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- เผยแพร่เมื่อ 26 มิ.ย. 2024
- How to make a robust crystal radio. DIY step by step. No special tools or skills needed. Most parts can be had from recycled things. The purchased parts run about $3. Good during power failures, when batteries are not available, for prepping and similar.
Updated Video: Best/Easiest DIY Crystal Radio - No Batteries, No External Power 2023 (4K)
• Best/Easiest DIY Cryst...
Depending on your design (coil mostly) it can receive in the AM broadcast band, approximately 535 to 1700 kHz.
See Warnings below.
This one is loosely based on the Cub Scout / Wolf Scout / Boy Scout crystal radio design.
OPERATION TIPS & TRICKS
- A good antenna is important. Longer is usually better (see antenna warning below), a good ground is next most important. More below
- With some stations, you can put a finger or 2 or 3 inside the tuner coil to improve reception. Move them around for best reception.
- A finger near the coil can also improve reception. Touching the coil directly usually lowers sound volume, BUT a piece of paper or thin plastic between finger and coil often improves sound / tuning. Move finger around.
- Touching different parts of the radio or getting near them can affect performance.
TOOLS
- Screw driver
- Knife
- Sandpaper (small piece, fine)
- (Optional) Saw, if you do not have the wood & tube already cut
- (Optional) Hand drill for screw holes
- (Optional) Soldering iron, solder
MATERIALS
- 1 x Germanium Crystal Diode (1N34A)(bought: Amazon, Radio Shack 276-1123, Digikey, Jameco, Mouser...)
- 1 x Resistor (10k ohm, carbon, not wire wound)(bought: ditto)(see note below)
- 1 x Crystal earphone (can NOT be other type)(bought: Amazon, Jaycar, Jameco?) MUST be like the type in the video. Regular iPod or similar will NOT work.
- 1 x Base 21 x 17.5 cms x 2 cms thick or more (wood scrap)
- 1 x PVC pipe 15 cms long or stiff cardboard tube x 2.5 inch diameter
- 1 x motorcycle / bicycle spoke, 2mm diameter or brass rod or stainless rod
- Enameled bell wire (can be from old transformer, solenoid, ...) 0.3 to 1.5mm (note: I used 0.5mm or roughly 19-20 AWG, the number of turns and length of pipe change with wire size.) Bigger wire has lower resistance (better sound), BUT you get fewer turns per centimeter (less tuning).
- Screws, stainless or brass (6 for wire hold downs, 2+ for coil mounting),
- Fahnestock clips (6) (bought: Amazon & electrical shops). OR brass washers (13) (bought, hardware store)
- 2 bigger washers for wiper.
- 1 bigger, large head screw for wiper.
ANTENNA & GROUND
- The antenna is just a long piece of wire (I use scrap wire from old transformers, fluorescent light ballasts and such). The longer the better.
- Try different lengths and orientations (vertical, horizontal)
- A good ground helps. A wire to a ground rod is good. Metal water pipes also work well.
NOTES:
- I ran the calculations on the coil and with 2.25 inch tube and 170 turns it's about 425 micro Henries (but it varies up to 650 depending on whose calculator I use). That's a bit more than the typical design which runs about 350 - 400, but still very workable. It means you can get by with more like 150 turns of wire.
- The resistor is necessary to get the best sound from these "new" crystal earphones. The new ones are piezoelectric and have lots of capacitance. Without the resistor the charge builds up then discharges so you get constant "static" sounds. The resistor bleeds off charge so you get louder, and much clearer sound.
- Also called a foxhole radio.
WARNINGS:
- Never connect radio to any source of power. Not house current, nor batteries, nothing!
- Never use the radio during lightning storms.
- Never run an antenna over or near power lines.
- Disconnect antenna when not in use.
- Never ground to electrical items, plugs or similar.
- If you don't know, don't do it.
OTHER:
An excellent website by an avid and skilled builder:
www.lessmiths.com/~kjsmith/cry...
INTERESTING LINKS
Air Core: www.circuits.dk/single-layer-a...
OTHER CRYSTAL RADIO VIDEOS
- Best/Easiest DIY Crystal Radio - No Batteries, No External Power 2023 (4K)
• Best/Easiest DIY Cryst...
- A comparing 2 designs, one better than the other
• Popular Crystal Radio ...
- Crystal Radio Powering a Joule Thief
• Joule Thief PLUS Cryst...
- Popular Crystal Radio Design That Does Not Work
• Popular Crystal Radio ...
