How to Make a Foxhole Radio

During World War II, GIs in the field built really amazing simple radios to listen too. These were made with materials that they could get their hands on and were small enough to carry around in a big pocket. You can modify this design if you want to set it up so that it's tuneable too! To see all the plans, go to makezine dot com slash podcast!
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[@Themaxleydog]

jesus i watched this video in 2007 once..... remembered it.... and found it again 14 years later

[@sallycarroll6329]

What does JESUS have to do with this?

[@greg2818]

@@sallycarroll6329a lot of

[@transcendbeing]

​@@sallycarroll6329wow you're truly a very intelligent individual

[@duaneritter3932]

@@sallycarroll6329 Alright Sally, time for arts and crafts...

[@yoramstein]

Heating the razor blade creates a dioxide layer on the blade (2 materials) which turns the razor to a detector (diode). I think kind of that layer is also being used at the gate of mosfet transistors.

[@berkozkaya8365]

We did it with my friend when I was 12 years old. Although we cannot get sound from the radio, I am an Electronic engineer candidate right now :)

[@AliasUndercover]

I bet you could get one to work now.

[@25_26]

i made one when i was 8. It is not a big deal.

[@berkozkaya8365]

@@25_26 congrats mate im happy for you

[@dudewithout_a_face5573]

How did it go? Your uni I mean

[@ethancobb4002]

Just a candidate? Not even an engineer?

[@GGWalace]

12 years and the quality of the video is amazing

[@DarkenedCrux]

This was the very first KZbin video I ever watched, oh the memory's

[@texaselite1355]

Hahahahaha

[@UpcomingJedi]

I watched Me at the zoo. Gives me the willys to know what you watched. Its so interesting. Im going to like this comment and have my followers all like it too so you get money from KZbin.

[@arthurmead5341]

@@UpcomingJedi what lol

[@bubbythebear6891]

I actually had to check the upload date. The production value is so high!

[@AninoffsMagister]

Did you watch it while you had the movie “Hart’s War” on pause…. Like I do now? 😂😂

[@AdamEbelgccengineering]

This video is over 9 years old, becoming a great classic crystal set project video.

[@dixiegracebrown]

13 now 😂

[@agostinodublino1387]

@@dixiegracebrown SIXTEEN NOW 💯🔥

[@johnblackmore2067]

@@agostinodublino138722 now! 😅😳

[@lunhil12]

Learned to make them in the scouts back in the 70's.

[@pierre5325]

Great Brie, Another project to do with my great grandson. Thanks so much. pierre from New Mexico I like how clear and easy to understand your vid was with a bit of history thrown in.

[@merrittorius]

They did this in Masters of the Air! Awesome video.

[@Reubenhubert]

This is exactly the kind of plan I was looking for. Years ago I found plans in a real old boy scout manual that used the cardboard tube and cats whisker, but it used a galena crystal. I think it also used varnish coated wire and the varnish was removed from an arc that the tuning arm traveled.

[@StuPadazzo]

Props for showing the entire learning curve, failures and all. It helps us understand the diagnosis process better. Thanks.

[@kyCap222]

I love the emergency siren in the back ground wile your heating the rasor

[@OurInfiniteFuture]

The problem you had with the Razor blade was the rust resistant coating that comes on modern metal to make it last longer. you can burn it off or scratch off the coating with sand paper

[@GeneSavage]

That sound quality's pretty impressive! It's a shame you weren't able to get a music station. People don't know AM can sound GREAT because radio manufacturers use really cheap components and roll off the lows & highs. Great job!

[@JohnBerthoty]

I made one just like this over 50 years ago. Fun to see it resurrected! The reason the 'blued' blades work better is because they have a selenium coating. You can put the point of the safety pin directly on the blade with those... no pencil required. Thanks for this vid!

[@shahzad612]

Great Job. Your dad, McGyver,would be proud. I really like the fact that you actually go through some mistakes and show people it's not a one shot deal. Thanks for sharing. Great Post.

[@sheriefelghandour2760]

Just wonderful

[@CubejamF1]

All you need are these.... Later in the video.. and these and these and these and these and these and these.

[@rogerdodger8415]

Cubejam And in your case... You'll need a brain.

[@texaselite1355]

Cubejam LMFAO

[@Parlay007]

I made one of these once when I was in grade school. I bought a kit and put it all together. I was super proud of myself!

[@fastmoni]

Hey, we love your video! My son and I enjoyed it very much and the best part, it worked! Keep up the fun stuff. Many thanks!

[@ksarnaszek4436]

Like a MacGyver! AWESOME!!!

[@nbarrager]

2:33 they found you, bree...

[@CassetteMaster]

AWESOME! It works good! It's neat how the heated blade makes it work as a diode.

[@thinkingjohn2099]

I built that today and it worked ! Thanks for posting

[@kyleburns3925]

Haha sound like mike francesa when he played the radio station!

