity

Hi dR-Green and Sputins:
Thank you for your comments.
I need some help sorting out the issue of distributed capacity.
In Tesla's CSN on page 72 (on the top) it says that the distance between coil turns would have to be reduced to 1/83 of the previous value in order to reduce distributed capacity. This number came about because Tesla reduced the wire size from #10 to #31 in order to have a much smaller distributed capacity.
I found two US patents, 1342209 and1409352, both of which claims that their invention will reduce coil distributed capacity. One states that the distributed capacity effect is inversely proportional to the spacing between the turns. This seems to be contradicting Tesla's finding.
Let say we agree with these patent claims, can we benefit by winding our secondary coil in accordance with one of the methods?
For one of my secondary coil I calculated 19.47 pF (this value will be re verified) for the distributed capacity. According to Tesla one can place capacitors in series with the coil turns to reduce the distributed capacity. In my case how do I determine how many and what value capacitors should I use.
Eric gives the spacing between coil turn centers as Tau=l/N*2xPi, this equation does not take into consideration the magnitude of distributed capacity as a function of the coil turns spacing. Take care.

[dR-Green]

Yes indeed, excellent work Nhopa!

[Nhopa]

Cri

Hi Sputins:

I am looking for volunteers to help me dig. I live just north of Phoenix, AZ.
But beside joking I am thinking on some additional testing before putting the wire underground. Since Erik and I were using insulated cable and wire respectively, what would happen if I use bare wire?
Your questions will be welcome and I may be able test some of your concerns or suggestions.
Before you do your star radial system, please read the reference I posted about a month ago. The title was "Designing for a Low Resistance Earth Interface - Rev. B-102407". It will save you money on the number of rods required, also it contains some neat calculations. I also have space limitation so my star radial consist of 5 rods, one in the center and 4 more on a 17' radius circle and the rods spaced 60 degrees apart. I have not yet wired the rods together because I still have to buy #6 or #8 copper wire. I am having problem with Eric wiring together all the grounding rods, because in my mind it defeats the purpose of a good ground. On the other hand if Eric wants to create a telluric antenna system, then may be that is the way to go but I do not think you can have it both ways. I may experiment with that set up after I properly wired the grounding rods.
If Eric is willing to do more testing then he could for instance quantify effective cable/wire length by measuring with instrument the increase of reception strength vs. conductor length and verify best take off point for the telluric signal.

[Sputins]

Hi Nhopa,
Some real good experimenting and discovery going on there.. I’ve really enjoyed viewing the pictures and reading about your findings. The desert surroundings and landscape (Coyote country) where you are looks fantastic.

There hasn’t been much reporting of such grounding experiments on the EPD forum (except from Eric himself), so keep going with it! Albeit hard work with the ground type you’re working with.

With further thought and results from your analysis, I’ll have some additional questions.

Around November or so I’ll hopefully be setting up my own star-radial grounding system, but I’ll completely different soil type and a smaller area to work with.

Great work sir.

[Nhopa]

CRI update III

Hi all:

Today I have done some more testing before burying the wires. I removed the small coil from the middle of the two 100 feet wires and then connected the wires together. First I moved the coil to the ungrounded end of the 200 feet long wire but the reception was not good. Next I moved the coil to the grounded end of the long wire and connected the other end of the coil to the grounding rod. The reception was very strong. Next I removed the small coil from the circuit and connected the 200 feet long wire directly to the grounding rod. The reception was just as good as with the small coil attached. For these tests the radio is tuned to a station that is barely audible then the radio is moved parallel to it's tuned position toward the grounding rod and when next to the grounding rod, the reception was very loud. I ran the radio dial from end to end and lots of stations came in very loud.
Finally I moved a one end of the 100 feet long wire next to my unfinished star radial grounding system, connected the small coil between the wire and the grounding rod but the radio reception was not to great. Next I connected the other 100 feet long wire to the end of the first but perpendicular to it and the reception was again great. With this arrangement the wires are running along two sides of my garden wall and this way I could add another 100 feet long wire to the end, making the total length 300 feet.
I don't know if Eric still reads the forum posts but if he is willing to verify my findings that would be great. In that case two things need to be done.
First, disconnect the two 6000 feet cables and move the small coil between the grounding rod and the 6000 feet long cable and check the AM reception, then remove the coil and just connect the cable end to the grounding wire and again check the reception.
Second, connect the second 6000 feet long cable to the first length and see if the AM reception improves with 12,000 feet long cable compared to the single 6000 feet run.
It would be nice to know if there is a practical limit to the length of the buried cable, perhaps related to the longest wave length we wish to utilize?
Also, if this telluric system so efficient then may be possible to use it for communication between Eric and ourselves (if this would not violate FCC rules).
At this point I am confident if I build this telluric system then my experimentation with Eric's CRI will bring good results.
As before, comments and suggestions are welcome.