- New Crystal Radio Design
• New Crystal Radio Design
- World's Simplest (Crystal) Radio
• World's Simplest Radio
- Crystal Radio Improvements & Upgrades
• Crystal Radio Upgrades...
- Putting a Wood Knob On a Shaft
• Mount A Wood (or Metal...
- Connect DC Amplifier to Crystal Radio
• Connect DC Audio Ampli... - แนวปฏิบัติและการใช้ชีวิต
Updated Video: Best/Easiest DIY Crystal Radio - No Batteries, No External Power 2023 (4K)
th-cam.com/video/fLVCqZGpv3U/w-d-xo.html
RELATED CRYSTAL RADIO VIDEOS:
My New Favorite! Crystal Radio with Antenna Tuner: th-cam.com/video/mh5KxCpbQ5U/w-d-xo.html
Crystal Radio & Resonant Coil Design: th-cam.com/video/Fw9eb-aB-XU/w-d-xo.html
Crystal Radio Antenna (Shortwave Also): th-cam.com/video/G8AsgZbncW4/w-d-xo.html
Crystal Radio, Capacitive Tuning - WORKS GREAT!: th-cam.com/video/VJ80Nm9KSkE/w-d-xo.html
Good Crystal Radio Connection Points: th-cam.com/video/G3qjrReHR1k/w-d-xo.html
My Crystal Radio Does NOT Work (FIXES for common problems): th-cam.com/video/kCxQ8iPQx4s/w-d-xo.html
Crystal Radio, Connect A DC Audio Amplifier: th-cam.com/video/RW3VhnzgjtA/w-d-xo.html
Connect DC Audio Amplifier To Your Crystal Radio: th-cam.com/video/HOw3yDFXXN4/w-d-xo.html
Three Upgrades For Your Crystal Radio: th-cam.com/video/LENco3_jV_s/w-d-xo.html
Crystal Radio Wiper Upgrade: th-cam.com/video/i1otDz39nlw/w-d-xo.html
Popular Crystal Radio Design That's a Waste of Time - And Why: th-cam.com/video/r9Onub2Xpzc/w-d-xo.html
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I had one of these in the 1950's when I was a kid. My bed was next to a window, and I ran a wire outside the window and wrapped it around a screwdriver I stuck in the ground. I used the window screen for an antenna. I would then lay in bed and listen to The Fleetwoods and The Coasters. With the ear plug my parents thought I was asleep. There is nothing like listing to "Dream Walk" by Santo and Johnny at 1:00am on a summer's night.
I used the gutter of the house for an antenna and used to listen to baseball games when I was supposed to be sleeping. Good times indeed!
Made one when I was 10, from a kit. Wound the wire, etc. Had a small antenna wire, could pick up local stations. Outside my bedroom window was a sycamore tree, about 30 feet tall. Ran an antenna wire about 20 feet up the tree. I could pick up Mexican radio stations at night. Pretty cool stuff.
I love these guys who are trying to learn the world something. Only a shame that the final demonstration, there where the magic starts to happen, is so short.
He mentioned in another comment string that he originally put some off the air audio into his video and he got a notice from TH-cam to remove it. Apparently putting off the air content on TH-cam is a potential copyright violation.
@@joevignolor4u949I used to make these radio crystal radios when I was a kid back in the 70's. Pretty sad that TH-cam has nothing more important to worry about considering some of the things on it. What a f'd up world we live in.
TH-cam and the rich people doesnt want you to know that it is possible to get such a clear sound from an energy free radio or else the business goes down
I built a crystal radio with my dad when I was about 8. He had one in the army and he strung the antenna on the clothes line outside the barracks so the sergeant would not notice it. My antenna stretched out my window and across the back yard. It was a circuit with a variable capacitor for tuning and I loved to tune it to different stations and hear music and talking from all over. We were near enough to Canada to get French stations which to me sounded so foreign and mysterious! To this day, I fall asleep with one ear bud in my ear listening to Podcasts.
Brownie - a trick I learned once was that you could make a diode using a safety pin and a quarter. You screw the clasp of the pin to the board so that the elbow sticks up in the air and the point comes back down onto the center of the quarter, held there by the spring of the pin. The surface effect makes it somewhat of a diode at higher frequencies. You can hook the wires by twisting one onto the pin clasp and the other underneath the quarter. You might try this on your kit there. Someone below mentioned a similar trick with a razor blade and a pencil lead.
