For that you'll need a different circuit. In the description to this video I give a link to Charles Wenzel's website. You'll find other amplifier circuits there.
Had to give you a shoutout. Really like your videos. You have a real knack for explaining these concepts in a way I never could. Ive incorporated many of the ideas from your experiments and some others ive seen online into my build, all the way from simple adds like the resistor + cap combo to get around the germanium leakage limitation on up to a small solar panel driven audio amplifier for a HiFi headset I use (a pair of Pioneer SE-500 piezoelectric HiFi headphones!). I started my first using two Michelob Ultra beer cans ... one sliced down the side and sheathed over the other with cooking parchment paper between ... similar to the concept of the foil one demonstrated here.
I didn't do that because it would make a very boring video for most people. Also, I was hoping I gave enough instructions so people could do it by following the circuit diagram that I show, for example at 2:12. But I guess if you are very new to all this it still may be difficult. So I will make a companion video with all the steps shown, but since I won't be able to do it for a week or two, see if you can do it by following the diagram and the basic instructions I gave in this video.
Thanks! I added them to the video's description. I assume since it worked you've answered your own question, that yes, you can use non-polar 50v 1uf capacitors. I didn't know you could get non-polar ones with that high a capacitance. I think that's the only reason polar ones were specified.
FETs, Field Effect Transistors are marked Gate, Source and Drain. The 2N4401, the one used in this video, is a bipolar junction transistor which used Emitter, Collector and Base.
As promised, I've made the video you asked for. See my latest video called "Steps for How to Make Amplifier for Crystal Radio Earpiece" that has every step shown where I put each part in the breadboard. I've put a link to it at the end of this video and in the description below this video or you can find it on my channel page. I hope it helps. -Steve
tom leroux just mentioned below that he had success with 2n3904 and 2n2222, so you're not limited to 2n4401. All I can suggest re the BC548 is give it a try. But let us know so I can add it to the list in the video description.
I use Sony Vegas Movie Studio but if you're referring to the part where I show different colored rectangles and red arrows overlayed on a photo of a breadboard, I created a bunch of separate transparent background GIF images of just the rectangles and/or arrows using OpenOffice Draw. Then in Sony Vegas I put the breadboard photo in one track and then put the transparent background GIF images one at a time in a separate track. Crude, but effective. I recorded the audio separately.
The 100k resistor is the collector load resistor, and this should have about half the battery voltage across it. The current is about 1/20th of a milliamp or 50 microamps, which is so small that the battery should last for a very long time, maybe months. Yes, 82k is an uncommon value, so use 100k. How long should the antenna be? Thanks.
@1:14 I think that's what caused the time machine to go backwards in Back to the future? No no that was flux capacitor right! Man you are far more intelligent then I good sir. This is way beyond my understanding, but the result is pretty damn neat!
on the transistor will a 2n3904 or 2n2222 thay are npn type switching transistors and i got 2n3906 and thay are pnp transistors i have will one of them work at all
I don't see any problem with an RCA connector. Do you mean the old style magnetic earphones that people used to use with crystal radios before piezoelectric earpieces came along? If so I can't say for certain but I suspect they would work. You'll just have to try it to know for sure. Let us know. That also reminds me that I want to try and make a set of these magnetic earphones.
I don't understand this circuit fully. It's one I got from the website I mention in the description. I would like to know it better! I know the 82kohm resistor and the 0.001uF capacitor are regular crystal radio improvements (see my new How a Crystal Radio Works video for those.) Also, a capacitor is often used in series to filter out DC. And the 10Mohm resistor may be for protecting the transistor's base. Without all that might work, but may not sound as clear.
does it matter what kind a resistors or capacitors you have? or just the resistors: 82 kilo ohm, 100 kilo ohm, 10 mega ohm capacitors: 0.001 microfarad, 2 x 1 microfarad, 10 microfarad. thanks
Also another question, I want to use this amplifying circuit with say an RCA connection, so that the positive touches the inside pin and the negative touches the outer shielding. Also, I want to use a magnet-driven speaker rather than a piezoelectric one, would this circuit work with it? Sorry if I'm causing any trouble and thanks in advance.
Pnp transistors won't work in this circuit so that eliminates the 2n3906. For the other two all I can suggest is try it and see - and then let us know.
The antenna should be as long as possible, at least 40 to 50 feet for non-local radio stations. I pick up local stations using 3 parallel 15 foot long wires.
Since the electrons can go in only one direction through the diode, but when the cycle reverses we need some to go in the other direction, the high K resistor allows some, but not too much, to leak in the other direciton. I explain the same idea in my video about how a crystal radio works th-cam.com/video/HupFY_24o-4/w-d-xo.html starting around 2 minutes and 10 seconds in.
