Spooky Tesla Spirit Radio

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Picture of Spooky Tesla Spirit Radio
News Flash!!!
The Spooky Tesla Spirit Radio and Mrfixitrick are now featured in a PC game called "Tesla".  Monsters and bats are battled, while helping Mrfixitrick find the seven parts of the Spooky Tesla Spirit Radio. Intriguing background music. From GODD Games at:

Have a look at the Crystal Quantum Radio devices of EJ Gold that helped inspire this instructable:

"My first observations positively terrified me as there was present in them something mysterious, not to say supernatural, and I was alone in my laboratory at night"
- Nikola Tesla, 1901 article "Talking With The Planets

The Spooky Tesla Spirit Radio is more than just a crystal radio circuit in a jam-jar. It's a sound maker that plugs in to a computer, and makes awesome spooky sounds by responding to electromagnetic fields or light sources in real time.

Athough Tesla used different parts, this radio's basic L-C (Inductor-Capacitor) circuit uses a similar schematic to what Tesla experimented with in his early days. The versatile 1N34A crystal germanium diode used here, substitutes for the tricky rotating nickel detectors and sensitive relays, used by Tesla in the late 1800's. 

You can listen to AM broadcasts with this radio, but it was made to have fun with in other ways. (Besides, AM radio wasn't exactly what Nikola Tesla was interested fact, he believed it was a waste of energy to transmit and receive Hertzian waves!) 

By using a program like Audio Hyjack Pro (Mac), the radio's output is tweaked at the computer to give some great real-time sound effects...and you can record them at the same time. 

In the following accompanying movies, I show how the Spooky Tesla Spirit Radio reacts to lightning, radio frequencies, the light spectrum, the computer screen, RF pulses, electromagnetic fields and more!

In the following video, the Spooky Tesla Spirit Radio is used to give voice to a Mac Hyperspace screensaver! The simple crystal circuit is apparently sensitive to the screen synchronization RF frequencies, and so it provides awesome background sounds...check it out:

The next movie shows "Spooky", the radio, beside a Dancing Ghost homopolar motor. The motor emits electromagnetic waves that are picked up by Spooky's antenna coils, and we hear the results translated through computer software in real time...spooky!!

Here's a movie of the action in the new PC game "Tesla", featuring the Spooky Tesla Spirit Radio;

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zwalker31 month ago

ive been having alot of trouble trying to get all of the parts here in canada. Is there a way i could pay you to ship them all too me? Also i remember reading somewhere that you would make one and ship it. how much would that cost? Ive got an experiment with some non-newtonian fluid and a tesla radio i would like to commence soon!

Canadian here. I was able to get most of the parts off ebay. The ferrite loopstick antenna, mono jacks and dials/knobs I got off a junk portable AM radio I got from goodwill. You can get a variable capacitor from the AM radio too but I just bought one from ebay with similar specs to what's in the instructable. I didn't find a reasonably priced crystal earpiece so I plan on making my own from piezo speakers I got from (you can find instructions from google). The copper wire for the antennas can be found at any hardware store. Hope this helps you and anyone not living in america.

msim934 years ago
 Pardon me, for it seems as if I'm asking a silly question.
I dont have the parts yet, but when it says "ground through the phone Plug" does that mean the negative of the computer phone jack?

Is that also where you would ground the C1 middle connection?

Like I said, it may be a silly/stupid question for me to ask. I'm still learning how to read schematics properly, and I just dont want to mess anything up.
mrfixitrick (author)  msim934 years ago
 You got it right on both accounts.

It seems that the negative of the computer phone jack works even better than a ground connection I made to a pipe in the ground.
Working on Aircraft My whole life. We always had to ground the airframe to the ground to remove static elecricity that can pop someone on the head and knock them out. That's when I started thinking about a Star Trek Stun Setting on their faser guns. I have seen guys knocked right out after walking under an area of an aircraft right after fight, A big PO on the head will knock you out cold. I think that would be better than teaser guns used by police. Maybe Someone could figure out how to use that kind of energy. Ya Think?? OH YEAH To ground air craft is to a copper rod about 12 feet long in the ground with just a couple inches high in a small hole on the ground. TAKES ALL THE SPARK AWAY. Ya Think??
Don't Feel ALONE, I'M AS CONFUSED AS ANYONE COULD BE. You are way in-front of my understanding. Some of the things you may call a silly question, are not silly at all because at least you know what the name of what you are asking about is, I Don't IF EVERYTHING WAS MECHANICAL I WOULD KNOW MOST ALL EVER NEEDED TO KNOW BUT THIS?? I'm not moving at all. I want to make it but I don't think I will be able to.
vger139 months ago
i am using a stereo cable i think that my be the problem,other than that i have tried hooking this thing up every way i can.right now it is connected like this one
mrfixitrick (author)  vger139 months ago
Try the mono cable and/or a longer antenna. You can also try hooking the two positive pins together on the stereo plug. To get stations, it pretty much requires a longer antenna. The short antenna is better for getting sounds from drills, motors, lights, etc.

