The avometer is the first measuring instrument. Encyclopedia of radio electronics and electrical engineering

Encyclopedia of radio electronics and electrical engineering / Beginner radio amateur

 Comments on the article

[an error occurred while processing this directive]

Amateur design is unthinkable without measuring instruments that will help check the details, measure the voltage in various circuits of the assembled structure, and monitor the signal passing through its cascades.

The very first device that is recommended to acquire is an avometer, which, in fact, includes three different meters: an ammeter, a voltmeter, an ohmmeter (the word AVOMETER is formed from the first letters of these meters). Such a device can be purchased at radio shops, as well as at radio markets operating in many cities. True, for the most part the device contains a digital indicator, which is why the cost of the device sometimes reaches several hundred thousand rubles. But on the other hand, the counting of parameters in it is "automated", and the result appears on the indicator in numerical form.

Nevertheless, we do not recommend rushing to purchase a digital device, an avometer with a dial indicator will cost much less, in which the readings are read by the angle of the arrow on the scale and the position of the range switch or probes in the input sockets. For example, on the Mitinsky radio market in Moscow, until recently it was possible to buy a foreign avometer (such devices are now called a multitester or multimeter) YX-2000A (Fig. 1) for 20 thousand rubles, and a more versatile YX-360TRn (Fig. 2) - for 50 thousand rubles.

Perhaps, at your home or in a radio club, there will be a domestic avometer that was popular at one time, for example, Ts20-05 (Fig. 3) - use it. For this device, in the next issues of the journal, attachments will be described that expand its capabilities. Although prefixes are also suitable for other avometers, including those foreign ones. For example, YX-2000A is small-sized, the type of measurement and ranges in it are set with one switch for 16 positions. With it, you can measure direct current up to 250 mA, direct and alternating voltage up to 1000 V, resistance up to 200 kOhm. In addition, the device is able to determine the suitability for operation of galvanic cells, batteries and batteries with a voltage of 1,5 and 9 V.

YX-360TRn also has one switch, but with 20 positions. It is designed to measure direct current up to 250 mA, direct and alternating voltage up to 1000 V, resistance up to 20 MΩ, testing diodes and transistors (with measuring the base current transfer coefficient - one of the main parameters of a transistor that characterizes its amplifying capabilities).

The domestic autometer Ts20-05 is capable of measuring direct and alternating current up to 1000 mA, direct and alternating voltage up to 1000 V, resistance up to 1 MΩ.

It is possible that you will have to choose an avometer from several models. What do you need to pay attention to? First of all - on the relative input resistance, expressed by the ratio of the input resistance to the set limit of the measured voltage (kbm / V). The larger it is, the more accurate the measurement results.

So, for the first of the above devices, this parameter is 2 kOhm / V. the second one has 20 kOhm/V for direct voltage and 9 kOhm/V for alternating voltage, the third one has 20 kOhm/V for both direct and alternating voltage. When measuring DC voltage on a range, say. 10 V input resistance of the first device will be 20 kOhm. second and third -200 kOhm. In the case of checking the voltage in circuits with low (kilo-ohm) resistance, the measurement results will be almost the same when using any device. If the resistance of the controlled circuit is high (hundreds of kilo-ohms), the first device will have a significant shunting effect on the circuit and the measurement result will be underestimated compared to the readings of the other devices.

In amateur radio practice, there will be circuits with very high (megaohms) resistance, for example, circuits of structures on field-effect transistors. None of the devices will be able to control the voltage in them. In this embodiment, the avometer will have to be equipped with a transistor attachment, which significantly increases its input resistance. We will talk about such a prefix another time.

An equally important characteristic of an avometer can be considered the number of measurement limits - the more there are, the easier it is to choose the most suitable one, on which it will be possible to obtain a high reading accuracy of the measured parameter.

Although an "Operating Manual" is attached to each device, it is not always possible to immediately understand the basic principles of working with the device from it. They are, however, few.

Before connecting the probes to the circuit under test with voltage, set the desired type of measurement and the expected limit on the autometer. It is advisable to start with a higher voltage limit, and then, if the indicator needle deviates slightly, switch to a smaller one. Please note that the most accurate result can be obtained by deviating the arrow to the second half of the scale.

When measuring the current in a circuit, you must first connect the probes of the device to it, and then apply the supply voltage to the structure (or cascade). The measurement also starts with a larger limit.

They act somewhat differently when measuring resistance, for example, a resistor with an erased rating on the case. The probes of the avometer are closed at the set limit, the indicator needle is set to zero (end of scale) using a variable resistor on the instrument case, and then the probes are connected to the resistor terminals.

