Electrical, Electronic Engineering, Ecology and Environmental Education & Professional World Portal.

Three-phase AC motor for hermetic refrigeration compressor. Photo, Radoje Jankovic.

Author: Radoje Jankovic

The illustrations are inserted between text.

Here are we.

My educational group in Electrical & Electronic Engineering –  Facebook. Now 4200 over members from up to 110 countries.

White Angel, one of the best fresque in the world is in my Country.


All electrical engineering and electronics with technical and technological disciplines, ecology, environment, environment protection and sustainable development and sustainable living with nature that are all in the very closes relationship.

The ecological and environmental problems are caused mostly by electrical end electronic engineering.


Ecological pollution of air from municipality heating plant. Photo, Radoje Jankovic.
Large capacity oil shipping pump in a oil field. Photo, Radoje Jankovic.


Practice, theory and experiment together!

The distribution table for one multifloor building during fitting. Single core cables 4 x 35 sq. Mme and 3 x 70 sq.mm. Photo from my friend.
Cathodic protection station for pipe line in a oil field. Photo, Radoje Jankovic.

INNOVATIVE EDUCATIONAL MATERIALS, different from others that are spread across many Internet sites. 


We want everyone to find something here for themselves; 

Contractor … 
from areas that process and show you.

Jankovic front the overturned 110 kV tower, during orcanic wind june, 2014. In the Lazarevac municipality. Phto of a friend.

Transmission line loaded with different distances of loads along line.. TS is transformer substation. More details in future article. Drawing Radoje Jankovic.

Ecology. Flowering trees. Photo, Radoje Jankovic,  March 1st, 2016.

Single line diagram of 0,4 switchgears in distribution transformer substations. Typical transformer stations 10 and 20 kV. Voltage 10/0.4 kV.  Applicable for any voltage level. Work by Radoje Jankovic.

Strong wind damaged 110 kV tower. Photo, Radoje Jankovic.

The apparatus for demonstrating magnetic field lines of two air solenoids. Design and construction by Radoje Jankovic


So let’s be the best! 

Why not?

Our intention is:

From expert to the experts, 
From engineer to the engineers, 
From technician to technicians, 
From designer to the designers 
From practitioner to the practitioners, 
From craftsman to the craftsmen, 
From yourselfer  to the yourselfers, 
From hobbyist to the hobbyists, 
From amateur to the amateurs …

One part of my personally library with many technical books, documentation and archive from various technical and ecological fields. Photo, Radoje Jankovic.

Installing LED elements for a information table… Photo, Radoje Jankovic.
Small wind generator , DIY. Photo, Radoje Jankovic.

Jankovic calculated and draw this vector diagram of one AC circuit.
Analogy of electric and water circuit

Linemen in action on the hard terain under winter conditions. Photo of my friend.

„Practical“ electrical engineering too. Photo from my friend.

DIY spherical capacitor for laboratory experiments. Desgin by Radoje Jankovic.

Electrolythic capacitors and other electrical and electronic components… Photo, Radoje Jankovic.

Practical example of Low Voltage network for a village suppying from transformer station ’’A’’. Black numbers are villager’s loads in kW and red numbers are distances from pole to pole. The LV is 3×400/3×230 V, 50 Hz. This or similar arrangement of LV network is applicable anywhere  you like. In one article I will give detailed calculations of LV overhead network. By Radoje Jankovic.

Direct current generator diagram for right rotation direction. Drawing, Radoje Jankovic.

Ecology of plants. What do you can read from this cutted tree?  Photo, Radoje Jankovic.

Typical wood poles from project for distribution networks, LV and HV from 400 V up to 35 kV. May be used anywhere. From Jankovic archive.

One printed circuit board. Photo, Radoje Jankovic.

Some of wires for resistors and  heaters winding …. Photo, Radoje Jankovic.

One of many positions of the biggest rotary excavator working in open pit mine in my municipality. These and other large mining machinery are good for electricity production from coal in the thermal power plants, but, they destroying dozens and dozen villages and complete living infrastructure, ecosystem, arable land, forests, rivers and streams… they are very danger for environment and make big ecological problems, pollution etc.   Photo, Radoje Jankovic.

Combined HV and LV line through my village electrification. Photo, Radoje Jankovic.

One camera in street crossing near a Primary school for video control of traffic. Photo, Radoje Jankovic.

