How to connect an analog voltmeter to a computer and highlight it.

Nowadays, high technology can often be found voltmeters / ammeters made in the form of an LCD indicator. But all this does not look as effective as an analog retro - a voltmeter flaunting on the front panel of your case! This article provides an overview and technical performance of mods in retro style.

The voltmeter is made in a traditional style and can work well with some cases. At radio bases, one can often see not only voltmeters, but also ammeters, which can also take place on the 5’25 plug. This voltmeter is capable of measuring DC voltage from 0 to 15 volts. This is what we need, because we will use a voltmeter as a 12 volt monitoring. Let's take a closer look. The lower part of the voltmeter is covered with a plastic cap. This technical maneuver is only for us - we can place a backlight under this cap ...

The more complex the chain, the more connections. If at least one contact is broken ...

When drawing up and installing an electrical circuit, it may be necessary to connect its parts and elements using terminals, clamps, plugs and sockets, thrust and threaded contacts and other special devices, and sometimes just twisting the bare ends of the connecting wires. Even in the simple electric circuit of a flashlight, you will count about a dozen such connections.

And the electrical circuits of household electrical appliances, tape recorders, televisions contain hundreds and even thousands of interconnected parts.

And each of these compounds should not only be mechanically strong, but also provide reliable electrical contact.

It is not so simple at all. If the conductors at the junction are not tightly pressed against each other or if their surface is covered with a film of oxides that conducts poorly electric current, then with an apparent strength of the connection it will be unreliable. And you already know that it is only in one place in the circuit to break the contact, how the current will stop and the device you made will stop working.

How to ensure the strength and reliability of numerous connections of elements and parts in complex electrical circuits? One of the most widely used methods of such a connection is soldering ...

A serious scientific experiment is chaotic, like war. The researcher often does not understand what is happening. The data obtained, as well as information from front-line intelligence, are usually contradictory. Further experiments have to be carried out “by touch” to obtain new facts. But in the end, the picture becomes clearer and then the “backdating” experimenter in the report describes a clear and precise sequence of his steps towards the goal, without mentioning the wrong ones. The main results of the experiments quite often lie not where the scientist was striving. However, the progress report looks like a triumphal procession from one truth to another, whether he wants it or not. Unfortunately, historians of science later work with such materials, which of course affects the quality of their work.

I would like to recall the story of one discovery that happened almost three centuries ago, which is now considered quite natural and taken for granted. Its authors are almost forgotten, but its significance for physics is no less than the voyage of Columbus to geography ...

“The thunder will not strike - the man will not cross himself”, “Do not put off until tomorrow what you can do today”, “Forge the iron while it's hot” - these are famous folk wisdom.

For centuries, people have felt the truth of these expressions on their own skin, regardless of what they were doing - they ate a mammoth in a cave or chopped cabbage at a flea market, planted rye in the steppes of Ukraine or gathered votes in elections ...

In addition to applying these proverbs to certain events, the meaning implied in them can be transferred to entire periods in a person’s life.

He postponed his studies, "put" to work - and the years go by, and self-realization of a person does not occur. As a result, negative consequences are not ruled out - “looked into the glass”, “stepped on a cork” or simply missed the time, which is not enough, how not to hope, then when the “cancer whistles” or “the cock bites” ...

I don't really like formulas. Like any normal person :) They cause me a headache and a desire to throw something into the wall. All my life I tried to stay away from them. And it turned out. But now I became interested in LEDs and realized - there’s no getting anywhere. To get the desired result, you need to understand how it works. Slowly, along the steps, I began to wade through the jungle of lumen, candela, and steradian. Gradually, a picture began to form in my head. And at the same time regret - well, why was there no one to explain it in a simple accessible language? So much time wasted ... I'll try to save you from a headache and explain as much as possible what an LED is and how it works. Well, at the same time I’ll explain a couple of laws of optics :)

The article is dedicated to those who get confused in watts-candela-lumens-suites. And indeed in LEDs. Written by an advanced teapot for beginners dummies ...

Electric meters are subject to periodic verification. According to the "Rules for the Use of Electric and Thermal Energy", the inter-calibration interval should be no more than four years for devices used in the ASKUE system (we will discuss this system later) and at least eight years for local electricity meters. Therefore, according to these standards, electricity meters must be periodically dismantled and attorneys installed instead.

It would seem that there is nothing complicated about this. But imagine that you need to replace the electric meter on a feeder, the disconnection of which is problematic for several reasons. For example, due to the continuity of the process.

Is it possible to make sure that a replacement is made without disconnecting consumers and at the same time in strict accordance with the Safety Rules? ...

Heating cables - a specific type of cable products that convert electrical energy into heat for heating and perform the function of a receiver of electrical energy, rather than a transmission line. Heating cables are significantly different from ordinary cables and wires, the purpose of which is to transmit electrical energy with the least loss and with a slight voltage drop not the line length (usually not more than 5%).

The heating cable is used as heating sections, i.e. segments of a certain length, and at this length there is a complete drop in the applied voltage. Therefore, the heating section should be considered as a conventional receiver of electrical energy (as one of the types of electric heating elements) ...

An ECG is an electrocardiogram, a recording of electrical signals from the heart. The fact that a potential difference arises in the heart upon excitation was shown as early as 1856, during the Dubois-Reymond era. The experiment proving this was set by Kelliker and Müller exactly according to Galvani’s recipe: a nerve running to the frog’s foot was laid on an isolated heart, and this “living voltmeter” responded with a jerking of the paw to each heart beat.

With the advent of sensitive electrical measuring instruments, it became possible to capture the electrical signals of a working heart by applying electrodes not directly to the heart muscle, but to the skin.

In 1887, it was for the first time possible to register a human ECG in this way. This was done by the English scientist A. Waller using a capillary electrometer ...