Crystal Radio Magic

[jake]

Well it's not magic(sorry 4 the deception) but it is a radio, my first. It works and I can hear the one station I was hoping for; 1620kHz, 10,000 watts, 6 miles away.

I started this because of

Here is how the contest works. We learn how to make a "Crystal Set", just as everybody should. It is a "Rite of Passage". A crystal set is an A.M. radio that uses no battery, the magnification factor of its tank circuit powers the radio. Hence it can be seen that the A.M. broadcast station's transmitted energy is powering the crystal set, JUST AS TESLA ENVISIONED. Wow Mr. Wizard that is fantastic. Let's start today.
Break more to follow

Problem: It was easy, very easy. No matter what I do I can hear this station. I was expecting to have to "tune in" this station. So instead I minimized the components. An inductor(300uH, 60 turns, 20gauge), 1N34 germanium diode, crystal ear bud, and antenna(just about everything works(10 feet of 20 gauge, my body, cookie sheet, and even a beer can)) Some work better than others.
No capacitor??? Holding the coil is the best capacitor I found.
No ground. If I connect it to ground I either get a 60Hz hum when I use a water pipe or lower volume if I stick 2 feet of 6 gauge in the ground. I guess that means I need a better ground. Off to home depot for 10' water pipes.

Two questions for the group: (the goal is to maximize the reception of 1620kHz with only a crystal ear piece)

-There are a number of online calculators that allow you to calculate capatance for a given inductance or inductance for a given capatance, both for a given frequency? What "ratio" works best? (is it better to have more capatance or more inductance).

-Ground-What is good enough? Does it keep getting better as your ground system grows and gets deeper. Is it better to go deeper or wider(radial star like Dollard describes) I have lots of clay around here and I am going to try to water drill with the copper pipe as it goes down. How much better would 20' be over 10'?

Ok more than 2 questions but I'm learning.

[gyula]

Hi Jake,

Your biggest "problem" (may sound strange) is your closeness to the 10kW AM station... I mean the station makes too much field strength this is why almost anything behaves like an antenna, touching the coil makes big changes, etc.

First I would suggest using a coupling coil of 10-15 turns, placed to the bottom of your big air core coil, this coupling coil upper wire end would be connected to a 1 or 2m long wire (this latter serves as an antenna) and the lower end would go to Earth. Do not connect the big coil lower end to the coupling coil's earth point, ok?
Then you should find the capacitor needed for resonating your big coil to be a parallel LC circuit at 1620kHz. If you have now 300uH, then you would need 32.2pF to tune it to 1620kHz, the best would be to use a 40pF or 60pF trimmer capacitor. See link later for online LC calculator.
Then see this schematic here and I suggest making another 20-22 turn coil (not critical) onto your big air core coil, also to its bottom part, maybe over to the coupling coil mentioned above, this newer coil would serve as the L4 coil does in this schematic:
http://hibp.ecse.rpi.edu/~john/hi_power_xtal_set.gif
and you would need the diodes D1, D2, C3 and C4 of course, your crystal earpiece would connect to points A and B directly. (Do not connect this second coil to the earth point either.)

See this link where the schematics is referred to, it may be useful reading for you: High-Power Crystal Radio

I think your water tap earth is good enough but connect it ONLY to the antenna coupling coil I mentioned making first above, then you should not have 60Hz hum.

Another possibility is to use an AM ferrite antenna, like seen here:
Scotts Electronics Ferrite Loopstick Antenna Coil Crystal Radio Coils AM Coils but if you google you can find elsewhere too. Of course you do not have to make any antenna coupling coil for it, the Litze wire coil on the rod completes the antenna and if you choose the 680uh Litz wire coil with a tap at 470uh about 20 turns from end, then this 20 turn can serve as L4 for the diodes (you can separate the two wires which led out as a twisted wire to make the tap). This 680uH ferrite antenna needs 14pF capacitor across it.
I used this online calculator:
LC Resonance Calculator
(Notice the L value needs to be entered in nH, not in uH and f is in MHz.)