Experimental lab device of NAND logic circuit. Design and made by Radoje Jankovic.

Diagram of all electrical quantities in one series RLC circuit calculated and draw by Radoje Tankovic

DC railway for transporting the coal from coal crushing plant to thermal electric power plant. Voltage is 1200 V.D.C. Photo, Radoje Jankovic.

Complete three line diagram of classical and typical transformer station for electrificacion of small and biger villages from few hundreds up to 3000 of villagers.  Applicable for all distribution medium voltages up to 14 kV. By Radoje Jankovic.

Electrical field in flat-plate capacitor left, and between plane and sphere right.

My friend working in fiber optic cable. Photo of him.

Resistive wire and some winded heater elements…. Photo, Radoje Jankovic.

One practical series RLC circuit. Drawing and calculations by Radoje Jankovic.

Park lighting. Photo Radoje Jankovic.

Hazardous area electrical switchgear in one oil filed. Photo Radoje Jankovic.

Typical plan of overhead line from one project. From Jankovic archive.

Details of cable installations in a steel construction of excavators. Photo, Radoje Jankovic.

For better and ecologically helahier life village roads need be asphalted. Photo, Radoje Jankovic.

Overhead line 10 kV, failure because overloaded line with snow, 7.10.2017.

Typical three line circuit diagram of pole mounted distribution transformer stations for electrification of villages and smaller cities. The standard power of transformers is; 10, 20, and 30 kVA , 10/0.4/0.23 kV. These TS can be used to other voltage levels depending of local distribution company, per example all from 4,16 kV up to 14,5 kV.  From Jankovic archive.

Multilevel building floor distribution board under fitting. Photo my friend.

One of many principal single line diagram of transformer stations for voltage shown in figure. In future I will speaking in more details of various types. Drawing by Radoje Jankovic.

Environmental studies of large open pit coal mine on the nature, ecology and environment in the municipality Lazarevac. The investigations and study by Radoje Jankovic.    

Single line diagram of HV switchgear with three cubicles. First is incoming cubicle, second is supplying a driving motor of one Leonard group, and third is feeder for power transformer. Drawing by Radoje Jankovic.

The portal is intended for: 
–  Hobbyist , 

– Amateurs, 
– Builders, 

– Students,

– Electricians,
– Engineers, 
– Designers, 
– Constructors, 
– Craftsmen, 
– Practitioners, 

– Scientists, 
– Professors, 
– Servicers, 
– Maintenance Experts, 
– Instructors, 
– Contractors, 
– Supervisory Authorities, 
– Innovators, 
and finally people who want knowledge.

Electrical measuring instruments. Analog frequency meter with vibration mechanism. Photo, Radoje Jankovic.
Photovoltaic solar energy in practice. One small solar generator with 2 panels. DIY system. Photo, Radoje Jankovic.




Some of many technical articles categories

DIY Projects

Mixed Test Questions (MTQs)

Illustrated Test Questions (ITQs)

Practical Test Questions (PTQs)

Mixed Questions – Answered (MQA)

Practical Questions – Answered (PQA)

Test Questions For All E&E Professions  

Practical Calculations of All Kind in E&E

Practical Solutions Through Questions & Answers 

Short Lessons

DC Electric Circuits

AC Electric Circuits

Nikola Tesla Patents, Articles…

AC Electric Circuits Library

Mechanical Electrical & Electronic Components

Schemes and Circuits

Photos  from Practice

Practical Electrical Installations

Practical Electrical Engineering

Good Practice in The Electrical Engineering

Solved Problems

Formulae with Details

Mathematics, Basic Elements

Lab Experiments

Your  Workshop/Lab

Basic Electricity Experiments

Basic Electronic Experiments

Higher Electrical Engineering Experiments

Lessons in Electrostatics

Lessons in Electromagnetism

Lessons  in Electricity

Lessons in Electronics

Lessons in  DC

Lessons  in AC

Lessons in Three-phase Systems

Lessons in Electrical and Electronic Measurements

Electrical Projects From Practice

Practical Electronic Projects

Practical Electronic Experiments

Electrical Machines and Drives

Electrical Heating and Equipment

Practical Exercises Electrical Installations

Practical Exercise in Electrical Motors

Practical Exercises in Transformers

Practical Exercises in Motor Drives


Electrical Traction and Equipment

Low Voltage devices and Equipment

Low Voltage (LV) Lines and Networks

Medium Voltage (MV)  Lines and Networks

110/35 kV switchyard, Photo, Radoje Jankovic.

