I built several different types of "Crystal" sets when I was just a kid way back in the 50's and 60's. Yup! The technology still works "As Advertised"! AM comes in loud and clear. Though I haven't tried it yet, there are even plans on the Web for FM receivers !
Great Video. If you can find Talenti Gelato in 328.8g plastic jars, they are just begging to be used in a Crystal Radio. They are 8.4mm wide by 10.4mm tall (with the screw on cap).
What's the "mystery"? it looks like an ordinary crystal set in the schematic, with the exception that the coil is tapped in a slightly different way. Is the mystery that you don't have an Aussie accent?
itisonlyadream The *”Mystery”* in the name comes from the fact that the antenna is not connected to ground by any means. It is attached to the rest of the circuit because the bifilar windings allow transformer/trans conductance effect. Here is a URL that I found to be very helpful in building my own radio: electronbunker.ca/eb/CrystalSet01.html
@@mtkoslowski Thank you for the explanation. The link you provided clearly shows that the set has two coils that are not connected, but the schematic that was held up before the camera in the UA-cam video showed what appeared to me to be a SINGLE coil that was directly connected to the detector section by physically tapping the coil below the top of the coil and above the bottom of the same coil. For this reason, , it was not apparent to me that there was no direct connection from the antenna circuit to ground. If I had seen the schematic shown in your link in the beginning, then I would have realized that the antenna to ground discontinuity was the "mystery". However, it wouldn't have been a mystery to me, because I would have realized that at radio frequencies the antenna circuit was capacitively coupled to the grounded section of the circuit. Thanks to the schematic in your link, I can see that this is an unusual design, but the only mystery to me is that it apparently works so well.
How Many Stations you Receiver can demodulate?A little Problem of piezo Headphones ist the Load and you hear sometimes nothing.A good Trick ist parallel a Resistor.. LG.Coilwinder Matthias
AM broadcast band reception hasn't much to do with distance to the station because of skywave propagation. A station barely audible at 100 miles distance, might be booming at 1,500 miles distance. As near as you are to Chicago, you might not ever hear WLS, while listeners in Georgia regularly will. The Mystery Radio, is supposed to be a real killer with a minimum of parts, but the ones I've built were just average performing sets compared to the better ones I've built. My Mystery radios all needed a 500pf variable capacitor to cover the entire AM band; I suspect your 365 doesn't quite cover the entire band. Also, I never noticed any real change in performance whether or not I used a capacitor/resistor parallel with the type phone I was using. If you want a real killer headphone set, buy a pair of piezoelectric buzzers (PT-4175WQ) and wire a 10-12k resistor in parallel with the two. Can't get any better! Thanks for the video.
A good Idea ist my original Telefunken Coil Crystal Detektor...History.With 2 Sliders ist the Detektor a galvanic Transformator!one Slider for Antenne and the Others for Tuning!
Mike, when you start with the 25 turns and continue with the other size wire, do you connect/solder them if not, what and where do the ends of both of the wires terminate? I see the schematic has them joining the diode on the top end and joining the Ground and one side of the Headphones on the other, correct?
Tecsun 200 ,I believe that's the number Its a loop antenna with a built in tunning capacitor ,you can set it next to your am radios ,close to where your ,inside antenna located and turn the tunning capacitor on your loop it improve your reception ,it also comes with a wire for direct hook up ,if you find me.on messenger ,I will send you a picture of it I think this will boost your signal for your crgstal set.I like your design Maybe someday you will do a.video on how you make.your Crystal sets
It would probably work a lot better with a ground connection at the opposite end of the coil to the antenna. The broad/sharp tuning switch appears to do nothing useful.
You miss the whole point of the "Mystery set"! The Capacitance between the Primary and the Secondary of the coil provides the necessary coupling, and the switch causes the amount of coupling (hence Selectivity) to change.
