Introduction: Projects From an Old Casette Player

Picture of Projects From an Old Casette Player

Hi! Did you ever thought that you can build many gagdets from an old electronic device? Yes, maybe. Now I'll show you that what can build from an old casette player/radio. I made an FM transmitter bug and a wind turbine battery charger. The most of the parts are from the casette player. I only needed a 9v battery, a propeller and a AA battery holder. The wind turbine is the easiest project that I've ever made I think because the circuit only requires the 6v DC motor from the casette player and a diode from the circuit.

The FM transmitter is a little bit harder project but works fine. Now let's begin!

Step 1: Parts and Tools

Picture of Parts and Tools

For these projects you'll need only the casette player, soldering iron and some crafting tools.

Step 2: Salvaging Components

Picture of Salvaging Components

Open your casette player or radio then take out as much electronic components that you can. I've found inside a bad speaker :-( , but the other components were good. Removed capacitors and and te resistors. Then I found inside a microphone. These parts are perfect to make an FM transmitter from them. And the 6v DC motor is also perfect for a wind turbine.

Step 3: FM Transmitter

Picture of FM Transmitter

So you'll need :

  • -a BC547 transitor
  • -1nF and 22nF capacitor
  • -4.7pF and 20pF capacitor
  • -a coil with 4 turns-a small piece of PCB
  • -9v battery clip
  • -wire for the antenna
  • -4.7k and 330ohm resistors

Step 4: Heat Up Your Soldering Iron

Picture of Heat Up Your Soldering Iron

Following the circuit diagramm make the circuit on a small piece of PCB. Add the 9v clip and the antenna then you're done.Add the 9v battery and test it with your phone's FM radio or with an FM reciever. If don't works try to modify the antenna's position until you'll get the chanell.

Step 5: Test It!

Picture of Test It!

But what is a FM transmitter?

Is a device that can amplify the microphone signals and transmitts frequency modulated signals via radio waves to your phone or to a reciewer. Works between 90 and 106mHz. My one was 97.8.

Step 6: The Wind Turbine

Picture of The Wind Turbine

You'll need the DC motor, a water bottle a germanium diode from the circuit of the casette player, a propeller and a AA nattery holder. That's all! The simplest wind turbine on the world.

Step 7: Soldering

Picture of Soldering

Solder the motor and battery together but add the diode between the positive wires. The anode needs to be connected to the motor's positive output and the catode to the battery's positive wire. This is very easy.

Step 8: Crafting

Picture of Crafting

Glue the turbine to the cap of the bottle and the battery holder to the bottle.

Step 9: The End

Picture of The End

Boom! We've made two nice projects only with reusing components from a casette player. Have a nice day, and thanks for wathing!


bostroglav (author)2015-07-20

nice instructable.
I searched in two old radios, but I did not find a bc547 transistor... could it be replaced with an other transistor?
If yes, tell me :)

agis68 (author)bostroglav2016-12-11

but this series of transistor is very popular and cheap...

bostroglav (author)agis682016-12-12

i found them... thanks.

Imetomi (author)bostroglav2015-07-20

yes, no problem

krstecd12 (author)2015-05-17

Great project, but can you tell me where can i find fm radio receiver circuit i want to make it.

Sorry i have bad english.

Imetomi (author)krstecd122015-05-17

You can use a simple FM Radio or your phone for the reciever, but down, in the comments, you can see a reciever and transmitter circuit. Thanks!

Isfaaq (author)2015-05-02

How can I regulate the frequency? Thanks.

jerenmie (author)Isfaaq2015-05-16

use variable capacitor

Imetomi (author)Isfaaq2015-05-02

The frequency can be regulated with the trimmer capacitor if you have. In my casette player I didn't found.

zach krueger 7 made it! (author)2015-04-26

this was a cool quick project. I attached the windmill to my bike (which around here is always windy), on top of moving quickly on a bike... charges rechargeable batteries ultra fast. surprisingly very fast!

Imetomi (author)zach krueger 72015-05-02

Looks good! Really good! Did you checked the output voltage?

Isfaaq (author)zach krueger 72015-05-01

Be wary though! Too much current may cause serious damage. Use a resistor to limit the flow of current.

Isfaaq (author)2015-05-01

step 2/9, there's a small typographic error. Very nic project. Simple and Sweet ;)

Nikolajco (author)2015-04-27

how can i connect my phone on the transmitter ?

Imetomi (author)Nikolajco2015-04-27

Open the FM Radio app then search ths frequency of your traansmitter.

Cyberchipz (author)2015-04-19

Why doesn't the battery make the motor run; not enough juice?

Imetomi (author)Cyberchipz2015-04-19

The diode blocks the current flows backward.

Cyberchipz (author)Imetomi2015-04-24

Oops, should have caught that... my eyes are old, I looked again... There it is, it's so tiny I overlooked it. lol. Thanks for the reply.