Thanks for the cool video and the wonderful memories!
Thank you for your stories. I've not heard of the pin and quarter, will have to try that. I used to use galena (lead mineral) and a pin, but now I'm lazy! ;)
I remember getting a crystal radio kit as a Christmas gift when I was 8 years old. If my memory serves me correctly, the tuning-coil came pre-wound, so I didn't have to fart-around with that.
It came with a very long antenna, that my father ran from his bedroom window, all the way to our clothes-line pole in our back-yard. (Unfortunately, my own bedroom window faced our front-yard.)
After its assembly and antenna connection, it received most, if not all of the local AM stations clearly; mind you, at that time, I lived in a small city of approximately 100,000 residents, so there weren't many stations to receive. I had a lot of fun with it, nevertheless. :)
3 things will cause your crystal radio to NOT WORK. 1. You must have a long wire for an antenna. 2. You must connect the ground to a good metal water pipe or other metal going into the ground. 3. you must use a PIEZO or CRYSTAL earphone.... not one of those modern magnetic wire earphones. Also be sure to scratch off the enamel paint on your copper wires AS HE explains in his video. I made one of these in the 5th grade back in about 1965
Magnetic headphones work fine if the impedance is 2k or higher. Of course these are not widely made anymore, and the modern 4-32 ohm impedance won't work at all, UNLESS you also use a matching audio transformer such as the Bogen T725.
What if you can't get those earpieces ?
@@QIKUGAMES-QIKU you can use a amplifier
Cool! I got a crystal kit for X-mass in 1962 and my dad who knew all about them kept telling me it will not need batteries to make run as we put it together. I thought it was all a joke and was waiting for the gotcha as he had be put the ear phone in my ear and ta da ! WSB am came it clear as a bell. Tuned it a little and WQXI came it too. I will never forget this and wish I had a picture of the look on my face as I heard my first crystal radio work.
+ufoengines Thanks for the comment. I made one out of the boy scout book and was also amazed it could work. I guess EverReady had us all brainwashed. ;)
Nice build. I made one of tgese with my grandfather in the 80s, he made one as a child in the mid 30s. It was a great memory for both of us. Ultimately, building this simple am crystal set with him sparked a lifelong interest in electronics. I went to school for electronics engineering, but ended up only working in the field for a few years. Still love to see people build cool things and watch the amazment of children at mnaking suchva seemingly complicated thing with so few parts. Everyone should build one, just for the experience.
Me and my pops built a crystal radio like such back when I was a kiddoe, I always found the concept fascinating
When I was a kid My brother made a crystal Radio and I was amazed. I always think these kind of projects can come in very useful if your'e in a situation like war or somrthing like that.
Great video, very informative, thanks. FYI, POWs used to make these to hear 'the truth' about the war. It gave morale a huge boost!
Dave Leland I would love to know how they sourced the Parts, I personally knew 3 extremely Senior Pows and spent time with them over the years talking about being in the Hanoi Hilton, I never herd one mention a crystal receiver. Two of them were hams also. Just saying!😁🛫
@@TheFalconJetDriver Well, I don't know about your 'senior POWs' or the "Hanoi Hilton", BUT this is the information I have... en.wikipedia.org/wiki/Foxhole_radio, hackaday.com/2016/04/21/hacking-when-it-counts-pow-canteen-radios/, www.radiosurvivor.com/2009/07/06/home-brew-radio-in-a-wwii-pow-camp-shows-radios-survivability/. So you see I think I have reliable information that they did BUILT them in the POW camps.
My dad had one of these when he was a kid and listened to the Grand Old Oprey on Saturday night.
Wow, I really wanted to hear you tune in at least a few stations after that lengthy build lesson.:-)
Me too. In video version 1.0 I did that and youtube sent me a take down notice.
tsbrownie why?
@@morphenominal Copyright violation probably. It's getting so bad that you can't even pass gas without YT says you violated some copyright or something. :)
@pjd412 They are ultra-safe when it comes to protecting themselves. I can't afford the time to re-do things they take down then force me to prove it's "fair use". And they won't review it until it gets thousands of hits, so once burned, many times shy. Oh, and if the copyright owners complain youtube gives them 100% of the few dollars I get for a video, now the owners want 110% of the take.
@@dleland71 yep, YT is so inconsistent... porn, full movie and TV show videos stay up but a little bit of an am radio broadcast to illustrate how this radio works? CEASE AND DESIST!!! Ridiculous....