[@harmlesshawk1794]

XD trying calling in and say "I'M USING A RADIO DONE BY GI'S IN WWII!" "Who is this guy?" "I CAN'T HEAR YOU,THIS RADIO IS SOFT!" "...-,-"

[@GratefulCraig]

Real cool! I watched it twice and that looks like a real cool weekend project.

[@canuma100]

I made this 14 years ago when i was a child. It really works. I used slightly different things but the principle is the same. Its fun and sometimes usefull in certain situations

[@natemcgraw3690]

better product than the makerbots

[@ufoengines]

Heard the toilet paper companies are getting rid of the tubes. Then what?

[@3dgamerman]

buy a radio

[@28YorkshireRose12]

Easy, measure up an existing tube while you can, and make a replica tube out of printer/copier paper. Or, there is nothing to say you can't use plastic waste pipe, or even a small medicine or drink bottle. The tube doesn't even have to be of any specific material. You could even get more adventurous and dispense with the paper tube altogether and build a simple frame antenna, but I digress.

[@johnnywad7728]

You MUST have a CRYSTAL earpiece/ headphones! This is crucial to the functioning of the foxhole radio!!!!

[@Zecastronomo]

I and my father did it when I was young, in the sixties. Very nice to see it again.

[@archangel20031]

Page not listed or has been moved?!?!?! Learn nothing there!

[@nb4032]

late,but:cdn.makezine.com/make/wp_foxholeradio.pdf

[@kevoice]

Warning: This may turn out to be a Fox Talk Radio :)

[@Xposse]

That's still a FOX Hole radio... Not to be confused with an Ass Hole radio...

[@IamFatnickc]

Great story & project! Thank you Bre!

[@willyb7353]

Sounds suprisingly good.

[@user-dt6ws7yv5o]

Thank you really, I finally understand the simple radio structure.

[@DrLlamagon]

That's so great! what a great thing to use your time on!

[@rjy8960]

This is really, really nicely done. I've not seen a razor blade used as a detector before. Thanks!

[@drew6017]

Great video. One of the best I've seen about the foxhole radio.

[@MikeGervasi]

I tried to make one of these a while back with a kit and couldn't get it to work. Really tough for some reason. Bre I'm glad that you actually showed some "failures" along the way on this one. Keeping it real and showing that electronics aren't always a perfect science :)

[@dogboymalone11]

HERE HERE, WELL SAID.

[@purplemutantas]

Nice! Glad to see you had a fire extinguisher on hand.

[@joycepalm9190]

My brother did this when I was a little kid ,and it worked! 5-yr old learned electronics! Gotta love big brothers (even when they hit you for touching their stuff).

[@irishdevil]

bluing is a process of heating and cooling that not only strengthens the metal but also does something to the internal electron configuration.

[@ADDICTEDTORADIOS]

I'm a radio collector, thanks! I'll try this. Cool stuff.

[@AshsArtwork]

Nice! I made one of those for my History of Broadcasting class back in college.

[@trevormckay677]

Him lighting the torch with sirens in the background is absolute comedy gold

[@2passnthru2]

it is the rust spots that make the good connections.. different size rust spots get different stations. you can get blue blades from crystal radio parts supply.

[@bruhmania7359]

This is so high quality for 2007 damn

[@kcmazdaguy]

@yasowhatup it is the air capacitance of the air coil. it is very low, however, the inductance of the open air coil is also very very low. thanks for you question

[@RolandArnedo]

what a nice project, i will try this sometime.

[@fletcher0102]

you are the man! a "macgyver" radio...that it!i finally found my jota-joti project topic! thanks!

[@brianemory1593]

great video, reminds me of my younger days and just getting started. you also wear you shirt the way i did then...and well now.

[@kcmazdaguy]

@lukasm14 this device shown is an AM radio. 102.6 MHZ is in the comercial FM band, where transmissions are in a different format. That Format is Frequency Modulation. Amplitude Modulation is "detected" by the diode action of the "cat's whisker" or, razor blade/pencil tip combination. Frequency Modulation, is deteted by a more complex method, and requires more complex equipment.

[@nathanallan1]

Very cool project!

[@nicholasgonzalez]

nice yesterday i started making this, my dad had some old world war 2 german razor blades so i took one. I made my coil with 300 turns, and used my washing line as an antenna and it works GREAT!

[@855h0le]

Yes u were correct about the type of Metal Treatment. I think its called "negative resistance". The coil is the antenna. The razor blade is the oscillator.

[@bodunchar]

lol great have to come back to these vids another time!

[@bleddyuffles]

That's actually really awesome! :D

[@field16]

The pencil lead / razor blade combo is a basic diode, allowing the current to flow in only one direction.

[@Team-fabulous]

Very well done. Super video....

