I built one of these when I was 12 years old.....I wound wire on a toilet paper tube for days with wax paper in between the coils....It didn't work....So, I did it again winding onto a paper towel tube and keeping the wire at a single thickness....It worked! I learned to improve the audio output with a bigger coil. Everything was going fine until I "invented" a better antenna and was installing it in our attic. I accidentally stepped between the rafters and feel halfway through my parents bedroom ceiling.......My fledgling radio career very nearly came to a end..... Hey Dad....THIS is a VERY GOOD project to share with your kids.... KF7ZSA
Nice job. My grandfather built one of these with me as a child. 30 years later, I still love electronics. Everyone should build at least 1 crystal radio from scratch.
Yes, but only if you can put up a long wire antenna and a proper grounding. I just built a crystal set and I can hear some stations at night, BBC, some russians, Romania... The nearest MW stations are abt 1000 miles away from me.
Isse behtar kisi ne bhi radio project ko nahi banaya ...sab koi ya toh resister ya fir capasiter use karke hi bataye hai aur uska karan bhi kabhi nhi btaya...aapka project lajawab hai sir hatss off
I would stay up late at night and tune into Ira Blue at the Hungry Eye (50,000 watts) in San Francisco from my childhood home in Coquille Oregon......55 years ago.........................gently, gently, ever so gently probing that razor blade with my pencil lead secured to a bent safety pin and my ears stinging from the plastic headset.... Sometimes, rarely but sometimes...I could hear foreign language radio......Where is this from, I would wonder.......... KF7ZSA
The detector is metal-oxide-carbon. There is a physics effect that says that an electron can go some distance into an insulator like metal oxide. This distance is tiny and depends on what the electron starts out in. You can think of it as depending on the speed of the electrons in the material. The "speed" is very different for carbon and iron. Thus electrons can make it right through the oxide on only one direction.
Finally! Someone gets it. These are TUNNEL DIODES but *not* semiconductors. They are MIM tunneling diodes which stands for Metal-Insulator-Metal. The Work Function of the two metals (or carbon must be different because electrons move in both directions and one direction must exceed the other for useful detection to result. @@kensmith5694
Speaker doesn't amplify the signal!!! Does anybody know how the frequency domain response of an LC circuit ? And y the inductor doesnt allow sudden changes in the current flowin through? "Jw" ??
The Old Gillires Blades in 1940's was made of different metal in 1945. My Grandfather was in WW2 as a Batann Death Marcher & POW. He Build me one in 1956 it had to be Gillettes "BLUE" COLOUR. The NEW pincels also are not GRAPHITE in USA. Gotta get ATIST PINCIL. I have a set of Watercolours and they won't work.Oh I seen HOW you MAKED a BLUE BLADE...Oy Vey! How syupid are I am?Nu? But the Foxhole Radio in the POW Camp was DETECTED DRIVEN. No Ciols, because (As Grandfather explain) ONLY ONE STATION IN ROAD JAIL where he at was.
Good job! Your fox-hole radio worked better than mine. The signals I got using the razor blade was so weak. I could hardly hear anything. I'll keep trying. PEACE !
Into the 2 minutes mark, your background voice, and your cellphone emissions are bleeding upon the ground which emitting data transmission over your speaker of the cellphone.
Yes but u need to have a really big antenna and be close to the staation for it to work. Otherwise youll only hear a whisper if it works. Instead get the thing that beeps in a microwave or similar piezo type speaker. I use regular hedphones and get decent volume on mine. If u have them give it a try and see if it works for you
You Tube this Engine er did not understand the how make radio my request this engi ner take help from so lding iron than he will Successful.You Tube Yrs every program goi ng very wel.Thanks.
The only catch to this is that you need a very high impedance earpiece or headphones, otherwise you will hear nothing, I built many crystal sets as a kid and used a crystal earpiece.... I went on to become a chartered radio consultant
I built ine using a 1n34 diode and i can use magnetic stereo hedphones just fine. It sounds like pocket radio on comfortable low volume. I get am 650 and one Mexican station depending on the chosen coil tap.
yes fox hole catches AM signals. Usually AM's radio signal strength will not be good if it crosses 250-300 km. but if the radio brodcaster amplify enough its quite possible,
@@huseyinuguralacatli5064 That would be EXTREMELY rare. You would need an excellent antenna, a diode, probably a 5 stage radio, even then it would be highly unlikely. You might be able to hear Shortwave 5000 km away, with all that I said above. A foxhole radio like this with a good antenna and ground, tuned with a capacitor instead of inductance could hear an AM (MW) station 500km away at the right time of the year and the right time of the day. I've done it.
Joanna Siddika, remove bit of pencil's wooden body until u see graphite inside. Then wind wire ending around pencil and tighten it. Make sure wire ending is in contact with graphite.