[Nhopa]

CRI update II

Hi to all:
I did some more experimenting with the two 100 feet wire arrangement. First I ran each 100 feet segment by folding into two 50 feet length, parallel to each other, about 2 feet apart. The result was that the reception decreased by the amount the ground connection provided before. In other words I could disconnect the ground connection without any change in reception. Next I ran one of the 100 feet wire back and forth 10 feet lengths about 1 foot apart. Again I did not notice any different in reception but as before the ground had no contribution to the reception strength. Next I took one 100 feet wire and coiled it up to 22" diameter. The reception got much worst. Next I ran one of the 100 feet wires perpendicular to the other 100 feet and it seemed to work as the straight run does.
In conclusion the two equal length insulated wires laying on the ground in a straight run with one end connected to a grounding bar and in the middle they are connected to a small 2-3 turn coil of about 3" diameter work well similar to Eric's experiment. It also seems that the perpendicular wire orientation also works well.
Now the next step is to burry the wires and see the result. It seems to me that the increase in signal strength does come from the ground below the wires. I think the reason for the folded wires not performing as well as the straight run is the way the telluric waves intercept the wires. When folded the same wave front meets the wire multiple times and since the wire goes back and forth parallel to itself, the effect on each run cancels out the effect on the adjacent run. On the other hand, the straight wire runs meet a much larger telluric wave front thus the result is a strong increase in reception strength.
Comments and suggestions are welcome.

[Nhopa]

CRI update

Hi to all:
In the past week I did some experimentation by trying to duplicate Eric's telluric antenna system.
I laid down on the ground two 100 feet long insulated wire (1.2 mm dia.) in a straight line.
At the far ends of the wires I drove into the ground two 30 inch long grounding bars with quick connects.
In the middle of the two 100 feet wires I connected a 2 1/2 turn wire loop (2 mm dia.), loop dia. about 3 inches.
I have a not to sophisticated AM/FM radio.
First, the ends of the 100 feet wires were not connected to the grounding bars.
I took the radio and tuned it to a very weak AM station (rotating the radio until the audio was barely noticeable). Next I moved the radio next to the wire loop while keeping it's relative orientation the same. There were definite improvement in the audio strength.
Second, I connected the ends of the 100 feet wires to the grounding bars. The audio got noticeably louder.
Third, I removed one wire end from the grounding bar and the audio got even louder compared to the previous setting. It did not make any different at which wire end I made the disconnecti.
Conclusion so far is that having a long wire laying on the ground and split in the middle with a few turns coil added and one end connected to a grounding bar considerably improves the radio's AM reception, just as Eric demonstrated in his video. I will run one more test where I will run the two 100 feet wires parallel to each other 12, 24 and 36 inches apart to see if these make any difference in reception. This may demonstrate that "folding" the wires will accomplish the same as wires on a straight run.
Next step is to burry the wire. For this to happen I have to dig a 200 feet long trench in a very hard soil. The only way I can do this is to use my pick axe. I am shooting for at 6 inches depth but if my strength holds out I will go for 9 inches. The other problem is that the local temperature still hover around 100 degree F.
I thought I will be clever and name Eric's system a "grountenna", but before doing so I "googled" the word and to my surprise I found out that I was about 90 years to late. It appears that in 1925 a company "Western Coil and Electrical Co" was advertising a device called the "Radiodyne Grountenna"that was suppose to make the use of all outside "aerials" for radio reception obsolete.
This left me with the choice of the word "groundantenna" for which google showed no usage.
Your comments and suggestions are welcome.

[Nhopa]

Cri

Hi to all experimenters:

The point of the following discussion is to try to find out what do we need material wise to follow/duplicate Eric's experiments. Copper prices are very high, therefore, it is important to know what is the minimum usable size for a conductor for our experiments.