BruceE3 (author)2015-04-22


pankajp (author)2015-04-20

Please tell me what is range of this transmitter

And tell me how can i increase the range

Imetomi (author)pankajp2015-04-20

Hi! The range depends on the input voltage and on the length of ths antenna. With my 15 cm antenna and with a 9v battery would be 40 meters.

pankajp (author)Imetomi2015-04-22

Thank you for help!!!

łsokołowski (author)2015-04-17

why you don't use VC1 on your PCB?

Imetomi (author)łsokołowski2015-04-17

The role of the VC1 is that you van tune the frequency. I choosed a ceramic cap between 10 and 40 pF anx works on a sinlge frequency.

łsokołowski (author)Imetomi2015-04-19

okey. i want to do this transmitter but don't know when i have a time ;-)

im ok (author)2015-04-17

What kind of PCB is it? Where can i buy it?

Imetomi (author)im ok2015-04-17

Sorry I don't know but you can buy from the Radioshack if you live in the US.

GregQ (author)2015-04-17

Doesn't that wind generator need voltage regulation? I'm sure the output is going to be all over the map from 0V to maybe 12. Also, NiMH & Lion batts need special charging parameters so it looks like Nicads for this. Why not put a regulator chip on it, maybe hacked from another power supply?

Imetomi (author)GregQ2015-04-17

I wrote in prevoius replies that I did't checked more than 5 volts on the output. And there's the 10% rule that means that if I charge the battery with a current that is smaller than the 10% of the capacity the battery don't be overcharged. Example I can charge safely a 2500 mAh battery with 200mA. Well I know that after a long time the battery may dead but this will need at least a week.

omikeo (author)2015-04-16

nice job, i ride my bike a lot with my radio/mp3 player, it would be nice to have a mini turbine to recharge that battery as well as the light batteries, or i may be better hooking up the generator to the tire ? thanks, mike

Imetomi (author)omikeo2015-04-16

Thanks, the generator will make the bike slower. That's the only problem. I have another instructable where I present a 5v wind turbine made from a CPU fan. That would be the best solution for you.

fred3655 (author)2015-04-16

Does the wind turbine put out useful power? Like to charge a cell phone?

Imetomi (author)fred36552015-04-16

Well the voltage is about 3 volts but the current is enough to power up a 5v step up circuit, so would be possible.

Imetomi (author)fred36552015-04-16

Sorry but no, but can charge 2 AA batteries in the same time.

toby7 (author)2015-04-16

What gauge wire and spacing of coil?

Imetomi (author)toby72015-04-16

The coil spacing is 1.2cm, and the wire's gauge is about 24# I think. Is salvaged from the casette player.

charles543 (author)2015-04-16

Where do we get the fan blade? It looks like it's from a computer fan.

Imetomi (author)charles5432015-04-16

Yes, it's from a computer, but works also with others.

pushchit (author)2015-04-16

Can we make it a two way communicator like a walkie talkie. How?

Also, what is the range of this communicator

Imetomi (author)pushchit2015-04-16

Great idea! Yes you can if you build two devices with a circuit like on the image below. The range depends on the lenght of the antenna and on the input voltage. With a 9v battery is maximum 100 meters.

discostu956 (author)2015-04-15

this is great! Thanks for putting this up. Nice project to do with my son I think (drag him away from mine craft)

Imetomi (author)discostu9562015-04-15

:D :D :D Minecraft is a good game but electronics is a way better I think. Thanks for the funny comment!

discostu956 (author)Imetomi2015-04-16

Cheers. it's all he does!

had a question, or a few actually. The diagram shows variable capacitor, but I notice you didn't use one. Not necessary then?

Also, I gather it's frequency is related to the capacitor on output (I would think the variable cap is used for tuning) and also on antennae length. Is that correct?

Imetomi (author)discostu9562015-04-16

Hi, yes, I did't found a variable capacitor but the capacitor's value it was 10-40pF so I used a 20pF. It's much more better with a variable cap, but in the case of emergency I used a simple capcatitor.

The lenght of the antenna needs to be between 20 and 10 cm or longer.

Imetomi (author)Imetomi2015-04-16

I recommend this site for your son, if he likes electronics.

discostu956 (author)Imetomi2015-04-16

Thanks guys, much appreciated. off the garage to find the parts now. If he enjoys this I'll show him that site and see if I can spark his interest more. Cheers

BeachsideHank (author)2015-04-15

Great reuse of a defunct machine, nice work!

EvolvedAwesome (author)2015-04-15

These are some really cool uses for Cassette Player Parts. Awesome job!

About This Instructable




Bio: Hi, I'm Tamas (Thomas), a 17 years old Hungarian guy. My hobby started more than 10 years ago. I learn electronics, physics, programming, IoT ... More »
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