Excellent, thank you for sharing your knowledge.
You are welcome.
Great job. Amazing how simply these radios can be constructed and still work pretty well. This is exactly how I started with crystal radios and then eventually went to double tuned "tuggle" type tuners, and sound powered phones. I am currently into large loop crystal radios which don't use external antennas or grounds and can be seen on my channel. Keep up the good work!
We used to build these when i was about 7 years old and now maybe with this video todays generation can experience the same magic that I had as a child.
This is the best how-to crystal radio I have found on youtube. Thanks for the clear and concise instructions!
Aghast Thank you for the compliment!
The time has come for those who has knowledge, wisdom and information about how to do. they will go far away with respect to those whose every day passing same. thanks for sharing this info about how to make a free radio (; I am a new subscriber now
Very well done ! Your explanation was spot on. Thank you for sharing.
All the best.
Bobby
I knew a guy who built a radio powered crystal set. He used the rectified dc power from a strong station (WMAL) to power a germanium transistor and a 12" speaker. Very clever invention.
I was 6 or 7 in the1950s and my dad had the how to build one out of his Boy Scout manual. I don't have any idea how old the Scout manual was. I loved this back then it was a s great as X box is today. Thanks for bringing back great memory's.
I too had good memories of building one of these "magic" devices and it turns out there are a lot of us. I'm glad I could help bring back recollections of those good times.
Wonderful instructions my dad made radio receivers for fun my kids not too so. What a great simple receiver. Thanks
to tsbrownie; I just completed 25 kits for a class to assemble your radio design. I posted a question earlier and the prototype worked great. Thanks again for an elegant simple design that works! We are thrilled.
Glad you found it useful. Thanks for the feedback.
I still like playing with a crystal radio. Built my first in the 1970s. It was magical to listen to radio stations by connecting the antenna to a pipe. It is still magical. I built a shortwave version several years ago.
I agree. It is magical. People I show it to, from engineer friends to my son's science teacher are amazed by it. It's like getting something from (almost) nothing.
I have watched a lot of videos on the fox hole radio this evening and yours was by far the coolest one. I'm going to use your design for sure. Thank you.
Thank you. Let us know how it goes.
I built a number of these in the 50s. A couple of years ago I even picked up a few galena pieces at a rock and gem shop to do it again. That modest beginning led to a full career in electronics.
It is awesome!! Thanks for showing how to make a simple radio.
You did a great job! When I was a kid a guy that worked with my dad built a radio like this and I remember he used an old spice deodorant stick to wind the coil. I wish I had asked him for it, those were the good ole days.Thanks again, I might build one myself.
Thank you. Old Spice tube, that's interesting. You should build one. They are not hard or expensive. Let me know how it goes or if you have questions.
Exceptional video. Simple to understand, clear and concise explanation. Thanks for taking the time :O)
+sandpiper9988 Thank you!
Amazingly simple..i can't wait to make one for myself!
Let us know how it goes. There are 2 critical parts that can not be substituted: earphone and diode. They must be exactly those specified. And outside of that, if you are within 100 kms of an AM station it's pretty much a sure thing.
I'm in school for robotics and this never crossed crossed my mind even after watching mythbusters do a similar project! this is your first video I've watched and im subscribing hope you continue to make innovations to inventions
You don't need to burn power on a downlink! ;) Kind of like RFID.
God bless tsbrownie for being so patient in answering the same questions over and over. This is ancient technology(over 100 years old) that obviously works. Follow the instructions and it will work. No it won't pick up FM or short wave etc. If you have an antenna, a ground, a coil, a diode and headphones it will work. It's like a miracle you have built with your own hands. Try to appreciate that miracle. No it won't blow you away with fidelity and volume. It is what it is. A good antenna and a good ground are important. In a darkened room you can strike the antenna and ground wire together and see a spark....or put both wires on your tongue and feel the electricity you are capturing from the air. Follow the instruction in the video. In fact, I have made some down and dirty(quick and ugly) versions that also work. Forget the overkill about spring clips and screws and washers...just strip some insulation from the ends of the wires and twist the wire ends together to make a connection. I'm not advocating sloppy craftsmanship...just saying...if you get the connections made, it will work. Appreciate it for what it is.
Never knew they would spark. Cool! Have to try that. Thanks!
That thing is really nice. Bomb proof.
They are tough and pretty much foolproof.