High Voltage (HV), Extra High Voltage (EHV), Ultra High Voltage (UHV) Lines, Switchyards and Switchgears

Ultra High Voltage DC (UHVDC) Lines and Equipment

HV, EHV, UHV, & UHVDC components and equipment

LV, MV, HV, EHV, UHV Surface and Underground Lines

MV, HV, EHV, UHV Transformer substations

Protection of Electrical System

Electrical Networks

Electrical Measurements

Industrial Automation


Optical fibers, 120 nanometer diameter. Photo, radoje Jankovic.
Bird’s life.
Photo, Radoje Jankovic
Medium Voltage (MV) transmission lines.
A-type wood pole for 35 kV OH line.
Photo, Radoje Jankovic.

Electrical field inside the electroscope

Street lighting lamp. Photo, Radoje Jakovic.

One type of female connector. Photo, Radoje Jankovic.
Street lighting.
Installing LED lamp in pole.
Photo, Radoje Jankovic.

 As a student of elementary school, I read in some magazines articles about solar energy and the possibilities of its utilization. At that time, the development of photovoltaic solar cells was in an early stage. Produced are small and only for special purposes and there is talk that may be used for the production of electricity for the practical everyday application. 
I am as student of class VIII, I would imagine that the cells can be utilized for large-scale solar photovoltaic power plants, but by my own ideas I am “designed” this photovoltaic solar power plant shown in the original paper from the school note book A4 form and has everything you need to have one true power, not knowing much about the contemporary the technology is now a reality. 

Electrical Installations

Hazardous Area Installations and Equipment

Lighting and Equipment

Electrical Switchgears

Electrical Materials and Components

Electronic Components

Power Plants

Conductors and Cables

Electrical Tools and Machines

Power Electronics

Relay Protection

Fiber Optic Engineering

Passive solar home complete designed by Radoje Jankovic. Phtovoltaic solar panels used also. Drawing by Radoje Jankovic.

Passive solar home designed by Radoje Jankovic. On south side you can see solar air collector of wall type, desing by Jankovic too. Drawing by Radoje Jankovic.

Passive solar home originally designed by Radoje Jankovic. You may see the solar space. Drawing by Radoje Jankovic.

Jankovic worked out the biological network of natural radiations impacting on the his project of passive solar home. Drawing by Radoje Jankovic.

Near the passive solar home existing one Arthesian weel for drinking water. Jankovic is analyzed  the impact of underground water radiation to the home. Drawing by Radoje Jankovi.

Hot air heating system designed by Radoje Jankovic for passive solar home. Drawing by Radoje Jankovic.

Solar space of passive solar home … sunshine analysis by Radoje Jankovic.

Single line diagram of LV transformer station, 460/220/125 V, 60 Hz, 75 kVA. Drawing by Radoje Jankovic.

One older type of distribution transformer station 10kV/400/230 V, 100 kVA  for villages. Still in use. Photo Radoje Jankovic.

Horizontal cross section of one power transformer. In one article I will give complete design and detailed claculations of this transformer. Drawing by Radoje Jankovic.

IT and Data Networking

UPS and Installations

Batteries & Power Supplies

Emergency Generating Units

Microwave Engineering



Electrical installations in steel constructions.
Three-phase AC driving motor for caterpillar of a large rotary excavator in a open pit mine.
Photo, Radoje Jankovic.

Circular diagram of three phase asynchronous electric motor winding.
Hand-drawn. Do you can today to draw a similar diagram yourself by your hands. Don’t me tell that you have computer! Are you a electrical expert or not? Drawing Radoje Jankovic.
35 kV overhead lines for supplying a large open pit mine. Here is crossing the river.
Photo, Radoje Jankovic.

Combined wood pole of overhead line 35 kV. Photo, Radoje Jankovic.
Three-phase slip-ring motor connection boxes.
Photo, Radoje Jankovic.

Overhead line 35 kV on wooden pole. Photo, Radoje Jankovic.
Three-phase power transformers,
Photo, Radoje Jankovic.