I need to know more about what turns how big and I'm getting a book sent to me from the 1920s I want to know all about these things I've already built a couple my best one is built from an Atwater Kent tuning coil and capacitor and I have a little Japanese one that was $0.59 brand new that will pick up anything and it only has one wire
What's the point of the 47K resistor? If the 47K resistor replaces the headphone capacitor, then it's in parallel with the headphones. In that case, it would seem that it would simply shunt some of the current, even though 47K is a very high resistance. So, compared to the low output voltage of a crystal set it can't shunt much current. I assume it's there for impedance matching, but I don't understand the theory of why it works. On the other hand, if the resistor is in series with the headphones, then it will drop some of the voltage and make less sense. I built crystal sets when I was a kid and they used a 2000 Ohm headset, so I used the traditional capacitor across the headphones. But, when I removed the headset capacitor it never seemed to make any difference, so I eventually eliminated the headset capacitor. These days I have a crystal set with a crystal earphone that I built with my nephew from a Radio Shack kit, but it has never worked. The kit didn't include the 47K resistor, so I wonder if that's the reason why it never worked. It was embarrassing when we connected the antenna and ground and couldn't hear a damn thing.
itisonlyadream Since you are sending only one polarity to the phone, it builds up a DC charge. The resistor lets the charge dissipate so it is more efficient.
@@stephenbaldassarre2289 That explanation might make sense to you, but it doesn't make any sense at all to me. The earphone is connected to a complete DC circuit, there's no "one polarity" involved, and if there was, then no current could flow through the earphone. The most amazing part of this to me is you got two thumbs up for that answer.
@@itisonlyadream The crystal earpiece acts somewhat like a capacitor in that DC will not pass through it. As charge of a single polarity builds up in it, it loses the ability to react to the incoming pulses (which are all the same polarity). The parallel resistor lets that build-up bleed off to the ground, allowing the crystal to operate more efficiently. Now if you use a voice-coil earpiece, which can pass DC, what you say is true and it will be more efficient without the resistor. The other solution would be to put in a transformer (which I have tried) to send the earpiece a true AC signal but that's more expensive.
@@stephenbaldassarre2289 Thanks for taking the time to clear this up, your new answer makes sense. I think the problem was the way you worded your first answer--- I couldn't picture "sending only one polarity to the phone", because that mental image didn't fit anything I'd been taught about electronics. If you'd said the signal is fluctuating DC after the diode detector and a crystal earphone acts like a blocking capacitor, so it needs a discharge path provided by the resistor, then I think I would have got the point the first time around. Some people say they use a crystal earphone and the volume is louder without the resistor. Maybe they have a leaky crystal in the earphone, or maybe they screw their terminals into a wood base that's not a good insulator.
I would assume the .001mfd that he had listed in the diagram. He mentioned using the capacitor for the 2000 ohm headset or the 47K resistor for the high impedance earphone.
My only regret is I wish I could like this video twice or more. Well done!
Now that's very cool and more portable than most,I hope u will do a step by step assembly of this unit.
I built one from the the Proton plans years ago and it still is my best performing set.
I built several different types of "Crystal" sets when I was just a kid way back in the 50's and 60's.
Yup! The technology still works "As Advertised"! AM comes in loud and clear.
Though I haven't tried it yet, there are even plans on the Web for FM receivers !
Nice show, love it.
Try to reduce the amount of winding to 5 for SW reception- Try to make FM crystal radio too. Thanks for your videos!
Great Video. If you can find Talenti Gelato in 328.8g plastic jars, they are just begging to be used in a Crystal Radio. They are 8.4mm wide by 10.4mm tall (with the screw on cap).
Great work. I am waiting with batted breath for your next video. LOL. Hurry up!
Good work and well presented. 👍
What's the "mystery"? it looks like an ordinary crystal set in the schematic, with the exception that the coil is tapped in a slightly different way. Is the mystery that you don't have an Aussie accent?
itisonlyadream
The *”Mystery”* in the name comes from the fact that the antenna is not connected to ground by any means. It is attached to the rest of the circuit because the bifilar windings allow transformer/trans conductance effect. Here is a URL that I found to be very helpful in building my own radio: electronbunker.ca/eb/CrystalSet01.html
@@mtkoslowski Thank you for the explanation. The link you provided clearly shows that the set has two coils that are not connected, but the schematic that was held up before the camera in the UA-cam video showed what appeared to me to be a SINGLE coil that was directly connected to the detector section by physically tapping the coil below the top of the coil and above the bottom of the same coil. For this reason, , it was not apparent to me that there was no direct connection from the antenna circuit to ground. If I had seen the schematic shown in your link in the beginning, then I would have realized that the antenna to ground discontinuity was the "mystery". However, it wouldn't have been a mystery to me, because I would have realized that at radio frequencies the antenna circuit was capacitively coupled to the grounded section of the circuit. Thanks to the schematic in your link, I can see that this is an unusual design, but the only mystery to me is that it apparently works so well.