Nice video. Thanks! More theory would have been really helpful, though. You went into deep detail on the easiest part (assembly), but I would have loved to hear more about what each component actually does.
Wow! cool video,when a was young,i receive a kit of radio cristal but he never made a single noise but now i m gonna build one like your's and it gonna work!!thanks for your expertise!
Please watch my video on antennas. You also need an AM radio station in your area. And it gonna work!
Damn those coil wrapping skills!!!
I'm working on a new one that has only 32 turns. It's a lot easier!
I want to help my 12 year old grandson how to make a crystal radio, I have a Philmore VC1000 that and uncle gave my when I was 10 years old (1966) we put it together and strung bell wire all over our 1 acre yard trying to make the best antenna I could. A neighbor gave me a two pieces of u channel aluminum one 6 feet tall the other 4 foot. I made cross with them and screwed them to a skinny Poplar tree in my back yard about7 feet off the ground and that became my antenna and it worked well. I sanded the aluminum and cleaned the copper 23 awg bell wire ran a screw around the wire and the aluminum and I spray painted it with enamel paint for corrosion protection.
In 1976 my parents moved from that home. In 2018 I visited the area where I grew up. The aluminum antenna parts were 60 feet in the air to my knowledge it is still there. Of course the bell wire is long gone. 😁🛫
This is the best of the easy designs. Let me know if you have questions.
Great instructional vid. Thanks for sharing.
Thank you. This is the new and updated version.
th-cam.com/video/fLVCqZGpv3U/w-d-xo.htmlsi=iXN2sxawUr4UdWn4
built one of these as a kid in the 60s. Toilet paper roll, wire wrap, crystal, diode, and the earpiece
Me too. This is just an updated version of what was in the Wolf Scout handbook.
Very cool! Thanks for making the video!
Thank you. Let us know how yours works.
I saw the earphone needs to be like yours in the description .Thanks You.
La de da! still amazing how this old tech works.
Very good detailed video.
When I was 12 I made one using a 1N34A diode ,a 400 microfarad capacitor. The coil was a 5 inch 2x2 wood block with the corners rounded off in a lathe. I used the lathe to wind the wire on the wood . sprayed shellac on it to keep the wire coil together Mounted the coil with 90 ° metal corner brackets at each end so that one corner of the coil was on top. the wiper was a piece of galvanized metal strip with a copper wire solder along the length of it . mounted on a block of wood level with the top of the coil.
the most important part was the antenna..I used 200 feet of wire strung between the house and a power pole on the other side of the neighbor's yard.
the antenna will be more directional in the opposite the end picking up stations that way.
if it goes east to west and if end is west of your radio stations east of you will be stronger.
The old crystal earphones required that 400 uF cap to work. The new crystal earphones are actually piezoelectric and come with a lot (almost too much) capacitance built in so that's no longer needed (in fact it keeps the radio from working). Sounds like you did a very nice job on building it.
Thanks for sharing! I've made this one too! It works!!!🌞🌍👍
Thanks for sharing. Keep us posted.
It might make it easier to wind the coil if you put a piece of double face Scotch tape down the length of the form, maybe even two on opposite sides of the tubing. Also, a spot of hot glue to secure the ends to the form when you are done. I built my first one about 65 years ago as a Cub Scout.
That's a clean radio ,well done ,now if someone could make a apartment crystal radio ,that would be cool for me ,I got all the parts ,except after seeing your video ,I no now I need to buy some brass washers and brass screws,and I going to buy heaver that's megneti c wire i think it works better and looks better too ,some of your ideas work for me ,I like soldering things together,when I can ,I no it makes a better connection.thanks for letting me barrow some of your ideas.
This knowledge is important to have because you can never know what circumstances may be in the future. You may
find yourself having to MAKE this because you have no alternative. Remember, radios have been CONFISCATED by
authorities in the past.
thanks for your knowledge too!
listed to waterloo Iowa when I was a kid on crystal set.
I always thought all devices made are impossible to make without a circuit board or advanced tech. This has got be the simplest one done! From scrap to finish. Radio that runs without battery or electric power! I would love to see it tune more frequencies. Gratitude!
Hello jaz
I've uploaded videos
I have a small apartment in Bishkek kyrgyzstan
And a simple crystal radio
Just click user name
A 'Macgyver' radio, always useful!!
Mid to late '50's KIX cereal had them for I think two box tops & $.50 and they sent you in the mail. I remember it came with an alligator clip which all you had to do was ground it like the center screw of an outlet cover or the finger stop on rotary phones. The good ole daze!!!!! It was 2" long and like 3/4" square. Came with an ear piece.
