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Do crystal radio's work when 'digital radio' has taken over? Answered

For the past couple of days I have been interested and reading about crytsal radios. Having many issues recently, I do know that our radio stations here in Australia went to 'digital' and they removed analog T.V, but I never heard anything about radio. I can still pick up AM radio stations on the radio or in the car, but are these signals sent differently that a crystal cannot pick up?

I attempted 2 versions of a foxhole radio, no luck at all there. So I went to Jaycar and bought this: http://www.jaycar.com.au/productView.asp?ID=KV3540

This proper PCB, with a galena diode still does not work. It also doesnt use a ground. Unless my aerial needs to be bigger which I doubt! I am using a 30ft spreader aerial. Later today I will stand NEXT to a radio station building which is only 2km from here, if it does not work, then no crytal radio works over here anymore which would really suck! How could they remove it!?

And if I am wrong about the crystal stuff, then im still mad that the analogue technology has been removed anyway. It should sit there for anyone to explore.

18 Replies

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auraofasaint (author)2015-02-26

My 8 year old daughter made this one yesterday and grounded to radiator, worked well in uk, picked up 2 stations, one faded in and out, the other constant.

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simonyu (author)2013-04-12

Hey i got the same kit and it doesnt work .. i dont know why.
do u know if the wire the kit contains is supposed to be the antenna?

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AtomRat (author)simonyu2013-07-24

I created a 'standard' setup as most radio's use, I setup a big 24 foot long antenna outside, and also used a fresh ground. It still did not work, I don't know, I have gone back to crystal many times and never recieved a signal. Sorry for the delayed reply

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steveastrouk (author)2012-10-17

No, in a world with only "digital radio, crystal sets won't work.

However, AM isn't likely to die out anytime soon !

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rickharris (author)steveastrouk2012-10-17

Long after you and I have gone!

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rickharris (author)rickharris2012-10-17

Actually to take the question literally - yes they will always work but may not eventually have anything to receive.

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Re-design (author)2012-10-16

I'm not sure about Australia but the US went to digital tv but AM radio is still analog. Foxhole radios using the safety pin and pencil lead are tricky to get working. Sub an 1n34 diode for the safety pin and it should work easier. 2 km from a radio station if it is am and you should be able to pick up the signal very easy.

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AtomRat (author)Re-design2012-10-17

Sorry, typo above, it is the Geranium 1N34. It is the reason I had bought the kit, that way I could tell if I can pick up radio at home. It still does not work at all, this is a proper pcb kit. Look at link please. And I'm no beginner when it comes to pcb work either, so all of that is fine. I'm going to have to talk to the radio station

..'should be able to pick up the signal very easy'

This is what I figure, and it isnt exactly the hardest thing to make, I did it when I was a kid years ago. It is why I am thinking it has been removed.

At a slight glance, if all else fails, can't I make my own simple broadcasting channel of my own to still have fun with crystal sets? Im not exactly interested in the radio station, more the technology

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steveastrouk (author)AtomRat2012-10-17

You need a good ground on the antenna connection.

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AtomRat (author)steveastrouk2012-10-17

My ground for the foxhole one is a solid copper pole going 2m into the ground with wet peat soil around it. My ground is fine there.

The instructions that came with the kit AM crystal radio specifically mentions not to use a ground as well: "Caution, never connect to ground, equal potential and phase will cancel out the signal received."

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steveastrouk (author)AtomRat2012-10-17

I've only ever built them with grounded connections.

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blkhawk (author)Re-design2012-10-16

+1 A 1N34 Germanium diode might do the trick. And an old telephone receiver to listen the sound.

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iceng (author)2012-10-16

I always thaught the earphones on these sets needed to be high impedance ( high resistance ) for the best sound.

A

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AtomRat (author)iceng2012-10-17

The link I supplied in the details has a kit that contains the high impedance earpiece. I also managed to make one from a piezo off a greeting card and put a 47k resistor across the terminals, it works exactly the same, seriously, look for my next instructable about home made components when it comes

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rickharris (author)iceng2012-10-17

Yes ideally you need a crystal earpiece to avoid loading the cct too much.

IF the radio spectrum goes totally world wide digital then no they won't work - BUT that will be long after you and I have gone.

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