Why Is 50 Ohms the Standard?
The Commercial Choice
- Lowest loss occurs at ~77 Ω (air dielectric) — or ~51 Ω with solid polyethylene
- Maximum power handling occurs at ~30 Ω
- 50 Ω is the compromise — reasonable loss and reasonable power handling
- Commercial/military systems need both: high power, long duty cycles, long runs
- The entire industry ecosystem standardized around this choice
The Amateur Reality
- Most of us run 100 watts or less — power handling is a non-issue
- At amateur power levels, voltage stress in RG-6 is nowhere near breakdown
- Most common amateur antennas don't naturally present 50 Ω
- A dipole at typical heights is often closer to 75 Ω than to 50 Ω
- Our priorities: SWR, cost, availability, low loss — not kilowatt power handling