Calculating Exact Feed Point Locations

Date: 2026-01-12

• End-fed long wires have high impedance; center feed is low impedance.
• For off-center feed, choose a ratio that yields 200 to 3000 ohms.
• Use current distribution: feed where current is not at a null.
• For L = 1/2 lambda, center feed is typical; for 1 lambda, avoid center.
• Model impedance vs position and choose a point for your transformer.
• Verify with VNA or tuner measurements in the final installation.