Normally it is better here to use higher L and lower C values but because of you want to receive a station at the very edge of the AM band the usual coils used for AM reception seems too high in value this is why so small pF value the tuning capacitor has (14pF or 32pF). You may wish to remove say 10-15 turns from your 60 turn air core coil to reduce its inductance and then increase the tuning cap higher or when using ferrite antenna the coil on the rod can be slided a bit off towards and / or beyond the rod's edge. The small cap values needed for 1620kHz resonance with such 300-680uH coils explain why you found good reception when you were holding the coil: your hand and body capacitance, your close presence to the coil supplied the 32pF tuning...

Hope this helps,

Gyula

[jake]

Extra thanks

That is exactly the kind of advice I was looking for. I appreciate it very much. I suffered information overload when I tried searching for the "ideal" capatance/inductance ratio. There are just so many ways to do it there does not seem to be an ideal way.

Im off to snip, tap, wind, and take off some turns.

Thanks,

[jake]

Whats the ground for?

I mean: I know what the ground is for but if you can receive a radio signal fine without a ground connection what additional benefit would you get if you attache to a good ground??

[gyula]

IF you can receive a station fine without ground connection, then I do not think you need ground for THAT station. I think it all depends on the sufficient field strength for a radio station at a particular location, a good ground can contribute to a much better reception (in a given receiving antenna case) when you wish to listen to a distant station which does not have a strong field 'presence' at your location.
What additional benefit? In your 6 miles away station case probably nothing (I have never had such chance lol), though you could probably use an even shorter piece of wire when you have a good ground. Remember the station transmitter antenna for the AM bands usually works against a big ground system and an isolated metal tower of a given vertical length is the radiator. So in a distant station case you can benefit from grounding because radiated station energy is taken also from the ground, not only from the 'air'.

Gyula

[dR-Green]

I mean: I know what the ground is for but if you can receive a radio signal fine without a ground connection what additional benefit would you get if you attache to a good ground??

A Tesla receiver won't work without the ground because it's designed to receive the underground signal. Herein lies the fallacy of so-called "wireless energy transmission"

[jake]

next generation crystal radio

So once I felt confortable with a typical crystal radio and could tune most of the stations on the high end of the AM band. I started to put together a Tesla Resonant Transformer. This is part of the crystal initative on the Dollard Thread.

Below are the results of three generations of coil formers. The former you see is stout and will allow you to pull the wire tight while winding. I am still missing the primary, topload, capacitors. BUT

It blows my crystal radio with tuning capacitor away. Attached are some pics. The DSO pic is my night time reception it came down from 1.3v earlier this afternoon with +4v peaks. This got me excited for a while but then I realized that my scope maxes out at 1MHz. Your looking at 1.62MHz rectified
audio. 100us/div and 50mv/div, the yellow line is 500mv.

Do these numbers mean anything or is working out of the range of my scope produce garbage numbrs???

And finally I was able to dimly light an LED in line with the germanium diode.

Any one know how to hook up a joule theif without loading down the circuit??

It looks like there is enought there to run one but doing it without loading down the circuit is eluding me.

[madhatter]

the primary coil is key to the ground receptive part of the set. the primary and secondary resonate and based on the capacitance and geometry the radiation resistance will be eliminated in the extra coil giving rise to FTL reception. On my set the primary is not large enough as I based it purely on surface area however after reading the reports of others and noting their relations and the effects between my set, I tentatively state that the surface area of winding capacitance is what needs to me matched, not the bulk surface area. I'm working on the equations to see what this turns up. I'm also looking at the skin effect and mass as well, no point in leaving any stone unturned.

Nice build btw, looks good. the extra coils is such a PITA to wind too. I wouldn't worry about 'skip' distance from being too close to the transmitter in fact I'd say that's a prime example of ground current reception, proof that this works.

[jake]

For example, the crystal set is a prime example of a information rich effects. I personally have the set built but have not gotten the results I want, however it's not been without results as it as given me answers to questions on capacitance by noting the differences in my results to others. however lets say we have one build that is catalog'd and every parameter of the physical construction known. from that it can be altered and the changes noted and then using that it can direct the mathematics to derive the needed equations to refine and move forward.

right now the one thing I've seen is the surface area and capacitance equations, capacitance is frustrating itself as it's always an assumed infinite plane yet we know it's not. high frequency skin effect and resistance of the mass of the 'director' and the geometry all play a role, as seen it gets very complex. I've spent a couple hundred hrs already on just calculations and have now just started to notice a few things I'd like to explore, with some more research into hyperbolic trig I may have some equations that can be tested in the field. I'll share this freely with anyone willing to test on their crystal sets. ultimately I'd like to see if we can all build matching sets and see if we can network them together as Tesla intended.