Street lighting with LED lamps, recorded by Radoje Jankovic.
Outdoor crane in a large servicing workshop yard.
Photo, Radoje Jankovic.
Electrical measuring instruments.
Analog AC ammeter.
Photo, Radoje Jankovic.

Ecology and Environment.
I’m worked out this geographical map of village Sakulja in my municipality, which  is complete physically destroyed excavating coal by surface mining / open pit mine during ’90th last century. This is one only document that this village existed over 500 years. This map I’m worked during my  investigation of impact of surface mining to the environment and human. Work, Radoje Jankovic.
Electrical devices.
Electromechanical relay.
Photo, Radoje Jankovic.
LV networks.
LV line for home supplying and street lighting.
Photo, Radoje Jankovic.

Servicing of Electrical Equipment

Servicing and Maintenance of Electric Machines

Servicing and Maintenance of Transformers

Lessons  in Ecology

Lessons  in Environmental Science

Lessons in Sustainable Development

Lessons in Environmental  Geography

220 kV overhead line tower. Photo, Radoje Jankovic.
Jankovic’ innovation of a screwdriver

Lessons in Renewable Energy Resources

Ecological and Environmental Test Question

Articles in Ecology, Environment, Sustainability and Human Life

Ecological and Environmental Practice

Environmental Engineering

Fine leads for various uses in experiments, testings, labs, practice… DIY and photo by Radoje Jankovic.

Concrete pole mounted three-phase power transformer for villages electrification.  Voltage level 10 kV/0,4/023 kV,  50 kVA. Photo, Radoje Jankovic.
Fine conductors.
You no need to buying costly leads for your workshop, lab, or experimental purposes. You can find a lot of fine insulated wires for small money and make in DIY every kind of test lead.
Photo, Radoje Jankovic.
For your electricity and electronic experiments in breadboard you no need to buying extra wires for your connection of circuits. You may find these very fine insulated conductors in various colors and yourself make every type of connection wires for your breadboard.
Photo, Radoje Jankovic.

Twelve Sources of Electric Power

1.Conventional Power plants

2. Coal Gasification and Liquefaction

3. Pico, Micro and Small Scale Hydro Power Plants (PMSSHPPs)

4. Solar Thermal Power Plants (STPPs)

5. Photovoltaic Solar Power Plants (PVSPPs)

6. Wind Energy Power Plants (WEPPs)

7. Geothermal Power Plants (GPPs)

8. Hydrogen Power Plants (HPPs)

 9. Biomass Energy Plants; a) Forest, b) Vegetation, c) Animal refuse

10. Ocean Energy; a) Tidal Power, b) Wave Power, c) Ocean thermal gradient power

11. Magneto Hydro-Dynamic or Fluid Dynamic Plants

12. Nuclear Power Plants (NPP)

One of driving electric motor for caterpillar in a large excavators in a open pit mine. Photo Radoje Jankovic.

Making joint in damaged  underground cable. Photo from my friend.

Experimental  lab diode logic AND circuit. Design and made by Radoje Jankovic.

From electrician practice. Photo from my friend.

Street lighting pole foundation with cables and grounding Fe/Zn tape.

Labs working model of Schmitt Trigger for experiments. Design and made by Radoje Jankovic.
When you want to make something, you must be professional. Not a amateur.

Apparatus for demonstrating the magnetic field of bar permanent magnet, design and construction by Radoje Jankovic.

Ecology of birds. Photo, Radoje Jankovic.
Winter overhead transmission line corridor
Lineman’s team in the winter conditions of working
Electrical Installations
Underground cable installations
Hydroelectric power plant under construction
Rotational electric machines
Three phase asynchronous electric motor, 2400 kW, 6000 V, 50 Hz.
Trofazni asinhroni motor snage 2400 kW, 6000 V, 50 Hz
Power cables, 1×1000 mm2, single core

Founder and owner: Radoje-Rade Jankovic

Electrician, Technician, Electrical Engineer, PhD, Ecologist, Environmentalist, Engineering Writer, Designer, Educator…

Massive practical experience over 40 years in almost  all electrical engineering fields as Electrician, Technician, Field Engineer, Site Supervisor, Site Manager, Contractor, Maintenance Electrician, Engineer, Designer, Ecologist, Environmentalist, Technical Writer.

Familiar with IEC, DIN, VDE, ASA, GOST  Standards.

Editor-in-chief EEEEEPEW-Portal