vger139 months ago
ok ..i think something is grounded wrong,with patch cord plugged in i get nothing when i unplug and touch just the tip to the jack on the radio and touch tuning tip i get stations?
mrfixitrick (author)  vger139 months ago
Be sure the grounds are connected properly, and try my other suggestion of using a mono or stereo cable instead of the one you are using.

The antenna will likely have to be lengthened to 20 feet or so to get stations easily. Try the alternative antenna connections for long antenna, as seen in the schematic.
vger139 months ago
does it matter which side of the jack is ground?
mrfixitrick (author)  vger139 months ago
Try a mono plug and cord, or a stereo one if you already were using mono...that might make a difference. Also, try using a 20 foot or longer antenna to get a better signal, as it sounds like you are using your body successfully as one when you touch the tip!
vger139 months ago
no pc with audio mulch but your presets are no longer available ..goes to a cloud
mrfixitrick (author)  vger139 months ago
PC is more difficult, but here is an AudioMulch pre-set to try...
vger139 months ago
i have been trying this off and on since first posted,not sure what i am doing wrong but i get nothing other that static when hitting diode with laser ,used 100 mgains,.i dont see your unit grounded ..mabe it that the problem?
mrfixitrick (author)  vger139 months ago
Hi vger13,

If you hear static when you hit the diode with laser, you are on the right track. Now, the static has to be converted to an audible sound. Are you using Audio Hijack on a Mac with the "spooky radio" settings?
nerd74731 year ago
Dorkinator1 year ago
Thanks for the fast response, Rick.

I'm having touble posting this as a reply, so I just made a new post.

I will try out your suggestions tomorrow.

As for now, I have another question. Assuming we have the right circuit, should we be able to hear some kind of noise if we shine a green laser onto the diode.? Would we have to change the pf until we find the range its in, or should it detect it almost right away?

I appreciate the help, Mikey.
mrfixitrick (author)  Dorkinator1 year ago
The laser will be detected no matter what range. The problem is the gain has to be turned way up to hear the response, and the pitch has to be tuned to give a good solid sound. As before, you should be able to hear the audio plug loudly when touching the tip of it with your finger, before plugging it into the radio.

Good luck, let me know!
Dorkinator1 year ago
Hi, we are making this for my school project,really enjoying but because we are in Canada I had to use a variable capacitor from midnight science (365pf with 8:1 planetary gear) but which has 4 lugs. My questions are;
1) how to wire the variable capacitor, I believe we can use any of the 4 lugs then use a ground connection for the other side?
2) we are using a ferrite antenna from a am radio but which has 4 wires3, on 1 side and 1 on the other.
we are using audacity and so far its not working, I know I didnt fry the diode, any ideas would really help, many thanks, Mikey Pratte

You can email me at if you need to.
mrfixitrick (author)  Dorkinator1 year ago
Hi Mike,

The variable cap will likely be ok wiring as you describe. The ferrite antenna you will have to try various orientations of the wiring.

Start first by knowing that you get a very loud hum/noise when touching the end of the audio wire plug (with other end plugged into computer)

I found Audio Mulch worked better than Audacity on the PC.

I had to use 3 "Gain" modules to raise the volume enough.

Once you get a loud response, plug in the radio and put a source of EMF beside it, like a drill or motor or modem. You should begin to hear something.

For better reception, add a 20 foot antenna.

