You will need
- Wire with enamel and silk insulation diameter 0.3-0.6 mm
- Round ferrite rod from an old radio
- Exercise book
- Glue BF or nitrocellulose
- Capacitor 1500-4000 pF
- Jacks for antenna, ground, phones
- Phones high-impedance or low-resistance and step-down transformer (for example, the output from an old radio, TVK from an old TV or a transformer from a PA speaker)
- The semiconductor diode the germanium point (for example, D9, D2, D18, ГД507, Д310)
- The antenna wire is bare copper with a diameter of 3-5 mm (the antenna cord) 15-20 m
- Wire copper stranded insulated
- Plate of insulating material — Micarta, textolite, Plexiglas
- Soldering iron
The ferrite rod to wind the strip of paper with a width of 7-8 cm. Paper wrap in several layers, securing them with glue BF to get a tight paper cylinder. The cylinder should be easy to navigate through the ferrite rod after drying.
Received a cylinder wrap 100 turns of wire with enamel and silk insulation. Wrap the wire turn to turn. The ends of the coil and secure with glue. Turned out the coil that the scheme is designated L1.
Assemble the receiver according to the specified schema. The polarity of the switching diode in this case is irrelevant. The output of the receiver connect high-impedance headphones (phones) If those are not there, you can use low-resistivity, for example, from the player. But they can only be connected through step-down transformer. In this case, the high impedance winding of the transformer is connected to the output of the receiver, the headphones to low impedance winding.
The crystal radio can't work without a good antenna and ground. Make grounding. Using flexible stranded wire connect the output to the "ground" receiver, stripped of paint and rust steel radiators. Even better to connect this outlet with buried in the ground to a depth of 1-1,5 m with a metal object. It is desirable that in this location and at this depth the ground was wet.
The antenna should be placed as high as possible. For example, on the roof of the house. You can help & how shipping to get it on the high tree. In an extreme case, position it around the perimeter of the room in your residential home. However, in a reinforced concrete building such an antenna will not work. The antenna is a bare copper wire length of 15-20 m.
Tune in to the radio station by moving the ferrite rod inside the coil form. If you find that no radio station is not in the range settings, or faint on the edge of the range, make another coil, with large elementsin number of turns. Usually the coil can be from 60 to 220 turns.
If the receiver antenna, to ensure Gazobezopasnost it is necessary to close with any simple switch of the antenna wire and ground, when not in use by the receiver or during a thunderstorm. The approaching storm can be seen by appearing in the headphones cod electric razrezov.
As a metal object to ground will suit an old bucket, a piece of batteries, water pipes, etc.
Advice 2: How to make a radio
The simplest kind of radio detector. In 50-e years of the last century, the Soviet industry was producing one model of the detector receiver – "Komsomolets". In more recent times, the Assembly of such a receiver was considered a good workshop for beginners in ham radio. We offer recommendations on how to make a radio receiver with his hands.
You will need
- Coil from under the thread, winding wire marks PEL, electromagnetic headphones, point the diode (detector) type D9 or D2, a few capacitors, clips or clasp plug receptacles
The simplest crystal radio set you can mount on plaque or panel. But this is not necessary in order to create a workable machine. An experienced model can be collected directly on the table where the expanded view will lie its details. This visual model allows you to make the receiver the necessary changes to correct the mistakes and make adjustments.
Take an ordinary coil from under the thread, it would be the base. Wrap the coil nawalka approximately 450 turns of wire. In this case every 80 turns to make the bends. In places of bends, twist the wire in the form of loops. You got a layered coil with multiple taps.
Now you need to strip the ends of the insights and taps mounted on the coil. Do this carefully to keep the wire. Now you can proceed directly to the Assembly of the detector receiver.
Connect the beginning of coil with one of the outputs of the diode detector, and it will end with one of the contact legs of the wire headphones. Unoccupied detector and phones connect appropriate size wire cut.
To the conductor extending from the beginning of the coil to the diode securely fasten the wire, which is assigned the role of antenna. The end of this antenna wire should be pre-cleaned from the insulation.
Now you need to attach the cable grounding wire to the conductor connecting the end of coil with head phones (call it the grounded conductor). During the experiments with the receiver we switch the grounded conductor from one output coil on the other conclusion.
Put on the head phones and listen. It may well be that you will hear nothing. This is possible for the reason that the detector receiver is not tuned to a radio station, kisimul in the vicinity of your location. In this case, try to adjust the receiver by changing the number of turns of the antenna circuit of the coil included in the circuit of the antenna. A simple crystal radio can be set to radio or medium wave bands. However, due to objective design constraints, the receiver can receive signals not every transmitting station, in particular, is very remote.
Since you created the detector by the receiver can carry out interesting experiments that help to understand how it works and to gain valuable practical skills of designing of radio equipment.
Advice 3: How easy it is to make the output on the one hand
This element is quite simple in execution, but at the same time is very important, as is the basis for other, more complex elements. No matter what you build, you will be able to make out on one hand.
Pull-UPS and push-UPS. So you easily carry this item, learn how to catch up on the bar 10 times, not tucking in his legs and keeping them straight, and exercise from the floor at least 20 times.
Checkbox. The next step is to fix the check box, as shown in the picture. To make it easier to make this part of the element after pull-UPS you can put the forearm parallel to the crossbar, and then out into the box.
To do push-UPS on a horizontal bar. After you leave the check box to fix the second arm on the horizontal bar, as shown in the picture. To make it easier to do it, you can have a little wobble. With this position you need to do push-UPS on a horizontal bar and out on the straight arm.
Be careful when picking a box, since if it is off hand, you can hurt your thumb.
Once you may fail, but the important thing is perseverance and regularity. If you develop these two factors, achieve great results.