[@malgray2]

Yes the number of coils will affect the tuning frequency. Using a ground maximizes the potential difference between the radio wave and ground. In other words it makes the signal bigger.

[@andersonsds]

Maneiro, já conhecia mas não lembrava! Parabéns!

[@outslider1]

Cool project, have to do this!

[@DaveTadlock]

Cool project. Easy to make tunable. Just move the paper clip on the right to the center of the coil and stretch out the paper clip so that it rests on the coil with spring like tension. Make the coil almost twice as long. Use the edge of a metal file and remove about an 1/8" strip of enamel coating from the magnet wire. Tune by moving the paper clip across the coil to tap the coil in different places. :)

[@IsaacC20]

That's AWESOME!

[@timberwolves100]

@fifthStitch The ground wire is for preventing you from getting shocked from static electricity. You COULD run it without one but it you could get electrocuted or at the very least zapped when the electric components built up enough electricity. You could just attach the ground wire to anything metal that will absorb the electricity.

[@AnimationShorts1]

Holy crap this is so cool!

[@team222badbrad]

That is soooooo kool! I built a superheterodyne radio in high school and that took days in class to solder up. I didn't know that this was possible though! Oh well back to my 3d printing duties

[@cornej92]

Great video. Thanks for making it.

[@doccpu7]

The razor blades had to be rusty or corroded so the contact point ( a bent wire or safety pin) becomes a diode. A very good diode was a green penny or other corroded coin. I finally did it with a galena crystal which is like the tiny crystal in a 1n34 diode. Which works very well.

[@StephenCooteNZ]

Cool !! I had heard of 'cats whisker' detectors but up until seeing this I had no idea what they were. Thank You.

[@Mindraker1]

Totally awesome and simple. Beginner hams would totally dig this. Perhaps a safer substitute for the burned razorblade, but otherwise, I totally dig it.

[@lhmcfield]

You can use pipe for tap water, you can use a gas pipe, you can dig a whole in your garden and dig in a big metal plate to which you connect the ground lead wire.

[@CuriousEarthlings]

Dude that rocks!!

[@freesk8]

OK, that was totally cool!

[@gabrieldeoliveira8304]

This is extremely well made for 2007.

[@onijujitsu]

Good information! You could probably set up simple hand crank device to wind the wire around the tube, using the free hand as a guide - similar to a device used by smiths to coil steel wire for chainmail.

[@TomMcRand]

i like how, as you were getting ready to fire up the torch to heat up the razor blade, the sirens got closer.

[@clyde5057]

the razor blade and the cat-whisker or in this case the pencil "rectifies" the signal that is received. You can use an old Diode that just about anything electronic has a number of. The part usually has a symbol on like this →⊢

[@wilwad]

I live in Africa so I didn't really expect to hear anything as there were few radio stations: what I heard was electric sparks in the earphones though. Thanks to you, I will redo the experiment.

[@TAC19jm]

It was a wonderful lecture!!!

[@dutchman55]

10 years later, we may be needing to make these ourselves

[@candr]

@gomenaros One; safety, built up static electricy, two, its part of the antenna that uses ground radio frequencies (RF) to improve your signal.

[@w1wcn]

Nicely done! By the way, the talk radio is Mike Francesa of WFAN in NYC. One of the smartest sports reporters ever. He's syndicated, so not sure what station it was.

[@0rip0]

I did too, in the 4th or 5th grade, except I used a diode as a detector. I was always trying to improve the thing. Ironically, I lived on the east coast then but I live near Mesa now.

[@vidfuse]

cool video,my uncle who passed away a few years ago like making this kind of stuff

[@lfalecorel]

i remember over 10 years ago when I watched this, there was a lot i didn't understand from this video

[@gootch420]

now this is badass

[@nicholasgonzalez]

btw also if you use an audio jack and connect to + and - terminals you can use your computer speakers. Which is way more convenient as you can adjust the volume and you dont have to use the earphone

[@mikaeloification]

nice video...nice project ...tnks

[@1ukjunglednbraver]

@youngdrjung i think it works to amplify the signal might be wrong a longer antennae will do that for sure

[@QuantumMechanic_88]

Fascinating and thanks .

[@MrRoyalbonbon]

you just make my day. thanks

[@estefano551]

i didi this when i was 10 years old with this video. WAS AWESOME :DDDD THANKS

[@8bitvillain]

Great video!!!!

[@Ashish-zx4uc]

its a great thing i saw thanks BRE

[@be1nformed]

Very nice!

[@Aymiikeeganmelb]

Cool rainy day project to give a kid ...

[@UpcomingJedi]

No! They would eiher cut them selves or get shocked. Really, what kid would want this when they get cell phones and internet?

[@dinamirm.9290]

KZbin algorithm, you fool! I found this video not in my recommendation, but in the results i searched.