diff --git a/src/trx-client/trx-frontend/trx-frontend-http/assets/web/app.js b/src/trx-client/trx-frontend/trx-frontend-http/assets/web/app.js
index b478397..aec85e1 100644
--- a/src/trx-client/trx-frontend/trx-frontend-http/assets/web/app.js
+++ b/src/trx-client/trx-frontend/trx-frontend-http/assets/web/app.js
@@ -241,6 +241,9 @@ function render(update) {
       freqEl.value = formatFreq(update.status.freq.hz);
     }
     window.ft8BaseHz = update.status.freq.hz;
+    if (window.updateFt8RfDisplay) {
+      window.updateFt8RfDisplay();
+    }
   }
   if (!modeDirty && update.status && update.status.mode) {
     const mode = normalizeMode(update.status.mode);
@@ -785,21 +788,33 @@ window.aprsMapAddStation = function(call, lat, lon, info, symbolTable, symbolCod
   }
 };
 
-function maidenheadToLatLon(grid) {
+function maidenheadToBounds(grid) {
   if (!grid || grid.length < 4) return null;
   const g = grid.toUpperCase();
   const A = "A".charCodeAt(0);
-  const lon = (g.charCodeAt(0) - A) * 20 - 180 + (parseInt(g[2], 10) * 2) + 1;
-  const lat = (g.charCodeAt(1) - A) * 10 - 90 + (parseInt(g[3], 10) * 1) + 0.5;
-  let lonAdj = lon;
-  let latAdj = lat;
+  const fieldLon = (g.charCodeAt(0) - A) * 20 - 180;
+  const fieldLat = (g.charCodeAt(1) - A) * 10 - 90;
+  const squareLon = parseInt(g[2], 10) * 2;
+  const squareLat = parseInt(g[3], 10) * 1;
+
+  let lon = fieldLon + squareLon;
+  let lat = fieldLat + squareLat;
+  let lonSpan = 2;
+  let latSpan = 1;
+
   if (g.length >= 6) {
     const subLon = (g.charCodeAt(4) - A) * (5 / 60);
     const subLat = (g.charCodeAt(5) - A) * (2.5 / 60);
-    lonAdj += subLon - (5 / 120);
-    latAdj += subLat - (2.5 / 120);
+    lon += subLon;
+    lat += subLat;
+    lonSpan = 5 / 60;
+    latSpan = 2.5 / 60;
   }
-  return { lat: latAdj, lon: lonAdj };
+
+  return [
+    [lat, lon],
+    [lat + latSpan, lon + lonSpan],
+  ];
 }
 
 function applyMapFilter() {
@@ -816,11 +831,14 @@ function applyMapFilter() {
 window.ft8MapAddLocator = function(message, grid) {
   if (!aprsMap) initAprsMap();
   if (!aprsMap) return;
-  const loc = maidenheadToLatLon(grid);
-  if (!loc) return;
+  const bounds = maidenheadToBounds(grid);
+  if (!bounds) return;
   const popupContent = `<b>${grid}</b><br>${message}`;
-  const marker = L.circleMarker([loc.lat, loc.lon], {
-    radius: 5, color: "#ffb020", fillColor: "#ffb020", fillOpacity: 0.85
+  const marker = L.rectangle(bounds, {
+    color: "#ffb020",
+    weight: 1,
+    fillColor: "#ffb020",
+    fillOpacity: 0.25,
   }).addTo(aprsMap).bindPopup(popupContent);
   marker.__trxType = "ft8";
   mapMarkers.add(marker);
diff --git a/src/trx-client/trx-frontend/trx-frontend-http/assets/web/index.html b/src/trx-client/trx-frontend/trx-frontend-http/assets/web/index.html
index 4a1e62c..5e7b800 100644
--- a/src/trx-client/trx-frontend/trx-frontend-http/assets/web/index.html
+++ b/src/trx-client/trx-frontend/trx-frontend-http/assets/web/index.html
@@ -165,6 +165,7 @@
         <div class="ft8-controls">
           <button id="ft8-decode-toggle-btn" type="button">Enable FT8</button>
           <button id="ft8-clear-btn" type="button">Clear</button>
+          <input id="ft8-filter" class="ft8-filter" type="text" placeholder="Filter (e.g. CQ, DL4)" />
           <small id="ft8-status" style="color:var(--text-muted);">Waiting for server decode</small>
         </div>
         <div class="ft8-header">
diff --git a/src/trx-client/trx-frontend/trx-frontend-http/assets/web/plugins/ft8.js b/src/trx-client/trx-frontend/trx-frontend-http/assets/web/plugins/ft8.js
index 61a6f1c..962edb8 100644
--- a/src/trx-client/trx-frontend/trx-frontend-http/assets/web/plugins/ft8.js
+++ b/src/trx-client/trx-frontend/trx-frontend-http/assets/web/plugins/ft8.js
@@ -1,7 +1,9 @@
 // --- FT8 Decoder Plugin (server-side decode) ---
 const ft8Status = document.getElementById("ft8-status");
 const ft8MessagesEl = document.getElementById("ft8-messages");
+const ft8FilterInput = document.getElementById("ft8-filter");
 const FT8_MAX_MESSAGES = 200;
+let ft8FilterText = "";
 