I am thinking the same thing. Matching sets would get noticed. Im thinking somewhere in the 2-3MHz range. That would make everything smaller and the brass shim stock would fit the bill. You could put that together for under 50 bucks. But we'd have to find a transmitter for the testing.

but before we get too far ahead of ourselves. We need to light an indicator bulb.


As far as my build. I am still looking for a long enough flat piece of copper.. I sent out a few emails looking for overruns, but the standard size seems to be 100" and I need 118". I found a thin walled copper tube at the scrap yard and bought enough.. Ive been contemplating slicing it open and flattening it out.

and now back to what I think was your point. The math needed to go along with the cyrstal initative. I want it. Been doing lots of thinking.

Lets start simple.. and I am really look forward to hearing from all those interested..

How do you calculate the C and K of a TRT secondary?
How do you calculate the L and M of a TRT secondary?
i.e. 20 turns(T), wire diameter(d) in mm, turn gap(g) in mm,

Can we even use the standard inductance and capacitance equations or are they contaminated? bring on the versors


Ill post my answer tomorrow? after I watch the SFTS videos If i can think of one.




jake

[madhatter]

I am thinking the same thing. Matching sets would get noticed. Im thinking somewhere in the 2-3MHz range. That would make everything smaller and the brass shim stock would fit the bill. You could put that together for under 50 bucks. But we'd have to find a transmitter for the testing.

but before we get too far ahead of ourselves. We need to light an indicator bulb.


As far as my build. I am still looking for a long enough flat piece of copper.. I sent out a few emails looking for overruns, but the standard size seems to be 100" and I need 118". I found a thin walled copper tube at the scrap yard and bought enough.. Ive been contemplating slicing it open and flattening it out.

and now back to what I think was your point. The math needed to go along with the cyrstal initative. I want it. Been doing lots of thinking.

Lets start simple.. and I am really look forward to hearing from all those interested..

How do you calculate the C and K of a TRT secondary?
How do you calculate the L and M of a TRT secondary?
i.e. 20 turns(T), wire diameter(d) in mm, turn gap(g) in mm,

Can we even use the standard inductance and capacitance equations or are they contaminated? bring on the versors


Ill post my answer tomorrow? after I watch the SFTS videos If i can think of one.




jake

Here is where hyperbolic algebra come in, Alexander Macfarlane has some very good books on hyperbolic and elliptical algebra. useful eq. for adapting to the coils can be found in Kennelys work as he does utilize Steinmetz and Heaviside's operators making it easier to cross reference his work.

the complex quantities notes of Steinmetz are also very helpful in explaining the j operator and power of the square root of -1.

[jake]

Here is where hyperbolic algebra come in, Alexander Macfarlane has some very good books on hyperbolic and elliptical algebra. useful eq. for adapting to the coils can be found in Kennelys work as he does utilize Steinmetz and Heaviside's operators making it easier to cross reference his work.

the complex quantities notes of Steinmetz are also very helpful in explaining the j operator and power of the square root of -1.

Thats where I am having trouble. I need to study.

So if all the adapting and math is down would it be able to calculate "values" for C,K,L,M and thier ratios at any point during the cycle of a TRT??? <---Please answer pretty please.. any one. What are the roadblocks?


That would help enormously in tuning the setup. It's almost impossible to tune three coils with 4 parameters that are changing without having either a solid math foundation or a natural ability to feel what you are doing. I'm working with the former at the moment. I'm not thinking about numbers; just C,K,M,L and what they are doing at every spot in the setup at every point in the cycle and and how I can add, reduce, and change their "rate".

Am I talking jibberish? or just a few months behind.
currently rewatching video 3 of the SFTS.



Also regarding the surface area aspect... Don't give up on mass just yet. Tesla's use of the word "stout" appears in lots of primaries.

My primary was calculated to 3m by 8.4cm by 0.1mm for a grand total of 26.4 cm^3.. Does that sound stout to you?