Ashok Nikumbh Do you mean the tuning bar/wiper blade on top of the tuning coil? That's for connecting to the tuning coil in different places in order to tune in to a radio station. You can see more about in in my video about making the crystal radio here th-cam.com/video/VqdcU9ULAlA/w-d-xo.html and my video about how a crystal radio works th-cam.com/video/0-PParSmwtE/w-d-xo.html
Yeah, sorry about that. Not having a formal electronics background and being heavy on physics I think in terms of electrons and protons and have a hard time thinking conventional current. I figure as long as I make clear I'm talking electrons then that should be okay.
Unfortunately it's not my circuit and I don't know the workings of all of it. There's a link to the person who gave me permission to use the circuit in the description below the video. I do know that the 82kilo ohm resistor can be from 10kilo ohm to 100kilo ohm.
Hi, Love your videos! Could you please tell me weather or not the crystal radio will work if plugged into a normal consumer amplifier and speaker instead of making this one?
Mymla Thanks! Glad to hear it! I've never plugged my crystal radio into a commercially made amplifier but I don't see whey it wouldn't work. I've seen plenty who've done it.
Could you please explain the exact purpose of the resistors and capacitors in the amplifier circuit. Why can't you just use the transistor+battery? Thanks.
+Stani I'm afraid I don't know what they're all for. I got the circuit from Charles Wenzel's website here www.techlib.com/electronics/crystal.html (redistributed with his permission.) It's under the heading One Transistor Amplifier/Detector.
The 1 uF non-polarized capacitors are hardto get. Instead, use an electrolytic (polarized) capacitor, any size is ok. Or use a 0.1 uF ceramic or whatever. The lower values may not have as much low frequency response, but that's ok for a cheap piezo earphone, which also has poor low frequency response.
That's a good point. It may be because the circuit may have been designed to also work with high impedance headphones with coils in them. The original circuit came from here www.techlib.com/electronics/crystal.html and though the diagram shows a crystal earpiece, the text below it speaks of a coil.
The output of this amplifier is less than a milliwatt. That's enough for a crystal earphone, but too weak for a speaker. You could increase the power with a few transistors, but it's easier to use an amplifier IC like the LM386. However if you're going to spend a lot of time and money, you might buy a cheap AM radio instead. The performance will be better.
some days ago I made an amplifier with only a darlington transistor (two 2n3904) a 100 kohm resistor at the input and a 1 kohm resistor with a 1 kohm potentiometer in series with the earphones. the load is on the emitter and the collector goes to the grounded pin of the germanium diode. the base goes to the other pin of the diode with a 100-1000 kohm resistor.the gain is very high (90'000) without the base resistor but without it the efficecy decreases. the amplifier consumes only 100 microamps with a 1,2 volts battery (120 microwatts). the sound is good but the selectivity of my crystal radio is really bad. if I move the capacitor I hear less sound but at the same radio station. (there is an AM transmitter at 5 km from my house and I hear only this station
if you cant build one get something like this www.activeforever.com/sonic-super-ear-se4000-personal-sound-amplifier you can remove the diode from your radio and you dont need a good ground hell mine picks up fm just remove the mic and attach if no sound flip
Your videos are simply the best I could find on the internet, keep up with your great work!
Another great video and really makes me want to order some stuff and start building circuits which i have not done since a was 13 yrs old. Cheers
Living in Ottawa, you probably even recognized the radio station. :) I'm glad you like it.
For that you'll need a different circuit. In the description to this video I give a link to Charles Wenzel's website. You'll find other amplifier circuits there.
Had to give you a shoutout. Really like your videos. You have a real knack for explaining these concepts in a way I never could. Ive incorporated many of the ideas from your experiments and some others ive seen online into my build, all the way from simple adds like the resistor + cap combo to get around the germanium leakage limitation on up to a small solar panel driven audio amplifier for a HiFi headset I use (a pair of Pioneer SE-500 piezoelectric HiFi headphones!). I started my first using two Michelob Ultra beer cans ... one sliced down the side and sheathed over the other with cooking parchment paper between ... similar to the concept of the foil one demonstrated here.
I didn't do that because it would make a very boring video for most people. Also, I was hoping I gave enough instructions so people could do it by following the circuit diagram that I show, for example at 2:12. But I guess if you are very new to all this it still may be difficult. So I will make a companion video with all the steps shown, but since I won't be able to do it for a week or two, see if you can do it by following the diagram and the basic instructions I gave in this video.
