How to make an AM radio receiver

In the early years of radio, the acquisition of receiving equipment was expensive, so many people made homemade devices called galena radios. Nowadays, with few materials and by changing the galena for another material with similar characteristics, we can make an AM radio receiver home-made in a very short time.

AM radio receiver

Materials needed

- One 18 cm long ferrite rod (Ferrite is a cement dye available in hardware stores).

- A 100 pF capacitor.

- One IN60 diode.

- A high impedance hearing aid.

- Two small crocodile connectors.

Antenna for radio.

- Grounding.

- Cardboard.

- Enamelled copper wire 1mm thick.

Construction of the receiver

To begin construction of the radio receiverIn this way, we make a cylinder of cardboard with a length of 17 cm and a diameter large enough for our ferrite rod to slide through.

Once the cylinder is made, we make the winding in the following way: we start at one end of the cylinder and with the copper wire we make about 8 turns and leave a bit of wire protruding (for tuning), we cut the wire and we make a new winding of 8 turns right next to it. We repeat this procedure until we get about 80 turns or 10 different windings.

AM radio antenna

When the winding is finished, we can place the tube on supports to prevent the assembly from disassembling. Once the winding is fixed, we take a connection at both ends of the winding and connect the capacitor.

Now, we mount the diode in such a way that it is sufficiently fixed to prevent it from disassembling. Also, we make the ground connection, which can be done in a nearby pipe or a previously grounded socket. The electrical assembly can be seen in the following figure.

AM radio scheme

Next, we locate the antenna of the receiver Just above the coil, care should be taken to position the antenna as high as possible. The antenna should be approximately 15 cm long, remember that the longer the antenna, the better the reception.

Once the radio has been assembled, all that remains is to tune the stations. To do this, we place the crocodile connectors in two of the nine connections that we created in the coil and carefully move the ferrite bar that is inside the cardboard. Remember that the porosity of the ferrite rod is vital for the tuning of the stations, which we can hear thanks to the magnetic field created by the winding.

AM radio antenna

4 thoughts on “Cómo hacer un receptor de radio AM”

  1. sergio gabriel

    this is a very basic galena radio, basic but effective, only that finding 2000 homs headphones is very complicated, it can be solved by connecting instead of the headphones a 220 to 12v trafo in inverted form, or cea where the 220 v would enter would be the output of the headphones and this adjusts the impedance which allows listening with a common headphones, of cellular for example.

    "sharing information strengthens ties and enriches each other".

  2. Very good and seems very simple to make, only a few components are needed.

    Excellent idea 🙂

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