I have again carefully watched Eric's CRI video. He is using two 6000 feet long underground telephone cable for "antenna"? The two far ends of the 6000 feet cable runs are grounded, in the middle he connected a two loop coil to the ends of the 6000 feet cables. No information is given on the grounding rods' material, diameter or length. Eric is using the phone cable's metal shield only and not the multi conductor wire bundle inside. I have a large length of old Radio Shack phone cable, part no. 276-776, that has 25 individual insulated #28 gage multi strand wires inside that are wrapped with aluminum foil and covered with a braided metal shield and covered with insulation. So basically we have two 6000 feet insulated single conductors that are grounded at the opposite ends. It would be nice and very educational if Eric would run some tests with two 3000 feet cables, then with two 1000 feet cables and two 500 feet cables and finally with two 100 feet cables, and tabulate the results in terms of AM reception strength vs. underground antenna length.

In the video Eric mentions the cable depth as between 18" and 36". At this point I think as long the cable is buried even just 6" it will work fine. The radio waves bouncing back and forth inside the earth will intercept the cables regardless the buried depth. I would like to see a picture from Eric that shows his concept of radio waves' propagation inside the earth.
The volume of the metal shields inside the phone cable is considerable. I don't know Eric's cable diameter but my cable's foil and the braided metal shield probably equivalent to at least a #4 solid conductor.

[dR-Green]

The new and improved demonstration video has landed. There have also been content changes; different waveforms and octaves have been added, and the sawtooth waveform demo of scales was removed. Also the notes are now displayed on the screen along with the frequency analyser, oscilloscope displaying waveform, and oscilloscope displaying phase angles.

Video position description:

Introducing the concept of dissonance
0:00-1:24 - Sawtooth waveform
1:24-2:56 - Sine waveform

Scales - Sine waveform
2:56-3:17 - Equal temperament C4 + F4 + F3 + Octaves
3:17-3:38 - Pythagorean C4 + F4 + F3 + Octaves
3:38-3:58 - Equal temperament C4 + G4 + G3 + Octaves
3:58-4:20 - Pythagorean C4 + G4 + G3 + Octaves
4:20-5:02 - Alternations

Scales - Square waveform + distortion (harmonic emphasis)
5:02-5:25 - Equal temperament C4 + F4 + F3 + Octaves
5:25-5:45 - Pythagorean C4 + F4 + F3 + Octaves
5:45-6:05 - Equal temperament C4 + G4 + G3 + Octaves
6:05-6:28 - Pythagorean C4 + G4 + G3 + Octaves
6:28-7:21 - Alternations

Scales - Organ
7:21-7:43 - Equal temperament C4 + F4 + F3 + Octaves
7:43-8:04 - Pythagorean C4 + F4 + F3 + Octaves
8:04-8:25 - Equal temperament C4 + G4 + G3 + Octaves
8:25-8:46 - Pythagorean C4 + G4 + G3 + Octaves
8:46-9:24 - Alternations

Dissonance, Equal Temperament, And Pythagorean Scales - YouTube

Notes: The oscilloscopes are showing the clean square waveform with no distortion.
The spectrum analyser is on the output bus so the distorted square signal IS going through it so it's displaying all the harmonics, not the clean square waveform spectrum.

[dR-Green]

You might experiment with Pythagorean temperament ideas with you own music production?

I have stood in front of my friends’ invention / device which consists of ten pairs of speakers, (twenty in total). Each pair of speakers has its own amplifier and each amplifier is driven with its own discrete frequency all controlled from a PC and certain software. All of the frequencies are derived and based around the golden ratio. The reason for so many speakers is because one speaker could not physically reproduce the complexity of the sound. Standing in front and listening to this device for a time really moves you. There are nodes of sound that can be found by moving around in the space between them. It becomes a little addictive, seems to have strange effects on ones’ consciousness etc.

My friend is also a fan of Eric and his work, so I’m sure he might try and develop sounds with his device based on Pythagorean temperament.

Yes it could be interesting in a lot of ways. That's an interesting sounding contraption. I suppose the nodes on that might be most interesting. The bass is always strongest on the opposite side of my room because of the size of the room and the wavelength etc, with equal temperament this and the harmonics would be moving around as different components move in and out of phase, but with the Pythagorean tuning there will be definite points where such things converge. We can see in this way how music can be written for a particular room, which won't sound good when played elsewhere. I suppose that's one of the problems the audio engineer tries to overcome already (making it consistently sound good outside the studio), but it could take it to another level if the room it's played in is designed or incorporated into the music as an instrument in the performance.