Thanks! I added them to the video's description. I assume since it worked you've answered your own question, that yes, you can use non-polar 50v 1uf capacitors. I didn't know you could get non-polar ones with that high a capacitance. I think that's the only reason polar ones were specified.
FETs, Field Effect Transistors are marked Gate, Source and Drain. The 2N4401, the one used in this video, is a bipolar junction transistor which used Emitter, Collector and Base.
Glad you like it!
As promised, I've made the video you asked for. See my latest video called "Steps for How to Make Amplifier for Crystal Radio Earpiece" that has every step shown where I put each part in the breadboard. I've put a link to it at the end of this video and in the description below this video or you can find it on my channel page. I hope it helps. -Steve
tom leroux just mentioned below that he had success with 2n3904 and 2n2222, so you're not limited to 2n4401. All I can suggest re the BC548 is give it a try. But let us know so I can add it to the list in the video description.
I use Sony Vegas Movie Studio but if you're referring to the part where I show different colored rectangles and red arrows overlayed on a photo of a breadboard, I created a bunch of separate transparent background GIF images of just the rectangles and/or arrows using OpenOffice Draw. Then in Sony Vegas I put the breadboard photo in one track and then put the transparent background GIF images one at a time in a separate track. Crude, but effective. I recorded the audio separately.
Yep man, for sure.
I forgot to thank you for sharing this.
U rock!
With it all spelled out like this, I'm sure you could build it. One step at a time. :)
The 100k resistor is the collector load resistor, and this should have about half the battery voltage across it. The current is about 1/20th of a milliamp or 50 microamps, which is so small that the battery should last for a very long time, maybe months. Yes, 82k is an uncommon value, so use 100k. How long should the antenna be? Thanks.
@1:14 I think that's what caused the time machine to go backwards in Back to the future? No no that was flux capacitor right! Man you are far more intelligent then I good sir. This is way beyond my understanding, but the result is pretty damn neat!
on the transistor will a 2n3904 or 2n2222 thay are npn type switching transistors and i got 2n3906 and thay are pnp transistors i have will one of them work at all
Glad to hear it! WARNING Crystal radios are addictive. :)
I don't see any problem with an RCA connector. Do you mean the old style magnetic earphones that people used to use with crystal radios before piezoelectric earpieces came along? If so I can't say for certain but I suspect they would work. You'll just have to try it to know for sure. Let us know. That also reminds me that I want to try and make a set of these magnetic earphones.
Thanks!
If you do make this, make a video and post here as a video response. Would love to see it!
I don't understand this circuit fully. It's one I got from the website I mention in the description. I would like to know it better! I know the 82kohm resistor and the 0.001uF capacitor are regular crystal radio improvements (see my new How a Crystal Radio Works video for those.) Also, a capacitor is often used in series to filter out DC. And the 10Mohm resistor may be for protecting the transistor's base. Without all that might work, but may not sound as clear.
yes the 2n3904 and the 2n2222 transistor works good
does it matter what kind a resistors or capacitors you have? or just the resistors: 82 kilo ohm, 100 kilo ohm, 10 mega ohm
capacitors: 0.001 microfarad, 2 x 1 microfarad, 10 microfarad.
thanks
Also another question, I want to use this amplifying circuit with say an RCA connection, so that the positive touches the inside pin and the negative touches the outer shielding. Also, I want to use a magnet-driven speaker rather than a piezoelectric one, would this circuit work with it? Sorry if I'm causing any trouble and thanks in advance.
Pnp transistors won't work in this circuit so that eliminates the 2n3906. For the other two all I can suggest is try it and see - and then let us know.
Why will this only work with 2N4401 transistor? Can it work with a BC548 (yes it is NPN)?
Thank you very much RimstarOrg
With the amplifier, yes it is. :)
What video editor did you use to make the breadboard scene with explaining how it connects ?
The antenna should be as long as possible, at least 40 to 50 feet for non-local radio stations. I pick up local stations using 3 parallel 15 foot long wires.
Thanks for sharing and easy explanation, can I ask, what’s the 82k doing?
Since the electrons can go in only one direction through the diode, but when the cycle reverses we need some to go in the other direction, the high K resistor allows some, but not too much, to leak in the other direciton. I explain the same idea in my video about how a crystal radio works th-cam.com/video/HupFY_24o-4/w-d-xo.html starting around 2 minutes and 10 seconds in.
can i use non-polar 50v 1uf capacitors
Don't transistors also come marked Gate, Source and Drain?