Hi sir! can i use copper wire for everything, or should it be covered enameled? what kind of pencil did you use sir, graphite or lead? please reply, it would greatly help, thank you in advance :)
किन तारों को तुमने स्पीकर से जोड़ा है, बताया नहीं । रेडियो सेट को इधर से उधर बार बार इतना हिलाते रहते हो इस कारण दिखाई नहीं देता है कौन तार किस चीज़ से जुड़ा है ।
0:27 Why? Because everybody needs a hobby! 2:40 Don't you have single-edge razor blades and super-glue in your country? 7:25 You clearly have very little experience with this.
John Smith - you sound like you learned something new...you were paying to much attention to it. Don't be an azzhole, be appreciative to what you learned today
Dude, I cannot watch your video, you move the camera way too much... I get dizzy and my eyes bother when I tried to watch. Suggestions:? Get someone to help you hole the camera while you are working on projects. ( You have knowledge..
I built one of these when I was 12 years old.....I wound wire on a toilet paper tube for days with wax paper in between the coils....It didn't work....So, I did it again winding onto a paper towel tube and keeping the wire at a single thickness....It worked!
I learned to improve the audio output with a bigger coil.
Everything was going fine until I "invented" a better antenna and was installing it in our attic. I accidentally stepped between the rafters and feel halfway through my parents bedroom ceiling.......My fledgling radio career very nearly came to a end.....
Hey Dad....THIS is a VERY GOOD project to share with your kids....
KF7ZSA
Shall the wire around the cylinder be insulated or not??
@@sugampandit
INSULATED! Otherwise you just have a chunk of copper....
That made my night lol
Lol 😂🤣 🤣
How does one feel halfway though your parents ceiling haha
Nice job. My grandfather built one of these with me as a child. 30 years later, I still love electronics. Everyone should build at least 1 crystal radio from scratch.
Yes, but only if you can put up a long wire antenna and a proper grounding.
I just built a crystal set and I can hear some stations at night, BBC, some russians, Romania...
The nearest MW stations are abt 1000 miles away from me.
11 years later,...
... ...and
It still works !!!
👏👏👏
I built that today and it worked ! Thanks for posting
Really
هل اشتغل
"You will need a piece of wooden wood" every 60 seconds in Africa a minute passes
Thank you. You simplified a lot of complicated stuff
My name is John connor, if you are listening to this, you are the resistance .
We've been waiting a very long time. Hurry time is running out.
Phir prasun singhal kaun hai
Isse behtar kisi ne bhi radio project ko nahi banaya ...sab koi ya toh resister ya fir capasiter use karke hi bataye hai aur uska karan bhi kabhi nhi btaya...aapka project lajawab hai sir hatss off
They did build these during their time in the camps. ...Yours is the best foxhole radio video !
I absolutely love your projects! My all-time favorite!!
Necessary piece of tech if this pandemic goes outta control
Very enjoyable wish you would update this with a tripod with your camera
The camera motion was too much for me.
BUILT ONE OF THESE YESTERDAY , GOT AN OLD JACK BENNY PROGRAM
I would stay up late at night and tune into Ira Blue at the Hungry Eye (50,000 watts) in San Francisco from my childhood home in Coquille Oregon......55 years ago.........................gently, gently, ever so gently probing that razor blade with my pencil lead secured to a bent safety pin and my ears stinging from the plastic headset....
Sometimes, rarely but sometimes...I could hear foreign language radio......Where is this from, I would wonder..........
KF7ZSA
Wow, you built a time machine radio!
Does it need batteries
He is from karnataka
What turns actually means, why not less or more turns,
What ia the role of wire width
Mine picked up some guy named Alf from some place called Melmac.
how many turns of wire, and what gauge wire.
Finally found a real video😊
Also called POW Camp radio.
If there is a local radio station 12km from my house, will this crystal radio reproduce its sound?
nice explaination sir,,,pleaese do upload more video
Brilliant job!
I Feel Happy , ಕನ್ನಡ
😁🤘🤘
Ond sala hadiddu innond sala haaderodu
🙏🏼
Great 👍🏼 video.......Can I just connect the audio output to a earphone for my smart phone? So no need any source of electricity!!!
Can make it without using any coil????
can you use crystal earpiece
If you make a much longer coil like several feet wouldn't you hear in other frequencies. Why does home,aides ones a
Ways stop so short
Where or how to obtain the earphones
You would get better reception by connecting antenna at the very end of the coil as it matches the antenna to the rest of the circuit.
wish I understood better.......... why blueing the metal blade effects, etc
The detector is metal-oxide-carbon. There is a physics effect that says that an electron can go some distance into an insulator like metal oxide. This distance is tiny and depends on what the electron starts out in. You can think of it as depending on the speed of the electrons in the material. The "speed" is very different for carbon and iron. Thus electrons can make it right through the oxide on only one direction.