[dR-Green]

Hi dR-Green:

I had a chance to watch the Eric's CRI video twice. A couple of thoughts:

1. Had Eric told us at the beginning not to worry about the extra coil and the importance of a very good grounding/ground antenna system under the experimental set up we would now have more people involved in the CRI with good results. I for one will start my experimentation again with the CRI based on the new instructions.

2. Once the lighting of a small bulb is achieved then we are ready for the experimentation with the extra coil.

3. In the video demonstrating the 12,000 feet long underground antenna's effect on AM radio reception it seemed to me that the underground telephone wire's orientation was not important and I also gathered that the wires were insulated and grounded on both ends. The reception with this set up was fantastic.

4. What is the significance of two 6,000 feet long wire? Just as a curiosity, what would be the reception with the same AM receiver if a 12,000 feet long above ground antenna is connected to it.


5. How the effectiveness of this telluric antenna changes with buried depth. Is there any data for that? I know Eric gives a range of depth in the video but it is not clear if the numbers are "out of the air" or based on some actual measurements.

6. Is it necessary for the in ground antenna to be a 12,000 feet long straight line? What would be the result if this 12,000 feet wire is laid out in a zig-zag fashion with a coupling coil in the middle of it. That is 100 feet lengths back and forth 60 times then the coupling coil and then again 100 feet lengths 60 times with grounding rods at both ends.

7. Can the superiority of the underground antenna be demonstrated with shorter length wires? What if the two shorter run is perpendicular to each other, that is at the end of one wire run the other wire run starts perpendicular to the first one?

8. The reason for the questions in paragraphs 6. and 7. are to possibly encourage an experimenter who does not have property with 12,000 feet straight runs to build a reduced size underground antenna system to experiment with.

Your observations about flowing water are very reveling and I can share your amazement. At one time in my life I was a white water raft guide on up to class V rivers and I am somewhat familiar with river hydraulics. I had the chance to observe how moving water creates formations that may be permanent or momentary and how the power of moving water created maybe a standing wave or a hole that is rotated upstream against the current. I also spent lots of time fly fishing in fast moving mountain streams and again an interested observer could see the endless formations that flowing water can display.

Sputins gave good answers but I'll add:

1. Someone had to build it to find out the extra coil was going to be too complicated/non-essential hindrance.

3, 4, 6. I think the 12,000 feet is just what happens to be there as a part of Eric's telluric system, or old telephone wire, I forget.

The main message I got from Eric for earthing for the TMT is that you don't want long continuous straight lines of wire because it causes stray inductance, so that's the reason for the zig-zag, to get rid of the unbroken long lines. Otherwise you want the arrangement to cover the greatest amount of area, to emulate a big sheet of metal in the ground through positioning the earth rods. In other words, a thousand earth rods crammed into a 10 metre diameter circle won't be much better than the 17 rod star radial, because it's the AREA that's covered by the arrangement. Which probably also relates to what you mentioned about the depth vs spacing ratio between each rod. Maybe that's because the same applies on the vertical axis as it does on the horizontal axis. [edit] On second thought, maybe not.

[Nhopa]

New CRI

Hi Sputins and all active members:

Thank you for the reply. The reason my previous e-mal was addressed to dR-Green is that it seemed to me he is the one who was back from "vacation" and always ready to respond. I hope beside you other members are reading the various posts. Anyone who is still participating in this forum should see Eric's CRI video and give it another try with the experiment.

Currently I am working on my new grounding system. I have five 8 feet long copper clad steel rods in the ground in a semi star radial fashion. One rod in the center and four more rods on a 17 feet radius semi circle placed 60 degree apart. Ordinarily I would connect the four rods to the center one with #6 bare copper wire and into the house also using #6 wire, But with Eric's recommended set up I could use #10 0r #12 bare copper wire except I need the depth. As deep as you can go is not good enough, here in the desert is not easy to dig a 6" wide x 24" deep (or deeper) trench between every rod or for a total of about 200 feet!

Also I am wondering if I connect every rod to every other rod as Eric shows it in the video do I reduce the systems effectiveness as a ground that is I kind of "short circuit" the grounding rods? I think I can experiment with my set up first properly connecting as my previously posted reference shows it and then add Eric's extra wires between all ground rods. It seems to me that what Eric is recommending is more of an underground antenna system than a ground.

I will keep you all posted on the progress.