 function fmtTime(tsMs) {
   if (!tsMs) return "--:--:--";
@@ -11,13 +13,17 @@ function fmtTime(tsMs) {
 function renderFt8Row(msg) {
   const row = document.createElement("div");
   row.className = "ft8-row";
+  const rawMessage = (msg.message || "").toString();
+  row.dataset.message = rawMessage.toUpperCase();
+  row.dataset.offsetHz = Number.isFinite(msg.freq_hz) ? String(msg.freq_hz) : "";
   const snr = Number.isFinite(msg.snr_db) ? msg.snr_db.toFixed(1) : "--";
   const dt = Number.isFinite(msg.dt_s) ? msg.dt_s.toFixed(2) : "--";
   const baseHz = Number.isFinite(window.ft8BaseHz) ? window.ft8BaseHz : null;
   const rfHz = Number.isFinite(msg.freq_hz) && Number.isFinite(baseHz) ? (baseHz + msg.freq_hz) : null;
   const freq = Number.isFinite(rfHz) ? rfHz.toFixed(0) : "--";
-  const renderedMessage = renderFt8Message(msg.message || "");
+  const renderedMessage = renderFt8Message(rawMessage);
   row.innerHTML = `<span class="ft8-time">${fmtTime(msg.ts_ms)}</span><span class="ft8-snr">${snr}</span><span class="ft8-dt">${dt}</span><span class="ft8-freq">${freq}</span><span class="ft8-msg">${renderedMessage}</span>`;
+  applyFt8FilterToRow(row);
   return row;
 }
 
@@ -81,6 +87,44 @@ function isAlphaNum(ch) {
   return /[A-Za-z0-9]/.test(ch);
 }
 
+function applyFt8FilterToRow(row) {
+  if (!ft8FilterText) {
+    row.style.display = "";
+    return;
+  }
+  const message = row.dataset.message || "";
+  row.style.display = message.includes(ft8FilterText) ? "" : "none";
+}
+
+function applyFt8FilterToAll() {
+  const rows = ft8MessagesEl.querySelectorAll(".ft8-row");
+  rows.forEach((row) => applyFt8FilterToRow(row));
+}
+
+function updateFt8RowRf(row) {
+  const freqEl = row.querySelector(".ft8-freq");
+  if (!freqEl) return;
+  const baseHz = Number.isFinite(window.ft8BaseHz) ? window.ft8BaseHz : null;
+  const offset = row.dataset.offsetHz ? Number(row.dataset.offsetHz) : NaN;
+  if (Number.isFinite(baseHz) && Number.isFinite(offset)) {
+    freqEl.textContent = (baseHz + offset).toFixed(0);
+  } else {
+    freqEl.textContent = "--";
+  }
+}
+
+window.updateFt8RfDisplay = function() {
+  const rows = ft8MessagesEl.querySelectorAll(".ft8-row");
+  rows.forEach((row) => updateFt8RowRf(row));
+};
+
+if (ft8FilterInput) {
+  ft8FilterInput.addEventListener("input", () => {
+    ft8FilterText = ft8FilterInput.value.trim().toUpperCase();
+    applyFt8FilterToAll();
+  });
+}
+
 document.getElementById("ft8-decode-toggle-btn").addEventListener("click", async () => {
   try { await postPath("/toggle_ft8_decode"); } catch (e) { console.error("FT8 toggle failed", e); }
 });
diff --git a/src/trx-client/trx-frontend/trx-frontend-http/assets/web/style.css b/src/trx-client/trx-frontend/trx-frontend-http/assets/web/style.css
index 4994259..1d4a3c7 100644
--- a/src/trx-client/trx-frontend/trx-frontend-http/assets/web/style.css
+++ b/src/trx-client/trx-frontend/trx-frontend-http/assets/web/style.css
@@ -224,6 +224,7 @@ small { color: var(--text-muted); }
 .aprs-pos:hover { text-decoration: underline; }
 .aprs-byte { color: var(--accent-yellow); background: rgba(255, 214, 0, 0.12); border: 1px solid rgba(255, 214, 0, 0.25); border-radius: 4px; padding: 0 0.2rem; margin: 0 0.1rem; font-size: 0.78em; }
 .ft8-controls { display: flex; gap: 0.6rem; align-items: center; margin-bottom: 0.75rem; }
+.ft8-filter { flex: 1; min-width: 10rem; }
 .ft8-header { display: flex; gap: 0.6rem; font-size: 0.75rem; text-transform: uppercase; letter-spacing: 0.06em; color: var(--text-muted); border-bottom: 1px solid var(--border); padding: 0 0 0.35rem 0; margin-bottom: 0.35rem; }
 #ft8-messages { max-height: 360px; overflow-y: auto; border: 1px solid var(--border-light); border-radius: 6px; background: var(--input-bg); font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace; font-size: 0.85rem; padding: 0.35rem 0.5rem; }
 .ft8-row { display: flex; gap: 0.6rem; line-height: 1.4; border-bottom: 1px solid var(--border); padding: 0.25rem 0; }