Sandpaper for the enamel works best with some grit to it. Neat trick my father taught me
Nicely done vid and radio
Great stuff! - reminds me of the one I had ~60 years ago!
I built my first one about 54 years ago. It was like magic.
@@tsbrownie Yes, that is what it was like for me too - I was living in Sydney (Australia) and I distinctly remember staying up really late to listen to a Rugby League (football) "Test" match that the Australian team was playing against England . . it felt like being in the French Underground listening to a broadcast from across The Channel . .
@@PhilipRhoadesP I can relate. I used to listen to baseball games on my crystal radio when it was past my bedtime. I had used a battery powered radio, but I'd fall asleep and the batteries would go flat and I didn't have money to buy more.
I had one in the early 1960’s. I think it was something I got off of the back of a cereal box. I’d listen to Cincinnati Reds and Royals games on WLW at night.
Don't tell my mom, but I used to do the same, but it was Chicago. Do you mean the KC Athletics? ;)
@@tsbrownie no. The Cincinnati Royals was an NBA team. Oscar Robertson was their point guard before they traded him to Milwaukee.
Love your video the best one I've seen thank you .
Thank you!
thank you that was well presented.
Well Done. I think i will give it a try. I may just try to purchase one all ready made , the coil may be the problem for my 75 year old hands.
I won't lie to you, the coil is the hardest part. Keeping it tight and "beautiful" helps, but it will likely still work. Maybe you can find a relative or neighbor? These radios are almost magical. Oh, and the antenna is important. It can just be a long wire (stay away from electric lines for safety and to prevent buzzing) running parallel to the ground. I use wire from an old transformer.
VERY EASY INSTALLATIONS I WILL MAKE ONE WITH MY GRAND KIDS
Let us know how it goes.
This is amazing! I've been thinking about building a low cost v2 crystal radio, (I've built from a kit before v1), I'm going to build one from your demo, I'll post results..
Thank you!
Look forward to it.
just came across your channel and am truly amazed .
Sir if you don't mind could you post another video of just listening to your home built radio .
I'm looking forward to building my own and learning more in how it works .
Thanks again for this video .
Thank you. I can not play what is on the radio because under US intellectual property law, that is not allowed, and youtube will take down the video.
thank you it was very helpful
Fantastic thank you kindly
Very welcome.
Try double sided tape along the PVC before you start the winding. It won't be too sticky, but it will help hold the wire into place. Thank you for such and interesting and informative video! Most people don't know about this kind of thing.
The thin stuff would probably work. I was always concerned it would make the surface lumpy.
Great video! Thank you for sharing your skill & knowledge.
Fantastic! Thank you.
Glad you liked it.
great i will bulid one Thanks!
That's super cool, thanks, I hope never but just in case it's a grate idea
It worked well.
You picked up Radio India by the sounds of it.
LOL
Awesome video! Great description! You sir deserve a thumbs up!
Thank you.💚
Thank you for dropping by.
thank you very much 👍👍
If you build one, let us know how it goes. Leave a comment if you have questions.
this is great! i am going to build one just like yours. Could you also in your next video put another presentation with a 10watts amplifier, even if it is two or multiple stages will do. I want to build this with two stage mono or stereo amplifier with 10 watts of power max. Thank you for the video.
Thank you.
this is very cool
Anybody remember razor-blade radio receivers using a Blue Gillette blade? The device was shown in a 1950's Superman annual. I could also pick up "The Third Programme" transmitted by The BBC by clipping a pair of headphones to the hot and cold water pipes in the airing cupboard.
happy plucker I built one in the late 50s.
@@dwighthebert4052 First published in Superboy #6 (1950) ...
What a great video though thanks for sharing!
Thank you. Glad you liked it. I've got a couple more videos on good crystal radio designs (and a few on ones that don't work well!)
Or for added realism use an actual crystal. I bought two in metal boxes, Hertzite and Cymosite and one in a cardboard box, a Dr. Cecil. You might find them at radio rallies as I did with Dr. Cecil or smaller electronic shops where I got the the other two. The Dr. Cecil came with a small piece of gold coloured wire. Wrap the xtal in tin foil leaving the xtal exposed on top and attach a wire to the tin foil, then fix a stiff wire onto a sewing needle and attach the other ends as shown in the video. By probing around with the needle a sensitive spot can be found and stations heard. It works but is tricky. The old sets had an arm to adjust the spot and hold it there.