@@mtkoslowski
Thanks for posting that link, the schematic makes a lot more sense when drawn properly.
How Many Stations you Receiver can demodulate?A little Problem of piezo Headphones ist the Load and you hear sometimes nothing.A good Trick ist parallel a Resistor..
LG.Coilwinder Matthias
May I get the dimensions of the tube? It looks larger than a Tolet Paper tube unless it's made for Australian Giants.
😂😂😂😂😂
This is terrific, can u tell us what frequency range this unit will recover
I have over 100 feet of possible usable wire. I like this.
1:56 Those are from the 1930's - - I have a pair just like them. Those that came out in the Forties were plastic case and lighter in weight
AM broadcast band reception hasn't much to do with distance to the station because of skywave propagation. A station barely audible at 100 miles distance, might be booming at 1,500 miles distance. As near as you are to Chicago, you might not ever hear WLS, while listeners in Georgia regularly will. The Mystery Radio, is supposed to be a real killer with a minimum of parts, but the ones I've built were just average performing sets compared to the better ones I've built. My Mystery radios all needed a 500pf variable capacitor to cover the entire AM band; I suspect your 365 doesn't quite cover the entire band. Also, I never noticed any real change in performance whether or not I used a capacitor/resistor parallel with the type phone I was using. If you want a real killer headphone set, buy a pair of piezoelectric buzzers (PT-4175WQ) and wire a 10-12k resistor in parallel with the two. Can't get any better! Thanks for the video.
I've had great results. But been modified Rf amp, PA speaker transformer and feedback. .
Good crystal radio.
A good Idea ist my original Telefunken Coil Crystal Detektor...History.With 2 Sliders ist the Detektor a galvanic Transformator!one Slider for Antenne and the Others for Tuning!
Hi, what outer diameter is your tube? Also how long is your antenna please? Or is that too personal? 🙄👍 (Serious questions though).
Mike, when you start with the 25 turns and continue with the other size wire, do you connect/solder them if not, what and where do the ends of both of the wires terminate? I see the schematic has them joining the diode on the top end and joining the Ground and one side of the Headphones on the other, correct?
The two coils are not joined. The secondary is just wound over the primary.
Nice! Love the variable capacitor.
Nice Job, I like it, it's compact and cool looking.. If you made it. You gotta put a "Made in USA" sticker on it.
"Made in USA?" I'm not (no longer) familiar with that term.
Very nice.
Thumbs up !
Hello..hola espero que puedas seguir subiendo más videos de armado de radios. Y de ser posible como armar para tener bien la SW de onda..
Thanks Mike. What is the actual diameter of the tube?
No mystery here just a regular crystal radio. Made these when I was a little boy.
Amazing Congratulations great job!!!
just another simple crystal set in a different enclosure
Wow 😲 valuable search 🔍
,😄♥️♥️🌎😄♥️
I have to make one of these!
Tecsun 200 ,I believe that's the number Its a loop antenna with a built in tunning capacitor ,you can set it next to your am radios ,close to where your ,inside antenna located and turn the tunning capacitor on your loop it improve your reception ,it also comes with a wire for direct hook up ,if you find me.on messenger ,I will send you a picture of it I think this will boost your signal for your crgstal set.I like your design Maybe someday you will do a.video on how you make.your Crystal sets
Переменный конденсатор из двух трубок понравился.
Smarty idea. Simply clever
saved for future reference .:) what do u use for antenna may i ask? thanks in advamce .
have you tried lighting leds with the CRs?
Nice radio
It would probably work a lot better with a ground connection at the opposite end of the coil to the antenna. The broad/sharp tuning switch appears to do nothing useful.
You miss the whole point of the "Mystery set"!
The Capacitance between the Primary and the Secondary of the coil provides the necessary coupling, and the switch causes the amount of coupling (hence Selectivity) to change.
I don't see ground coming out is it's ok?
i love it its great idea
I need to know more about what turns how big and I'm getting a book sent to me from the 1920s I want to know all about these things I've already built a couple my best one is built from an Atwater Kent tuning coil and capacitor and I have a little Japanese one that was $0.59 brand new that will pick up anything and it only has one wire
Ronald Daub
electronbunker.ca/eb/CrystalSet01.html
What's the point of the 47K resistor? If the 47K resistor replaces the headphone capacitor, then it's in parallel with the headphones. In that case, it would seem that it would simply shunt some of the current, even though 47K is a very high resistance. So, compared to the low output voltage of a crystal set it can't shunt much current. I assume it's there for impedance matching, but I don't understand the theory of why it works. On the other hand, if the resistor is in series with the headphones, then it will drop some of the voltage and make less sense. I built crystal sets when I was a kid and they used a 2000 Ohm headset, so I used the traditional capacitor across the headphones. But, when I removed the headset capacitor it never seemed to make any difference, so I eventually eliminated the headset capacitor. These days I have a crystal set with a crystal earphone that I built with my nephew from a Radio Shack kit, but it has never worked. The kit didn't include the 47K resistor, so I wonder if that's the reason why it never worked. It was embarrassing when we connected the antenna and ground and couldn't hear a damn thing.
itisonlyadream Since you are sending only one polarity to the phone, it builds up a DC charge. The resistor lets the charge dissipate so it is more efficient.
itisonlyadream i clipped it to see what happens and removing it reduces the volume.
@@stephenbaldassarre2289 That explanation might make sense to you, but it doesn't make any sense at all to me. The earphone is connected to a complete DC circuit, there's no "one polarity" involved, and if there was, then no current could flow through the earphone. The most amazing part of this to me is you got two thumbs up for that answer.
@@itisonlyadream The crystal earpiece acts somewhat like a capacitor in that DC will not pass through it. As charge of a single polarity builds up in it, it loses the ability to react to the incoming pulses (which are all the same polarity). The parallel resistor lets that build-up bleed off to the ground, allowing the crystal to operate more efficiently. Now if you use a voice-coil earpiece, which can pass DC, what you say is true and it will be more efficient without the resistor. The other solution would be to put in a transformer (which I have tried) to send the earpiece a true AC signal but that's more expensive.
@@stephenbaldassarre2289 Thanks for taking the time to clear this up, your new answer makes sense. I think the problem was the way you worded your first answer--- I couldn't picture "sending only one polarity to the phone", because that mental image didn't fit anything I'd been taught about electronics. If you'd said the signal is fluctuating DC after the diode detector and a crystal earphone acts like a blocking capacitor, so it needs a discharge path provided by the resistor, then I think I would have got the point the first time around. Some people say they use a crystal earphone and the volume is louder without the resistor. Maybe they have a leaky crystal in the earphone, or maybe they screw their terminals into a wood base that's not a good insulator.
Везёт же людям! На средних волнах вещание есть. А у нас, как на другой планете...
Так, так. Добре там де вас нема.
@@vitalik3273 यह एक अच्छी बात है कि हम वहाँ नहीं हैं
Can these radios be attached to a Joule Thief circuit so that you can amplify the voltage enough to charge a battery?
Francis Rodgers
No
How The Wave Trap Works , With The Radio ?
It is a pity that you did not do radio on transistors
bookmarked for future reference .:)
Nice!
The balanced set is only about 90 years out of date.
This particular design, “The Australian Mystery Crystal Radio” was demonstrated in 1932. electronbunker.ca/eb/CrystalSet01.html
@@mtkoslowski , LOL Only 2 years off... ROFL
What size is that ceramic capacitor?
I would assume the .001mfd that he had listed in the diagram. He mentioned using the capacitor for the 2000 ohm headset or the 47K resistor for the high impedance earphone.
365 picofarad, it looks like a variable air capacitor.
Гарна робота!🇺🇦
Am gonna make one
Faltou tradução.
✋73's🎙KD9OAM🎧