[madhatter]

Thats where I am having trouble. I need to study.

So if all the adapting and math is down would it be able to calculate "values" for C,K,L,M and thier ratios at any point during the cycle of a TRT??? <---Please answer pretty please.. any one. What are the roadblocks?

parametric changes are nearly impossible to calculate as they would occur on the fly and you'd need to run a simulator to get close. there is no program in existence that can do that for these parameters. you can get a rough layout that would need 'tuning' with the math and knowledge available at the moment.

Hyperbolic geometry is closer to nature, the cantenary slope is a prime example. a rope hung between two points exhibits this form. what also needs to be added into the equation is counter-space, due to the time invariant 'dimension' of the dielectric.

That would help enormously in tuning the setup. It's almost impossible to tune three coils with 4 parameters that are changing without having either a solid math foundation or a natural ability to feel what you are doing. I'm working with the former at the moment. I'm not thinking about numbers; just C,K,M,L and what they are doing at every spot in the setup at every point in the cycle and and how I can add, reduce, and change their "rate".

Am I talking jibberish? or just a few months behind.
currently rewatching video 3 of the SFTS.



Also regarding the surface area aspect... Don't give up on mass just yet. Tesla's use of the word "stout" appears in lots of primaries.

My primary was calculated to 3m by 8.4cm by 0.1mm for a grand total of 26.4 cm^3.. Does that sound stout to you?

I'm still researching every day, it's an undeveloped field. the majority of mathematics of manifolds and abstract algebra all conform to relativity, that makes it that much harder to develop a working set of equations as one needs to filter out the conforming terms and relations. it's mighty pervasive, one of the reasons why the bulk of reference material is pre-1927.

around the turn of the century there was a divide on quaternions as well, Alexander Macfarlane also postulated with hyperbolic quaternions and that can be seen in his lectures on the mathematics of space.

so an abstract non relativistic conforming algebraic hyperbolic counter-space geometry needs to be developed it would seem. a simple thing really

I don't abide by the reductionist view of quantum physics or a static state. we exist in a dynamic interconnected manifold, one change effects all. any equations that try to handle this will have a type of 'Heisenberg' uncertainty to use it loosely, it's ever changing and a static 'snapshot' will not explain the dynamic relations. personally I think true advancement will occur when apparatus become 'living' not sentient but more organic. loose terms there, but think of a plant vs a solar panel, the solar panel is rigidly fixed in it's parameters where the plant can adapt and change as needed constantly.

I've diverged enough there. To make any real gains a framework needs to be developed to model the manifold of the dielectric and then develop the basics of each phenomen, i.e. the e,E,I,i k K,c etc...

[jake]

Does anyone have tips for soldering 14ga solid to 1/2" copper pipe?

Do you wrap the wire around the pipe and solder all the way around or just solder ~1/2" however???

Still trying to calculate MKLC. Watching SFTS videos again this time taking notes.

@ mad

What do you mean by manifold?

[Parav]

Soldering Copper

Does anyone have tips for soldering 14ga solid to 1/2" copper pipe?

Do you wrap the wire around the pipe and solder all the way around or just solder ~1/2" however???

Still trying to calculate MKLC. Watching SFTS videos again this time taking notes.

@ mad

What do you mean by manifold?

Hi Jake,

To solder together thick pieces of solder , an ordinary soldering iron just does not provide enough heat as the heat gets dissipated into the thicker material too easily.
Use a propane torch -like what plumbers use to solder copper pipe fittings.
Also , make sure that the copper pipe is lightly sanded at the area you want to soldered -to get rid of the oxidization---or use that flux paste plumbers use to help clean off the oxidization while it's being soldered . Good luck--[I] hope this helps.

Paul

[Parav]

Hi Jake,

To solder together thick pieces of solder , an ordinary soldering iron just does not provide enough heat as the heat gets dissipated into the thicker material too easily.
Use a propane torch -like what plumbers use to solder copper pipe fittings.
Also , make sure that the copper pipe is lightly sanded at the area you want to soldered -to get rid of the oxidization---or use that flux paste plumbers use to help clean off the oxidization while it's being soldered . Good luck--[I] hope this helps.

Paul

oops typo-- I meant when soldering two pieces of thicker copper together