Finally! Someone gets it. These are TUNNEL DIODES but *not* semiconductors. They are MIM tunneling diodes which stands for Metal-Insulator-Metal. The Work Function of the two metals (or carbon must be different because electrons move in both directions and one direction must exceed the other for useful detection to result. @@kensmith5694
Speaker doesn't amplify the signal!!! Does anybody know how the frequency domain response of an LC circuit ? And y the inductor doesnt allow sudden changes in the current flowin through? "Jw" ??
Would it work if we give 80 turns
Yes
Yes
Is the wire around the cylinder insulated????//
Offcourse
Great video! I'm gonna try this!
Diameter of enamel wire? and diameter turn?
A good diameter would be 1.5 yo 3 inches. Use #24 to #30 gauge wire. Enamel coated.
Does it need batteries....?
Why is that blade heated can anyone explain
It had a coating on it to help keep it sharp. Heating it cleans the impurities off the blade for a better connection.
To create a layer of oxide (rust) on the blade. Along with the pencil, it forms a schottky diode.
Why don't you show arrangements of wire ... we cannot understand the series of wire of how and where it conn6
How do I get a wooden wood?🤔
It should grow from a wooden wood tree.
The Old Gillires Blades in 1940's was made of different metal in 1945. My Grandfather was in WW2 as a Batann Death Marcher & POW. He Build me one in 1956 it had to be Gillettes "BLUE" COLOUR. The NEW pincels also are not GRAPHITE in USA. Gotta get ATIST PINCIL.
I have a set of Watercolours and they won't work.Oh I seen HOW you MAKED a BLUE BLADE...Oy Vey! How syupid are I am?Nu?
But the Foxhole Radio in the POW Camp was DETECTED DRIVEN. No Ciols, because (As Grandfather explain) ONLY ONE STATION IN ROAD JAIL where he at was.
Good job!
Your fox-hole radio worked better than mine.
The signals I got using the razor blade was so weak.
I could hardly hear anything.
I'll keep trying.
PEACE !
Attach output to an i-amplifier like this for better results.
You need a longer antenna or a better headphone most likely
We dont need a capacitor because of stray capacitance of the circuit right?
Into the 2 minutes mark, your background voice, and your cellphone emissions are bleeding upon the ground which emitting data transmission over your speaker of the cellphone.
A friend and I built several as kids- they never worked. Oh well.
i already have a wire spool but it has 300+ turns, will it work?
You have a ground in your power socket and the usb in the power bank also has a ground why do all this to run a cable outside
Does it needs batteries.....
No.
I have old tv's speakers and i am not sure that if they would work without power if attached to this radio
They wouldn't. Insignificant power from the antenna to drive them. That's why you have to use the earpiece.
Yes but u need to have a really big antenna and be close to the staation for it to work. Otherwise youll only hear a whisper if it works. Instead get the thing that beeps in a microwave or similar piezo type speaker. I use regular hedphones and get decent volume on mine. If u have them give it a try and see if it works for you
Does it need batteries....?
They didn't have USB connectors in a fox hole!
There warnt no foxes in there neither.
They would have used a piezo speaker and not a speaker with an amplifier
They would have used a 2000 ohm or larger magnetic headphone during WWII.
Most people in the hobby prefer magnetic phones over piezo or amplifiers
Can we use copper wire as anteena?
yes, you can
can you use copper wire for ground?
@@aidan5077 Yes
Bom de mas ne mosso
Why does it have to be a razorblade?
It has to be a razor blade with oxide which forms a primitive diode. New, shiny blades dont work.
It doesn't. A knife blade or a hacksaw blade will work
I figure that could be another piece of rusty steel.
amazing
Were do i put electricity
Power goes to the i-amplifier not the radio.
Are such strong disturbances in India?
Tanks bro
that pencil must be sharpen so it can pick up more station
Can i use a simple 4007 diode..?
You Tube this Engine
er did not understand
the how make radio
my request this engi
ner take help from so
lding iron than he will
Successful.You Tube
Yrs every program goi
ng very wel.Thanks.
मैंने बहुत कोशिश की मगर बन नहीं पाया,
मुझे ज़्यादा अंग्रेज़ी नहीं मालूम,
हिंदी में में कोई सटीक लेक्चर you tube par नहीं है ।
*हाय रें बदनसीब हिंदी ।*
Kannad Chanel 🤗🤗🤗
Kas kelay jara samajaun sangal ka
Oh! Mr. Okay or you okay with your okays. Bye OK.
Its Kannada Channel ,Our language
جيد ولكن كم قطر الملف وعدد اللفاة ..وماهي قيمة الحث للملف ارجوا الاجابه
بقطر خمسة سنتيمترات وما بين مائة ومائة وعشرين لفة
Awesome...
