<div id="resultArea" class="result" style="display: none;"> <div style="font-weight: 600;">📌 Inset from edge</div> <div class="result-value" id="insetValue">—</div> <div id="insetUnit"></div> </div>
function showError(msg) let errDiv = document.getElementById('errorMsg'); errDiv.innerHTML = msg; errDiv.style.display = 'block'; document.getElementById('resultArea').style.display = 'none'; inset feed calculator
<hr> <div class="note"> <strong>Formula:</strong> y₀ = (L/π) · arccos(√(Z_feed / R_edge))<br> Valid when Z_feed ≤ R_edge. Typical matching range: 50Ω feed to 150–250Ω edge. </div> </div> div id="resultArea" class="result" style="display: none
<div class="input-group"> <label>🔌 Feed line impedance, Z_feed (Ω)</label> <input type="number" id="zfeed" placeholder="e.g., 50" value="50"> <div class="hint">Usually 50 Ω for standard systems</div> </div> div style="font-weight: 600
[ y_0 = \fracL\pi \cdot \cos^-1\left( \sqrt \fracZ_feedR_edge \right) ]
For a rectangular patch antenna with an inset feed: