In my childhood, probably in the year 1979-1980 I used to listen local station using just two components and an antenna and ground. One was a headset and a germanium diode OA79. The headset was actually the headset of wired pulse dialing telephone. We used to connect the diode in series with the headset (as much as I can remember because I was only 4-5 years old back then) and connect one side to antenna and other end to the Earth. Voila you have a radio without any battery. As the radio station was very near to our home only 2 Km away, the sound strength was quite good. I still remember the number of the diode is because slowly these things got me into loving electronics and at those early days normal heterodyne 6 transistor Radio (3 for IF section and 3 for speaker amp) and cassette players all that we had to play with. I used to carry my single battery Panasonic Radio all the time.
Hello. The illegible writings in Russian on 0:46 leterally stands for "The measure of I_R was carried out. Tsanka", which means that all the diodes were tested for their reverse current. Then, it is signed "Tsanka", which is a first name of the person who carried out the test.
An awesome diode and an interesting video. Thanks. The diode looks like a very small vacuum tube. The tiny little parts inside, and the way the glass package is molded onto the leads. Cheers from Canada.
Adjustable ferrit rod inside the coil, was what I had on my first circuit for the tuning. That also worked very well and was a lot smaller than the wooden coil, anyway very informative stuff. 👍 I hope, they don't switch all stations to digital signal, because that would be the end for such easy circuits.
Here in the USA they’re trying to get rid of AM radio. Electric vehicles cause interference which has prompted the manufacturers to stop putting AM radios in electric cars. Now Ford has announced they will stop putting AM radios in ALL their vehicles, because *they know* we really don’t need that anymore... we’re supposed to stream AM stations over our mobile devices. Anyway, I suppose the next step is for AM stations to stop broadcasting because nobody can listen anymore.
Why worry about signals going digital? Just replace the analog germanium diode that decodes the AM signal with another (digital) diode that demodulates the COFDM modulation and decodes the HE-AAC v2 audio stream.
Excellent, Soviet made components work well. However, the "China express" will send a Shockley instead of a Geranium diode. I trust the Russian stuff, Japanese and American components are rarely sold in the open market here and are expensive, Parts houses only. Ebay CCCP gear is better than Red State CCP fake gear.
@@andygozzo72 The diodes he shows in this video are point contact diodes and each one was hand tuned. They don't make these anywhere anymore as the labor costs to individually tune them would be too high. The modern replacement diodes may be the same materials but they are not point contact and will not give you the same results in a crystal radio.
@@tenlittleindians the OA91 types i mentioned (and OA90) are point contact, and look identical to the ones in the video, get one and look into one with a magnifying glass and you'll see , theres also several earlier OA types with larger glass case
UPGRADE IT AGAIN to DVB using nothing but a rubber band, two broken toothpicks and some hot glue (everything gets better with lots and lots of hot glue)
Hi. Nice episode. Would love to see you upgrading it further. Maybe explain how to achieve tuning in to specific station of your choice. Can I use this radio to listen to FM stations? Also I have problem with finding earphones you use. How did you made it work with speakers? Is there any type of modern diode that will make it work? Those soviet ones are hard to get ;)
Well... 1- The station is chosen by modifying the position of the coil wire. 2- No FM, only AM 3-Cristal earphones, or any speaker would work, if it don't need a lot of voltage nor current. 4- Every diode would work. The Cat's Whisker, or the Razor Blade, works by making exactly the same job as any diode. Just use it in the correct position.
That's the "fun" of these types of radios. If you can tune it high enough to the FM frequencies you can sort of hear it. The FM messes with the AM detection. I've done this and it works but it's much weaker than AM so it will be very quiet. If you can't find the crystal radio you can use a regular audio amplifier with a speaker. It's "cheating" by using batteries but it's useful for just playing with. I've seen some people use a custom made impedance matching audio transformer. The radio has a very high output impedance. A transformer that can couple the high radio impedance to a low impedance speaker does work. Tuning is done by whatever means you can use. Changing the inductance uses the least amount of parts. Adding capacitors is another way of tuning. If you make the radio so that it's easy to swap in different diodes, then make the radio and start trying different diodes. Some diodes will work better at different frequencies. A small schottky diode might work. I've used a red LED before (only good on really strong stations). The thing to do is play with the parts and see what works and how well they work. This radio is less a science and more an art.
@@isaacm1929Modern diodes have a higher forward voltage and won't work as a direct substitute in this circuit. I think it might be possible to bias a modern diode using a potato as a battery along with a properly sized resistor. You would still need a crystal ear piece for listening unless you added an amplifier section to this radio circuit. Make that amplifier section potato powered too for real trench war conditions.
@@therealjammitAM radio is "amplitude modulated" and FM stands for "frequency modulated". It's not as simple as adjusting the coil to a different frequency range.
@@tenlittleindians Yeah. I forgot that. Most diodes today need bias. (But it is still possible to find modern diodes with low forward voltage in some places. ) Thanks for correcting my comment! Also, potatos are a valuable source of food, so, in war, maybe lemon power would be better.
These radios are getting their voltage directly from the frequency waves hitting the antenna. A hundred years ago they maximized this by increasing the length of this antenna and often ran a long wire out a window to a barn or tree over a hundred feet away. The length of these long wires work best if they are either multiples of or fractions of the wave length of the frequency you are trying to tune in. Those long antennas were insulated from ground at both ends by ceramic insulators about 2" long which I still see for sale in antique shops. Usually they are white or blue with a hole on each end. They had an alligator clip on the wire from the radio to this long antenna so they could disconnect it during storms to prevent lightning strikes from traveling down the antenna and burning their houses down.
Ich bin älter als Du und wickelte 20 Jahre empfindliche Radiospulen mit schmalem Dip und hoher Güte(16Radiosender passiv nachts empfangen).wenn dein Ohrhörer mal nicht geht,halte ihn an eine Batterie oder schalte ein 3,3kohm R parallel.🤐💖🎹🛌🤸🤸🤸😢Russendioden sind gut,
ANY germanium diode should work, to some extent, doesnt have to be russian, a common one was OA91, although no longer made, theres likely still many around
In my childhood, probably in the year 1979-1980 I used to listen local station using just two components and an antenna and ground. One was a headset and a germanium diode OA79. The headset was actually the headset of wired pulse dialing telephone. We used to connect the diode in series with the headset (as much as I can remember because I was only 4-5 years old back then) and connect one side to antenna and other end to the Earth. Voila you have a radio without any battery. As the radio station was very near to our home only 2 Km away, the sound strength was quite good. I still remember the number of the diode is because slowly these things got me into loving electronics and at those early days normal heterodyne 6 transistor Radio (3 for IF section and 3 for speaker amp) and cassette players all that we had to play with. I used to carry my single battery Panasonic Radio all the time.
Hello. The illegible writings in Russian on 0:46 leterally stands for "The measure of I_R was carried out. Tsanka", which means that all the diodes were tested for their reverse current. Then, it is signed "Tsanka", which is a first name of the person who carried out the test.
I like how he just randomly gave the most clear explanation how radio tunes to different signals i've seen or read.
A crystal radio is a must have especially during a natural disaster.
An awesome diode and an interesting video. Thanks. The diode looks like a very small vacuum tube. The tiny little parts inside, and the way the glass package is molded onto the leads. Cheers from Canada.
This was a great explanation of how a foxhole radio works. Well done and thank you 👍😊
Adjustable ferrit rod inside the coil, was what I had on my first circuit for the tuning. That also worked very well and was a lot smaller than the wooden coil, anyway very informative stuff. 👍 I hope, they don't switch all stations to digital signal, because that would be the end for such easy circuits.
Here in the USA they’re trying to get rid of AM radio. Electric vehicles cause interference which has prompted the manufacturers to stop putting AM radios in electric cars. Now Ford has announced they will stop putting AM radios in ALL their vehicles, because *they know* we really don’t need that anymore... we’re supposed to stream AM stations over our mobile devices. Anyway, I suppose the next step is for AM stations to stop broadcasting because nobody can listen anymore.
yea in the USA digital radio stations exist which has analog and digital
Why worry about signals going digital?
Just replace the analog germanium diode that decodes the AM signal with another (digital) diode that demodulates the COFDM modulation and decodes the HE-AAC v2 audio stream.
Very good video. I enjoyed seeing the signal on the oscilloscope. I don't have the equipment to do that.
Wow....excelent!!!....all of this...was my childhood dream!!
Very very thanks nice models I like your teaching style your looking good beautiful I love fox hole radio and radios🤗🙋🙋🧘from india
1969 год - раритет. неокрашенные :) Nice kaizen radio!
Very nice explanation bro, nice work please do more on radios
you could take apart a cassette player to get an amplifier for the weak signals produced by this circuit. that would allow using it with earphones
Аккуратнее с ними!) А лучше вообще не включай )
Impedance, impotence One happens to electricity, the other to older men. *smile You are brilliant and I enjoy your videos.
Very Nice Vid Well Explained New Subscriber Thanks for Sharing
Thank you, So clear
very usefull
I Hav eHundreds Of Soviet Germanium Diodes, Selenium rectifiers And Ton Of Other Components !
COOL VIDEO ! SUPER COOL !
Excelente 👍
Saludos desde Argentina 🇦🇷👋
What was the voltage drop of the blade-pencil diode?
oh my gooooood! i need to find the same box!!!!!
Hard to find thats diode in indonesia..you are very lucky
Excellent, Soviet made components work well. However, the "China express" will send a Shockley instead of a Geranium diode. I trust the Russian stuff, Japanese and American components are rarely sold in the open market here and are expensive, Parts houses only. Ebay CCCP gear is better than Red State CCP fake gear.
you can usually still find suppliers of germanium diodes such as OA91 or equivalents
@@andygozzo72 The diodes he shows in this video are point contact diodes and each one was hand tuned.
They don't make these anywhere anymore as the labor costs to individually tune them would be too high.
The modern replacement diodes may be the same materials but they are not point contact and will not give you the same results in a crystal radio.