Let me know how that works for you!
Cheers, Rick
Thax1 year ago
I'm having real problems with my radio and I'm trying to understand the options you describe. I've built my radio as you've pictured yours, but I'm getting no signal or noise. I've checked all my parts and connections. "Run it direct with an antenna connection" doesn't help me understand. Can you clarify this? Thank you!
mrfixitrick (author)  Thax1 year ago
"Run it direct with an antenna connection" means when the induction coil does not have a 10-coil wire wrapped around it, and uses just the tiny wires of the induction coil in the circuit, as seen in inductor L1 and antenna Ant1 in the circuit diagram. The antenna Ant 2 and Ant 3 are auxiliary, and in some circumstances may work better.

For diagnosis, let's go back to basics first...
1.) Are you using a Mac with Audio Hijack, or what is your way of hearing the radio? Test: Do you get a very strong hum when you touch the end of the audio stereo plug on the wire that connects to the computer? If you don't, then the audio software or other adjustments must be made, as the radio needs tons of gain to be heard.
So, touching the end of the plug that goes into the radio, should sound very loud.

2.) If above test is ok, plug in the radio. Is there any sound at all? Turn up the volume if necessary. Touching the antenna should increase the sound.

Let me know, and we'll go from there!
I loaded Audio Hijack onto my Mac, but couldn't see how to make it open the windows you present. Then I loaded AudioMulch, which appeared much closer to 'right', but I still couldn't get anything out.
Better option, I thought, was to apply an Oscope to it and see if there was anything there. I found nothing but what I believe was that 60 cycle hum you mention. Phoey.
I hard wired the funny little 1970's earpiece that came with the crystal radio kit so I could more easily monitor if I made any change from further tweeks. In fact, your suggestion of removing the 10 coil seems to have some change. When I poke the variable cap a tiny burst of noise comes through the earpiece.
Still, this kit was supposed to be for kids, and it mocks me. I feel dumb.
mrfixitrick (author)  Thax1 year ago
Ok, what you likely need is lots more gain (assuming the radio is wired correctly and the diode was not overheated durting soldering ;)

Here's what to do: You need to set up Audio Hijack with my Spooky Tesla Spirit Radio Patch, which I just stored on Google Drive at this web address;

Go to the above address, and download the patch file there to your desktop. Then, open Audio Hijack, look at the top row and click on "Control" then select, "Import Effects Patch". In the window, find the patch on your desktop and open it. It should make Audio Hijack ready to go except for minor tweaking.

Note: You may need to set "Source Type" to "Audio Device". There should be 6 modules set up, AUBandpass, 10-Band EQ, 3 of AUPitch, and Reverb.  Be careful, as it could be very loud, turn down gain if necessary. 

The other thing that makes a huge difference in sound level is to attach a 20 or 22 foot long piece of wire to the antenna circuit and stretch it across the room. 
You should hear a sound increase by touching the antenna.

As a kid I spent hours messing with a chunk of germanium and a needle-like gizmo probe to finally get a station...and it would disappear the next day!  The crystal radio pros have big tuned coils and proper antennas. It becomes all about the tuning, selectivity and sensitivity at that level. 

Good luck, and let me know re: Audio Hijack. 
first, thank you for taking the time to work with me here. It is really a big help. I found a few mistakes I've made that have made a big help.
1: the output port I have has three leads. One ground, and two that appeared to be connected. I realized today that when the plug is in they disconnect and I had the circuit to the wrong lead. Fixed!
2: Audio Hijack is not the program I needed. Audio Hijack PRO provided what you've been describing that I couldn't find. Hallelujah! (on a side note, I used Pro for only a matter of minutes before it started piping in noise to get me to buy. grumble.)

So now I can hear a very deep low throbbing hum. Actually I get it even with just the patch cabe. Touching the antenna gets more static, better than nothing. I'm ready to attach a long antenna. Where in the circuit do i wire it to? Ground as the other seems to be? Or a separate floating 10 loop coil around the loopstick as it appears in the diagram? Or, as I find in another crystal radio circuit, on this unused third thread into the main antenna coil?
mrfixitrick (author)  Thax1 year ago
Glad to hear you are getting some results. That is the hum you are looking for, and the hum should be less with the patch cable connected to radio and computer. The free version of Audio Hijack PRO (hehe) will run for 10 minutes without static being added. Then just re-start the program. I liked Audio Hijack so much I gladly bought it.

As for antenna, I would wrap a 10-coil copper wire around the induction coil, and attach one end to "ground" or negative, and the other end to the long antenna. You may be wish to attach the antenna directly to that "third thread" wire instead of the 10-coil. Try each technique and see what sounds louder.