Fabulous
hello is me TomyYoung! 📻
ಸೂಪರ್ ಕಣಪ್ಪ
The only catch to this is that you need a very high impedance earpiece or headphones, otherwise you will hear nothing, I built many crystal sets as a kid and used a crystal earpiece.... I went on to become a chartered radio consultant
I built ine using a 1n34 diode and i can use magnetic stereo hedphones just fine. It sounds like pocket radio on comfortable low volume. I get am 650 and one Mexican station depending on the chosen coil tap.
Its worked!
Bro..... does it need batteries....?
Nice but more Sssssss in your voice....
ಕನ್ನಡ 😍
Will it work in india also
works anywhere where am radio works
So dark man are you making video at midnight
Can it catch AM signal from radio station which is 500 kms away?
yes fox hole catches AM signals. Usually AM's radio signal strength will not be good if it crosses 250-300 km. but if the radio brodcaster amplify enough its quite possible,
once 20 year in night you can catch stations from 4500-5000km away
@@huseyinuguralacatli5064 😂🤣
@@huseyinuguralacatli5064 That would be EXTREMELY rare. You would need an excellent antenna, a diode, probably a 5 stage radio, even then it would be highly unlikely.
You might be able to hear Shortwave 5000 km away, with all that I said above.
A foxhole radio like this with a good antenna and ground, tuned with a capacitor instead of inductance could hear an AM (MW) station 500km away at the right time of the year and the right time of the day. I've done it.
And he is an indian
Tarif karu mai kya uske jisne ise banaya
I made a similar one but using a penny instead of the blade
I used a 150 year old penny. Decades of oxidation patina
Does it need batteries
@@charankrishna2214 no
How did you attach the wire from the diode to the speakers?
Joanna Siddika, remove bit of pencil's wooden body until u see graphite inside. Then wind wire ending around pencil and tighten it. Make sure wire ending is in contact with graphite.
I make this but with germanium diode
Yes a diode works better. A more pleasant clear sound as a bonus.
Yes
Ok
good
Thanke you
Nice nice
a piece of wooden wood? XD i only have metal wood. XD
You think you're funny but in America people have decks made of plastic wood.
@@rageonyx why would they call plastic wood?
@@nitindasiah991 wood design painted on
Amazing
Can you capture FM waves؟
AM waves are identical to sound waveform, but FM is frequency modulated. hence it will be highly difficult.
How long can you pick up radio stations?
I tried this setup from 100kms away from the radio station. AM is long range so signals will be available even from greater distance
No
Yes, but the signal is very very week even if you are close to an FM station. You would use a different size coil for FM
Hey. Why did you heat the blade? Do we have to do that everytime?
A rusty blade or flamed one is to create a diode like component.
Ok. thank you. But, do we have to heat it everytime?
Nope
Great. Thank you, once again.
You only need to hear it once to oxidize it. You could also soak it in salt water overnight to cause it to be rusty.
Fox hole radio is a myth .where did they get the head phones ?
Hi sir!
can i use copper wire for everything, or should it be covered enameled?
what kind of pencil did you use sir, graphite or lead?
please reply, it would greatly help, thank you in advance :)
Enameled. Use sandpaper to remove the enamel for making connections.
@@Pygar2 thank you so much sir!
i am so honored for your reply, greatly appreciated :)
Mam, the black stuff in the middle of a wooden pencil is what you want to use. It's really graphite but we mistakenly call it "lead".
All the best.
If you can make a coil without getting each turn in contact with the other.
Lol wooden wood
Man you can hear that 50hz WOW!!!!
I also make a radio
To baja kya??
Bad bad bad
Thisssssssssssssssssssssssss russsssssssted
किन तारों को तुमने स्पीकर से जोड़ा है, बताया नहीं ।
रेडियो सेट को इधर से उधर बार बार इतना हिलाते रहते हो इस कारण दिखाई नहीं देता है कौन तार किस चीज़ से जुड़ा है ।
Bro wo jo 1 pencil se nikl rh h n taar wo r tumhara earthing wala jod do
S T T B=√Spk=√Silet prekwensi kasad Tni dpel ad Trimpot Brigif frada am radio oldieS
Bruh what
0:27 Why? Because everybody needs a hobby!
2:40 Don't you have single-edge razor blades and super-glue in your country?
7:25 You clearly have very little experience with this.
John Smith - you sound like you learned something new...you were paying to much attention to it. Don't be an azzhole, be appreciative to what you learned today
where is battry
No need. It runs off of the power received through the antenna.
In the sky
It runs off the tiny amount of power in the radio waves
Why are say sssssssssssssss
Dude, I cannot watch your video, you move the camera way too much... I get dizzy and my eyes bother when I tried to watch. Suggestions:? Get someone to help you hole the camera while you are working on projects. ( You have knowledge..
Your hand movements and camera movements are too erratic. I have a headache.