Bhavin's Homemade Foxhole Radio

This is a video that I made a while ago showing my homemade foxhole radio. The whole reason for this video was actually because I made this for a science fair project and it worked at home, but when I took it to school with all the buildings in the way, I didn't get any radio station. I just made this video to show people that it actually worked and how clear it came. And at the same time I just talked about the parts and wires.

I am amazed at how clear this homemade radio is.

In this video, I show my foxhole radio tuned into an AM radio station. In addition, I explain about the parts and wires of my radio and what role each of them play.

Category:

Science & Technology

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[mdesm2005]

I don't think that moving the needle will pickup a different station. All that does it make contact to crystal on the blade to act as a diode. To pickup different stations, you need to connect to different places on the coil. That will vary the inductance form the coil. It's the amount of inductance from the coil that determines to what frequency the system will resonate. The diode clips the negative portion of the signals to which the coil resonates.

[bhavinparmar90013]

@mdesm2005 You are correct. I made a mistake in the video. You can see me correcting the mistake on the annotation at 2:23. I actually modified this radio to make it tunable a few weeks after recording this video. But that was over 3 years ago. I don't remember the details, but I know that I had an 'arm' over the coil that could move left and right, which did vary the inductance as you said. (The cat whisker is just a way to fine tune the radio.) My apologies for this mistake.

[MediaHoax]

Did it take a long time to make the coil?

[bhavinparmar90013]

@MediaHoax It didn't take too long. It just takes patience, diligence, and an hour or two. You rather take your time and do it right the first time; don't try to rush it. I also had more 'turns' around the coil than some of the tutorials online stated. I can't exactly remember the amount of turns I had, but I think it was around 200-250.(Tutorials online say to do around 120) This increase in the amount of turns could have been the reason to why mine worked well.

[TheChinese01]

So if my house is not enough radio wave , where is the best place to test my radio?

[bhavinparmar90013]

@TheChinese01 Maybe try different places in your house and maybe try outside and put your antenna in different shapes. ie. put it vertically up like up the side of your house or something of that sort. Try a longer antennae or just troubleshoot. I can't really help you sorry.

[donovanfonseca]

One of the best foxhole radio videos i've seen on youtube ;)

[bummiesstudios2]

wow.. kids are smart these days :S

[ffgamerboy9]

so cool

[FSstudios1]

why such a long antenna? im a ham radio operator so i know what im talking about. but you could have a foot of wire and get good reception. also you need to be a little more specific when explaining your invention. good luck! and keed creative!

[brokenarrow2222]

when i was 8 years old in 1958, we had a science fair. one of my classmates made one with his father's help. He used batteries for his power and an ear piece from a transitter radio for his audio receiver. Bring memories back.

[bhavinparmar90013]

@TheChineseRegarding your previous comment, it could be your razor blade.Make sure you have "blued it" and maybe try another type of blade.Your antenna might be too short, your wires may not be connected properly, etc.Troubleshoot, because there are many possibilities for it failing to work.My radio didn't work at the very beginning, but then I re-wired everything and it was perfect.It could be that you have bad reception on your area, but double check that everything else is connected properly