Especially with the antenna, if you are close to an AM radio station, you should be able to hear something when adjusting the variable cap. You might need to centre the "AUPitch" pitch controls to make sense of it.

Keep in mind, for the kind of fun I have with the radio, it's often best to tune outside of the main stations instead of on them. The AUPitch and other modules are used for "tuning". The idea is to crank it up with gain, so it becomes super-sensitive to whatever you are listening to, and adjust pitch and reverb, etc. for best sounds.

Have's a perfect Halloween activity!
frostybob1 year ago
So must this is almost like a mircophone then? As portable as the computer its plugged into. How easy would it be to record straight onto a tape without first going through a computer? I'm just generally wanting to take it outside and see what I can whilst out there
Any help would be much appreciated
mrfixitrick (author)  frostybob1 year ago
The radio does and can act as a microphone, among many other things. I have done a movie about that in fact. However, if you record straight onto tape, it will not have enough gain to hear much, or have any of the effects that create the ambiance. You might hear an AM station if you are lucky, along with plain static, for example.

An old MacBook would be the cheapest and best way to get the cool sounds while being mobile. Windows laptops may work with some software too.
Mvtnns1 year ago
Will the AA113 Ge diode work with this?
mrfixitrick (author)  Mvtnns1 year ago
The AA113 germanium diode is similar in function t the 1N34a, and may work in this application. I can't say for sure, as it is not a direct cross reference to the 1N34a. Try can't harm anything.

Perhaps another reader has more info on this diode?
It had been a week or two but here is my finished product
mrfixitrick (author)  TheFabricationist1 year ago
Cool! It looks really nice.

Can you get it to talk, that is the question! hehe

The Dell PC is harder than the Mac to use, but there was a comment I posted here below that goes like this...

" ...and PC program called Audio Mulch and it will work fine for the purpose of the Spirit Radio with a PC. It's expensive to buy, but you can download a 60-day free trial that works great .

I set up three "MGain" patches in the Audio Mulch software and it increased the volume enough to hear radio stations and electromagnetic fields clearly. Then I added various controls such as pitch and reverb for strange "spirit" effects.  "

Good luck and happy hunting!
So far I haven't gotten the voices yet. I downloaded the free trial of audio mulch but I know very little about it, I have been plugging my radio into a guitar amp and I get all the volume I need to hear a few am stations and the electromagnetic fields. I will tinker with audio mulch and let you know If I hear the voices.
I know very little if anything about circuits and radios. So my question is (and please forgive me is it is unbelievably stupid) could i open up any old analog AM radio and get the majority of the parts i need?
mrfixitrick (author)  TheFabricationist1 year ago
Some of the parts from an analog AM radio may work, including the antenna coil, a variable capacitor, and possibly a resistor or capacitor. However, the main item missing will be the 1N34a diode, which is particular to crystal radios and hard to find elsewhere. I have a 1500 page electronics catalog that doesn't have them!

You won't be able to get the parts from an analog radio, but you can simulate the effects by plugging in the audio out from the radio into the audio in of your computer. Then run software to increase the gain (volume) and alter pitch such as the suggested program Audio Hijack Pro on a Mac is best. There may be PC alternatives for software.

The technique would be to tune off-station, in the places where you normally hear static, then crank up the gain so that the background noise becomes what you listen to. However, you would not be able to have as much of a variety of other uses for the analog radio, as "Spooky" does.

Without the 1N34a diode, some of the trickier experiments like shining a laser on the diode, or hearing a lightbulb, won't be possible. Diodes are cheap...if you can find them!

Question, all the ferrite loopstick inducters i have seen have 4, 6 or even 8 wires coming out of it, to have different sizes of coils. How do i know witch one i need?
mrfixitrick (author)  Nicola Tesla1 year ago
The coil should have the micro-henrys indicated in the literature. Use the pair of wires closest to 680 uH. If you don't have that info, then experiment with each pair of wires to get the best signal.
Oppzuz1 year ago
Those signal pulses appear to be the WIFI "Beacon" set by default on my router to 100 milliseconds (10 Hz). Those are constant as long as the WIFI is enabled.
Have you tried to test if this receives radio waves or energy that can be converted into voltage through the use of a radiant energy device which through the use of a simple circuit converts radiant enrgy into voltage?

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