At the end of work, do not forget to turn off the avometer (Ts20-05), set the switch to the off position (YX-360TRn) or to the position of the highest voltage measurement limit. Then the probes can be left inserted into the sockets (but not into the sockets for measuring resistance!), And during long breaks in work, they can be removed and put into the case together with the device.

Author: B.S. Ivanov

See other articles Section Beginner radio amateur.

Read and write useful comments on this article.

<< Back

Latest news of science and technology, new electronics:

Traffic noise delays the growth of chicks 06.05.2024

The sounds that surround us in modern cities are becoming increasingly piercing. However, few people think about how this noise affects the animal world, especially such delicate creatures as chicks that have not yet hatched from their eggs. Recent research is shedding light on this issue, indicating serious consequences for their development and survival. Scientists have found that exposure of zebra diamondback chicks to traffic noise can cause serious disruption to their development. Experiments have shown that noise pollution can significantly delay their hatching, and those chicks that do emerge face a number of health-promoting problems. The researchers also found that the negative effects of noise pollution extend into the adult birds. Reduced chances of reproduction and decreased fertility indicate the long-term effects that traffic noise has on wildlife. The study results highlight the need ... >>

Wireless speaker Samsung Music Frame HW-LS60D 06.05.2024

In the world of modern audio technology, manufacturers strive not only for impeccable sound quality, but also for combining functionality with aesthetics. One of the latest innovative steps in this direction is the new Samsung Music Frame HW-LS60D wireless speaker system, presented at the 2024 World of Samsung event. The Samsung HW-LS60D is more than just a speaker system, it's the art of frame-style sound. The combination of a 6-speaker system with Dolby Atmos support and a stylish photo frame design makes this product the perfect addition to any interior. The new Samsung Music Frame features advanced technologies including Adaptive Audio that delivers clear dialogue at any volume level, and automatic room optimization for rich audio reproduction. With support for Spotify, Tidal Hi-Fi and Bluetooth 5.2 connections, as well as smart assistant integration, this speaker is ready to satisfy your ... >>

A New Way to Control and Manipulate Optical Signals 05.05.2024

The modern world of science and technology is developing rapidly, and every day new methods and technologies appear that open up new prospects for us in various fields. One such innovation is the development by German scientists of a new way to control optical signals, which could lead to significant progress in the field of photonics. Recent research has allowed German scientists to create a tunable waveplate inside a fused silica waveguide. This method, based on the use of a liquid crystal layer, allows one to effectively change the polarization of light passing through a waveguide. This technological breakthrough opens up new prospects for the development of compact and efficient photonic devices capable of processing large volumes of data. The electro-optical control of polarization provided by the new method could provide the basis for a new class of integrated photonic devices. This opens up great opportunities for ... >>

Random news from the Archive pig city 25.10.2020 Atop the forested Mount Yaji, about 64 kilometers northeast of Beijing, a private farming company is building a veritable pig city, a cluster of high-rise residential buildings, or rather industrial farms, designed to house the world's largest herd of pigs. Why build a whole city for pigs, and even on a mountain? It is hoped that Guangxi Yangxiang's six apartment buildings will protect valuable pig stock from the risk of diseases such as African swine fever, which has killed 2018 million animals (half the world's pig population) since 200. The houses are completely isolated, which should prevent infection. One of the buildings will have 13 floors, making it the tallest pigsty in the world. "The multi-storey building has many important advantages," says farm manager Xu Jiajing. "It saves energy and resources. The land is not that big, but you can raise a lot of pigs." The cost of the complex is about 6,5 million dollars. It comes out at $ 2400 per pig, excluding the cost of the animals themselves.

Other interesting news:

▪ Router Netgear R6250, 802.11ac (5G Wi-Fi)

▪ Avalanche of balls

▪ Collision of protons is simulated

▪ Mandatory biometric registration

▪ Bone repair with sound

News feed of science and technology, new electronics

Interesting materials of the Free Technical Library:

▪ section of the site Fundamentals of safe life (OBZhD). Article selection

▪ article The soul must work. Popular expression

▪ article What is a scorpion? Detailed answer

▪ article Movement on industrial premises. Standard instruction on labor protection

▪ article Resonance wavemeter. Encyclopedia of radio electronics and electrical engineering

▪ article Power supply with short circuit protection, 0-12 volts 400 milliamps. Encyclopedia of radio electronics and electrical engineering

Leave your comment on this article:

All languages ​​of this page

Arabic	Hebrew	Polish
Bengali	Hindi	Portuguese
Chinese	Italian	Spanish
English	Japanese	Turkish
French	Korean	Ukrainian
German	Malay	Vietnamese

Home page | Library | Articles | Website map | Site Reviews

www.diagram.com.ua
2000-2024