Coaxial cable loss calculator
About
This calculator lets you work out power losses in coaxial cables and connectors at different frequencies. You can add various types of cable, connectors and attenuators in order to model your actual antenna system.
The calculator includes the characteristics of popular Ukrainian and foreign cables.
| Вузол | Заголовок | Довжина, м | Дії |
|---|---|---|---|
| Жодного вузла не додано. | |||
| Частота | Втрати, дБ | Втрати, % | Вихідна потужність, Вт |
|---|---|---|---|
| Заповніть форму вище, щоб отримати розрахунки. | |||
Notes
- System components: add cables, connectors and attenuators in the order they are connected.
- Cable length: given in metres to the nearest centimetre (0.01 m).
- Number of connectors: given as a whole number (for example, 2 connectors).
- Loss calculation: linear interpolation between known frequencies is used.
- Colour coding of the results:
- 🟢 Green: losses below 50% (acceptable)
- 🟡 Yellow: losses of 50–80% (needs attention)
- 🔴 Red: losses above 80% (critical)
- Cable types:
- RG-58: thin cable for HF/VHF (50 Ω)
- RG-8: thick cable for HF (50 Ω)
- LMR-400: low-loss cable for VHF/UHF (50 Ω)
- RG-213: thick general-purpose cable (50 Ω)
- RG-174: very thin cable for UHF (50 Ω)
- RK 50: Soviet and Ukrainian cables (50 Ω)
- 3D-FB: semi-rigid cable for UHF (50 Ω)
- Conductors:
- Solid core: better characteristics at high frequencies
- Stranded: more flexible, worse losses at UHF
- Calculation frequencies: 1.9, 3.75, 7.15, 14.15, 27.5, 52, 145, 435 MHz
- Accuracy: the results are approximate and depend on the quality of the cable and the installation
- Recommendations:
- Use the shortest cables you can
- Keep the number of connectors to a minimum
- For VHF/UHF use LMR-400 or equivalent cable
- Check the SWR of the system after installation
Sources of the data
The characteristics of the cables and connectors are taken from:
- Manufacturers' technical documentation
- Measurements made by radio amateurs
- Catalogues of Ukrainian suppliers
- International standards
Calculator by UR3PKI
The most recent versions are available on the author's site: CYBERDEV.SPACE - coaxial cable loss calculator