I like this kind of stuff. Thanks for showing it tsbrownie.
It was only later I made a crystal set after starting with a one valve kit, H.A.C, Hear All Continents aged 13. I later made mullti valve sets in my teens, moving onto transistors then i.c.'s. Got the amateur licence and made my own h.f. tx/rx. Took thing back a few years ago and made a one valve transmitter using a crystal.
Bill, G4GHB.
I remember reading somewhere the special wire was phosphor bronze and 'Wood's Metal' used to hold the crystal.
Bill, G4GHB.,
I looked it up. I wonder if just lead would work. Galena comes from around lead mines.
Bill.
I used galena on my first radio and it does work, but now I'm lazy and use the diode. It is less fussy! I should do a demo of it.
The old cub scout model that I first build had you cut a piece of 1/2 inch copper pipe to put a mount tab on the bottom and a set screw in the side. It worked.
@@tsbrownie Yes, that would be good to show, and how tricky it is.
I remember building one back in 60s only instead of a crystal we used a razor blade and peice of graphite pencil lead
I remember doing the same lead . . . . . empty toilet paper roll with about 120 turns of #24 bell wire with graphite from a pencil over the razor blade to tune !!!
I would like to see that. Have you built one recently or do you have a diagram?
I used a 1n34 crystal diode.
there are numerous detectors possible.
1n34, oa91, aa143, FO-215 or similar germanium diodes.
modern shottky diodes; 1n5711, HP5082-2835, HSMS281.
even some minerals form "diodes" with cats whisker (point of graphite, copper, silver), Galena (lead sulfite ore), iron-pyrite, magnetite, copper-pyrite, calcopyrite (peacock ore), zincsite, stenite...
Rusted nail, tarnished ccopper or silver, blued steel (gun barrel, razorblade...).
Here are more
crystalradio.net/minerals/index.shtml
www.crystal-radio.eu/endiodes.htm
As kid I made a razor blade detector with a sewing needle. It worked but was not dependable like a diode was that was about 1965 in Chesapeake, VA
Excellent!
+Highlander Movie Thank you!
It will work for the foreseeable future. With MW stations moving off and others just going dark MW probably won’t be around in the next 40 years.
You can dispense with the diode as they may be hard to find, you replace the Diod with a safety pin and a razor blade.
good technology
When I was just a wee lad, we made crystal radios, but it seems to me that we actually used a crystal then a brass pin to connect to touch the crystal. But basically the same way.
This is a modified version that was in my Wolf Scout handbook. (They had a mistake in the drawing that kept it from working!) We used a piece of galena (lead ore) and a brass safety pin as well. The diode is much more reliable and gives a clearer output.
Nice
THANKS
And thank you!
I built a crystal radio from a kit i bought at radio shack when i was a teenager that thing not only picked up AM but Shortwave as well my father told me it was because shortwave is an extension to AM
Your father was correct. AM is used in both broadcast bands and in shortwave.
Thx I'm building one myself
Let us know how it goes.
The first crystal radio kit I got was a X Mass gift from my dad in 1962 and when we / he assembled for me I was astounded that it worked without batteries! Even in 1962 every kid knew that cool toys and radios needed batteries to work so this gizmo was too super cool! Later from time the Walgreens Drug store would sell near the check out the Rocker Radio ! for your listing pleasure or about $3.95 in 1965 money. th-cam.com/video/t5ww6bQg5ic/w-d-xo.html . I bought a couple but my peers though it just make look like a nerd when I was using it so I gave up on them and they ended up lost or broken . Still love the idea of this very old tech.
I built my first one about 4 years after yours. Mine was from the Wolf Scout handbook. Did not work at first. By trial and error I figured out there was a misprint and an extra wire was shown that shorted the main coil. Still have that book. It was a lesson to me that books are written by people and people make mistakes.
to many complaints that it doesn't work. Morons! it does at 20:51 to 20:54 you didn't bother to wait till the end. no patience. i made one in 7th grade 1975. Thumbs up. i Like, OLE!
Mahalo for sharing!
awesome
thanks
tHANK YOU!
Realy clear. I receive you Five on five:)
Eric
Outstanding demo !
Outstanding demo !
Awesome. Very easy to understand this. You are the master explainer! I have a question about the coil used for tuning. Is it a variable capacitor or what manner of component is that? All good wishes.
