aHR0cDovL2ZyZWVzaGlwLmNvLmtyThis voice recorder is an improved version of a single-transistor radio. A single-tube machine is a radio with only one amplifier (transistor or vacuum tube). It only relies on one amplifier to complete the complex processing process and restore the weak electrical signal to the human ear. audible sound. Because the circuit is extremely simple, usually this circuit is designed to work in a duplex mode, and a regenerative circuit is added to increase the performance of the circuit to the limit with few components.
The single-pipe machine is like embroidery on the tip of a needle, building a beautiful world in a mere square inch. The single-tube machine is a classic work in the history of electronic technology development and the crystallization of human wisdom. Today, the significance of the single-tube machine is no longer a means to solve the shortage of materials, it represents an ingenious design thinking.
Today, the price of electronic components is no longer intimidating, and the quality is much better than in the past, but the single tube machine still has a large number of fans who still talk about the working principle of the single tube machine and enjoy the single tube machine. The fun of the machine, and constantly trying to improve and enhance the performance of the single-tube machine.
The single-tube machine circuit is simple, but the principle is not simple. It uses a handful of components to complete various functions and achieve a certain performance, involving various fields of analog electronic technology. Therefore, the single-tube machine is not only a palm pet that is worth playing, but also a key to the palace of electronic technology.
This is an improved version of the single-transistor radio. On the basis of fully respecting the classics, some improvements have been made, so that it can maximize the potential of transistors with the least components and the most concise circuit to achieve the most satisfactory listening effect.
Take off her clothes, like a magnificent work of art:
¡¼Commodity name¡½KR-1T voice recorder's improved regenerative single transistor radio
¡¼Features¡½
1. The shell is printed with the words and pictures of the chairman's quotations, allowing you to cross time and space and travel to that fiery era;
2. It is easy to assemble, if there is no error in the installation, it will sound as soon as it is installed.
3. Use No. 7 dry batteries, which are economical, and rechargeable batteries are also available;
4. The headphone socket has a power switch, and the power is turned off when the headphone plug is unplugged.
Actual combat test: According to the test of our shop, the machine can receive some radio stations in Zhejiang and Shandong in addition to clearly listening to all the medium wave stations in this province (Anhui), and the effect is not bad. In our test, the general 32 ohm Walkman headphones are used in series, and the sound is not large. In a relatively quiet environment, the listening effect is still good, and the noise floor is very small. Using two 130 ohm telephone receivers in series, the effect is not as good as 32 ohm earphones. If you have a high-impedance earphone, you might as well try it. I think 32 ohms can already be used. It is cheap, affordable and easy to carry.
¡¼product description¡½
1. The circuit diagram of this kit has been slightly changed compared to the traditional circuit, which is an improved version of a single transistor radio;
2. The base of the circuit board is glass fiber material, the thickness is measured about 1.5~1.6mm, the green oil is white, the pad is sprayed with tin, and it can be directly welded without grinding.
3. There may be some scratches and dust on the board base surface and copper foil surface, as well as traces of board washing.
4. The magnetic rod antenna coil in the kit is a stock product, not a specially customized product. If it is used directly, the radio may be squeezed to one end of the variable capacitor stroke. Players can increase or decrease the number of turns of the primary coil, and the available signal can be generated. For debugging, please read the kit manual for details;
5. Regarding the connection method of the magnetic bar coil: the magnetic bar coil has a total of 4 wires, first find the one that is farthest from the other wires, which is one of the primary coils, and the label is 1, and then use a multimeter to measure the other three wires, of which One is connected to the No. 1 wire, this is the primary No. 2 wire identified in the circuit diagram, and the other two are the secondary No. 3 and No. 4 wires. If the installation is completed and there is a whistle, replace the No. 3 and No. 4 wires by welding. Just install it. The regeneration coil can be made of single-strand network cable, see the instruction manual for details.