Rechenweg Elektrotechnik
Study aid: Ohm's law, Bode
Free · In‑App Purchases · Designed for iPad. Not verified for macOS.
From Ohm to Bode to semiconductors: every calculation with the complete step-by-step solution in exam format, plus step-by-step explanations.
Rechenweg Elektrotechnik is your calculator and exam trainer for electrical engineering studies: from direct current and network analysis through complex AC analysis, filters and Bode plots to levels, radio and signals. The app shows the complete step-by-step solution for every problem in exam format, with formula, values inserted, intermediate results and result. It is free for one example per module and available for your own numbers with Pro.
ALL MODULES
• Direct current: Ohm’s law, power and energy, series circuits and parallel circuits, voltage divider and current divider, wire resistance
• Network analysis: Kirchhoff’s laws, mesh and nodal analysis, superposition, equivalent sources and star-delta
• Capacitor and inductor: capacitance and inductance, energy, charging and discharging, time constant τ
• AC with complex numbers: RMS value, phasors, impedance, phasor diagrams, resonant frequency and quality factor
• AC power: real, reactive and apparent power, power factor, power factor correction and three-phase power
• Filters and Bode plots: low-pass and high-pass filters, RC and RL filters, cutoff frequency, transfer function, magnitude and phase response
• Levels and decibels: dB, dBm and dBµV, attenuation and gain in chains, noise power and signal-to-noise ratio
• Radio, transmission and positioning: free-space loss, link budget, Fresnel zone, Shannon capacity, cell planning and trilateration
• Amateur radio exam: technology: calculation questions for classes N, E and A with the full working
• Signals and transmission: sampling theorem, PCM, line codes, modulation, spectrum and FFT, bandwidth and attenuation
• Electronics and semiconductors: diode and Zener diode, transistor as a switch, load line, operational amplifier (op amp) and voltage follower
• Transmission lines: reflection, input impedance, attenuation, fault location, crosstalk
Every module comes with an interactive chart, such as the Bode plot, the phasor diagram or the transistor load line.
PRACTISE AND LEARN
The trainer starts with worked examples, hides steps one by one and finally lets you calculate on your own. A true-or-false trainer checks your understanding with the reason, and the practice exam can follow the layout of a real exam. Hints help you in stages, and typical mistakes are named instead of just marked wrong. The app spaces repetitions with FSRS, and the study plan spreads the material backwards from your exam date. An optional study reminder (at most one a day) and a widget with the countdown to your exam keep you on track.
Every procedure has a step-by-step explanation with formula, approach, common mistakes and an example. You reach it from the topic page and from search.
FREE AND PRO
Free: every calculator with result and formula, one worked example per module with the complete solution path, the trainer's model solutions and the progress overview.
Pro: complete solution path for your own numbers, trainer levels 2 to 4 with generated problems and error diagnosis, exam mode, repetition with FSRS, daily plan and study plan, exam readiness and export of the solution path as PDF. Pro keeps growing: we keep adding new problems and further modules.
Pro is available as a monthly, a semester (6 months) and a yearly subscription. The monthly subscription starts with a trial of 7 days if you have not used it before. The store shows price and term before you buy. The subscription renews automatically unless you cancel at least 24 hours before it ends. You can manage and cancel it any time in your Apple ID settings.
A learning and calculation aid for studying, not for designing real installations and no guarantee of exam success. No account, no advertising: your learning progress stays on your device.
Terms of Use (Apple standard EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/
Privacy: https://kobosil.me/datenschutz/#rechenweg-elektrotechnik
Legal notice: https://kobosil.me/impressum/
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
New: the Transmission lines module with pulse reflectometry, reflection coefficient, input impedance, attenuation, fault location and crosstalk, each with solution path, graphic, trainer and practice exam. Plus microcontroller calculations (LED on a port pin, ADC code from the pin voltage), own pictures for empty screens and many improvements to usability and accessibility.
The developer, kobosil.me Development, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Linked to You
The following data may be collected but it is not linked to your identity:
- Identifiers
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Roman Kobosil
- Size
- 79.8 MB
- Category
- Education
- Compatibility
Requires iOS 16.4 or later.
- iPhone
Requires iOS 16.4 or later. - iPad
Requires iPadOS 16.4 or later. - Mac
Requires macOS 12.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
- English and German
- Age Rating
4+
- 4+
- In-App Purchases
Yes
- Pro semester $12.99
- Pro monthly $3.99
- Pro yearly $24.99
- Copyright
- © 2026 Roman Kobosil