+Anton Nym Thank you very much. That's a good question. Most people think of the coil as an inductor, but in fact it also has significant capacitance. In this model when you move the wiper you are making 2 changes: on the left you are changing the inductance / capacitance with the antenna, and on the right side you are changing the inductance / capacitance of the tank (resonant) circuit. For example: if you move the wiper to the left, the antenna side inductance and capacitance gets smaller, while on the right side (tank circuit) the inductance and capacitance increases.
My mother had a friend who was stationed in Burma during WW II. He said that the soldiers who had new or newer rifles would use a section of the barrel that had good bluing for the detector section instead of a galena crystal and cat's whisker or the germanium diode used today. Obviously not during battle. Some would use Gillette super blue razor blades. The bluing on both, when dry, forms a conductive crystal structure that can exhibit semiconductor properties. I don't know if today's gun barrels are coated chemically the same way that they were 80+ years ago though.
Another setup, he said, was instead of the coil wiper, they would whittle some of the wood back off the end of the end of a pencil, twist the wire tightly around the graphite pencil "lead" near the wood and use the pencil point as the detector / wiper, again, replacing the diode. Graphite also has a crystalline structure that can exhibit semiconductor properties.
Before the late 1950's There were no semiconductor diodes or transistors. Regular radios used vacuum tube diodes as the detector. Soldiers had to get creative if they wanted news or music in their down time and the above is what some came up with.
I was born and raised in downtown Rochester N.Y. 5 miles from the hill where the bulk of our radio and TV transmitters were. Crystal radio reception was LOUD AND PROUD to say the least. One time, using an AM radio tuned loopstick antenna, for those who don't know, it is a factory wound, center tapped coil of wire about 2 1/2 inches long and a little wider than a pencil with a ferite slug inside with a threaded rod molded in to screw in and out of the coil. Rather than using a wiper on a bulky coil to tune the radio, you would solder a 100 pF disk capacitor across the 2 outside contacts, connect the germanium diode to one side, connect the antenna to either the same side as the diode or the center tap, which ever works better, connect a 50 pF disk cap across the open end of the diode and the coil contact opposite the diode then your crystal earphone across the 50 pF cap. Connect the ground to the coil contact opposite the antenna. Screw the ferite slug in or out to tune.
The radio above I experimented with a bit. Instead of the 2,000 ohm earphone, I connected a 2,000 to 8 ohm miniature audio output transformer and speaker out of a pocket transistor radio. I mounted the whole circuit on a small piece of perf circuit board and put it in a cassette tape box. Being 5 miles away from a 5,000 watt transmitter, I had to install a volume control on the transformer to cut down on distortion and volume enough to understand speech and music. I didn't actually need an antenna but the only thing keeping it from being a truly portable radio was the need for a good earth ground like a water pipe or the 3rd prong of an electrical outlet. It was loud and clear enough to set on a dinner table for anyone to hear. Where I live now in West Virginia, the nearest AM radio station is 28 miles away so this circuit wouldn't work here. When my son was young, we built basically the same circuit but using the crystal earphone. 50 feet of wire strung in the trees bought us only static. He got a kick out of trying though.
Thanks for the comment. Lots of good stuff there. I have to try the pencil and razor blade things one of these days.
I'm sure the pencil thing would still work but I don't know anyone that still makes blue blades anymore. With the advent of 137 bladed razors, I don't even know if you could get double edged razor blades outside of an antique shop. Maybe Amazon or E bay? If you do locate some, they can't just be blue painted. The bluing that they used to use on guns and razor blades was for rust prevention so you may have to try an antique shop for the original Gillette super blue blades. The area of the blade that you want to use can't be rusty so be aware of what you are buying. Other companies may have made them but the old Gillette TV commercials sticks in my mind. getting senile I guess.
Also, with the pencil thing. If you don't get results the first try, try different hardness of pencil lead. Number 2, 3, 4, 5 up to drafting pencil lead. Pencil makers add clay to their lead formula to control hardness. Number 1 and 2 are soft and usually required for lottery ticket computer read order slips, multiple choice tests and such. Number 3, 4 is harder and usually for people who do a lot of forms where it isn't convenient to stop and run to a pencil sharpener often. Number 5 and up is used by draftsmen where their hands or arms may sweep across a drawing while still in progress. Lead this hard won't come off a technical drawing and smear making it look more like a pastel pencil portrait. Which way that the clay content swings, I don't know so trial and error may apply. Good luck.