Hi, Love your videos! Could you please tell me what is the part that is shown in gray co lour in circuit near antenna coil. Thank you for sharing this
Ashok Nikumbh Do you mean the tuning bar/wiper blade on top of the tuning coil? That's for connecting to the tuning coil in different places in order to tune in to a radio station. You can see more about in in my video about making the crystal radio here th-cam.com/video/VqdcU9ULAlA/w-d-xo.html and my video about how a crystal radio works th-cam.com/video/0-PParSmwtE/w-d-xo.html
Ashok Nikumbh You're welcome. You can find my email address at the bottom of any page on my website rimstar.org
Yeah, sorry about that. Not having a formal electronics background and being heavy on physics I think in terms of electrons and protons and have a hard time thinking conventional current. I figure as long as I make clear I'm talking electrons then that should be okay.
Unfortunately it's not my circuit and I don't know the workings of all of it. There's a link to the person who gave me permission to use the circuit in the description below the video. I do know that the 82kilo ohm resistor can be from 10kilo ohm to 100kilo ohm.
Hi, Love your videos! Could you please tell me weather or not the crystal radio will work if plugged into a normal consumer amplifier and speaker instead of making this one?
Mymla Thanks! Glad to hear it! I've never plugged my crystal radio into a commercially made amplifier but I don't see whey it wouldn't work. I've seen plenty who've done it.
ok i will try it
Could you please explain the exact purpose of the resistors and capacitors in the amplifier circuit. Why can't you just use the transistor+battery? Thanks.
+Stani I'm afraid I don't know what they're all for. I got the circuit from Charles Wenzel's website here www.techlib.com/electronics/crystal.html (redistributed with his permission.) It's under the heading One Transistor Amplifier/Detector.
+RimstarOrg Thanks for the link. :)
Base Controls the flow between the collector and the emitter.
Isn't that what I say at 5:08? Or are you referring to something else?
You say from "emitter to collector" or "between emitter and collector" ... its semantics though, electron flow versus hole flow. Who cares.
What is the point of all the resistors and capacitors? Couldn't it work with just a transistor and a battery?
The 1 uF non-polarized capacitors are hardto get. Instead, use an electrolytic (polarized) capacitor, any size is ok. Or use a 0.1 uF ceramic or whatever. The lower values may not have as much low frequency response, but that's ok for a cheap piezo earphone, which also has poor low frequency response.
Can we use other speaker
Yes, if the speaker has its own power/amplifier. I made a homemade one here th-cam.com/video/U5axWtCqgCA/w-d-xo.html
I just follow instructions well :)
I have a feeling that it draws a very low current. Do you know how much exactly?
No, I never measured it. But I'm pretty sure of the same thing, it's a very low current.
I was initially confused by the direction of green arrows. @ 5:17.
Then I paused and saw the little key in the bottom right corner.
Why you need a 1mf cap in series with the earpiece when it is a DC blocker itself?
That's a good point. It may be because the circuit may have been designed to also work with high impedance headphones with coils in them. The original circuit came from here www.techlib.com/electronics/crystal.html and though the diagram shows a crystal earpiece, the text below it speaks of a coil.
i got them out of old junk radios i had goten over the years the non polar caps
I "studied" all about electrics, but don't know how to do nothing like that...
Too lazy to make it.
Someday I will win the inertia lol
The output of this amplifier is less than a milliwatt. That's enough for a crystal earphone, but too weak for a speaker. You could increase the power with a few transistors, but it's easier to use an amplifier IC like the LM386. However if you're going to spend a lot of time and money, you might buy a cheap AM radio instead. The performance will be better.
First reply to first comment! :)
some days ago I made an amplifier with only a darlington transistor (two 2n3904) a 100 kohm resistor at the input and a 1 kohm resistor with a 1 kohm potentiometer in series with the earphones. the load is on the emitter and the collector goes to the grounded pin of the germanium diode. the base goes to the other pin of the diode with a 100-1000 kohm resistor.the gain is very high (90'000) without the base resistor but without it the efficecy decreases.
the amplifier consumes only 100 microamps with a 1,2 volts battery (120 microwatts).
the sound is good but the selectivity of my crystal radio is really bad. if I move the capacitor I hear less sound but at the same radio station. (there is an AM transmitter at 5 km from my house and I hear only this station
Do you have any schematic of it? I'm really interested in the amplifier that you made.
wow :)
FIRST COMMENT?
Wenn der Ohrhörer 🎉 manchmal nicht funktioniert kann man einen 3,3kohm Widerstand parallel schalten.🤐🙄💖heisser Tipp vom alten Detektor Freak.
if you cant build one get something like this
www.activeforever.com/sonic-super-ear-se4000-personal-sound-amplifier
you can remove the diode from your radio and you dont need a good ground
hell mine picks up fm
just remove the mic and attach
if no sound flip
buy a new mic pls the s sounds are horible