@@tenlittleindians the OA91 types i mentioned (and OA90) are point contact, and look identical to the ones in the video, get one and look into one with a magnifying glass and you'll see , theres also several earlier OA types with larger glass case
@@andygozzo72 Here's a great breakdown of diodes old and new: th-cam.com/video/2yzr4kx8SJ4/w-d-xo.htmlsi=4S9WXoDeDaTCXK_z
If you havent already, try a lead sulphide crystal cluster
UPGRADE IT AGAIN to DVB using nothing but a rubber band, two broken toothpicks and some hot glue (everything gets better with lots and lots of hot glue)
Can you somehow increase the volume of blade pencil setup, like making a primitive amplifier from stratch.
very clear
Very interesting 👌
so clear
Hi. Nice episode.
Would love to see you upgrading it further. Maybe explain how to achieve tuning in to specific station of your choice.
Can I use this radio to listen to FM stations?
Also I have problem with finding earphones you use.
How did you made it work with speakers?
Is there any type of modern diode that will make it work?
Those soviet ones are hard to get ;)
Well...
1- The station is chosen by modifying the position of the coil wire.
2- No FM, only AM
3-Cristal earphones, or any speaker would work, if it don't need a lot of voltage nor current.
4- Every diode would work. The Cat's Whisker, or the Razor Blade, works by making exactly the same job as any diode. Just use it in the correct position.
That's the "fun" of these types of radios. If you can tune it high enough to the FM frequencies you can sort of hear it. The FM messes with the AM detection. I've done this and it works but it's much weaker than AM so it will be very quiet.
If you can't find the crystal radio you can use a regular audio amplifier with a speaker. It's "cheating" by using batteries but it's useful for just playing with. I've seen some people use a custom made impedance matching audio transformer. The radio has a very high output impedance. A transformer that can couple the high radio impedance to a low impedance speaker does work.
Tuning is done by whatever means you can use. Changing the inductance uses the least amount of parts. Adding capacitors is another way of tuning.
If you make the radio so that it's easy to swap in different diodes, then make the radio and start trying different diodes. Some diodes will work better at different frequencies. A small schottky diode might work. I've used a red LED before (only good on really strong stations).
The thing to do is play with the parts and see what works and how well they work. This radio is less a science and more an art.
@@isaacm1929Modern diodes have a higher forward voltage and won't work as a direct substitute in this circuit.
I think it might be possible to bias a modern diode using a potato as a battery along with a properly sized resistor. You would still need a crystal ear piece for listening unless you added an amplifier section to this radio circuit.
Make that amplifier section potato powered too for real trench war conditions.
@@therealjammitAM radio is "amplitude modulated" and FM stands for "frequency modulated". It's not as simple as adjusting the coil to a different frequency range.
@@tenlittleindians Yeah. I forgot that. Most diodes today need bias. (But it is still possible to find modern diodes with low forward voltage in some places. )
Thanks for correcting my comment!
Also, potatos are a valuable source of food, so, in war, maybe lemon power would be better.
They are very pretty.
You have a lot of thats dioda..I cant find just one piece here in indonesia ...
You got a lot..here is hard to find
Ive been trying to do a foxhole radio but it doesnt seem to work, in my mind a cristal earplug must be the same as a small speaker right?
How can I get it in India Chennai
I think you mean "Impedance". Impotence is what happens to you as you age.
Can you use multiple diodes in a single crystal radio and see how much voltage output?
no, no point,
These radios are getting their voltage directly from the frequency waves hitting the antenna.
A hundred years ago they maximized this by increasing the length of this antenna and often ran a long wire out a window to a barn or tree over a hundred feet away.
The length of these long wires work best if they are either multiples of or fractions of the wave length of the frequency you are trying to tune in.
Those long antennas were insulated from ground at both ends by ceramic insulators about 2" long which I still see for sale in antique shops. Usually they are white or blue with a hole on each end.
They had an alligator clip on the wire from the radio to this long antenna so they could disconnect it during storms to prevent lightning strikes from traveling down the antenna and burning their houses down.
Im-peed-ance.
Діод як діод.
Ich bin älter als Du und wickelte 20 Jahre empfindliche Radiospulen mit schmalem Dip und hoher Güte(16Radiosender passiv nachts empfangen).wenn dein Ohrhörer mal nicht geht,halte ihn an eine Batterie oder schalte ein 3,3kohm R parallel.🤐💖🎹🛌🤸🤸🤸😢Russendioden sind gut,
bravado
Very, very good. I'm a EE, and I could not have done anywhere is well.
For the translator it sounds like you’re pronouncing “impedance” as “importance”.
He is…
Can you give me 5 of germanium diodes.
Sir i want Russia germanium diode how can I get it
ANY germanium diode should work, to some extent, doesnt have to be russian, a common one was OA91, although no longer made, theres likely still many around
Thank you 👍 😅@@andygozzo72
@@srinivasanvenkataraman3879 other ones OA90, OA81, OA70, OA71, OA79, AA119, .. OA5 or OA10 'may' work ...
Commie diodes.😆