diff --git a/src/trx-client/src/config.rs b/src/trx-client/src/config.rs
index 43f603a..60228d8 100644
--- a/src/trx-client/src/config.rs
+++ b/src/trx-client/src/config.rs
@@ -257,7 +257,7 @@ impl Default for HttpFrontendConfig {
             default_rig_id: None,
             initial_map_zoom: 10,
             spectrum_coverage_margin_hz: 50_000,
-            spectrum_usable_span_ratio: 1.0,
+            spectrum_usable_span_ratio: 0.92,
             show_sdr_gain_control: true,
             auth: HttpAuthConfig::default(),
         }
@@ -477,7 +477,7 @@ impl ClientConfig {
                     default_rig_id: Some("hf".to_string()),
                     initial_map_zoom: 10,
                     spectrum_coverage_margin_hz: 50_000,
-                    spectrum_usable_span_ratio: 1.0,
+                    spectrum_usable_span_ratio: 0.92,
                     show_sdr_gain_control: true,
                     auth: HttpAuthConfig {
                         enabled: false,
@@ -579,7 +579,7 @@ mod tests {
         assert_eq!(config.frontends.http.port, 8080);
         assert_eq!(config.frontends.http.initial_map_zoom, 10);
         assert_eq!(config.frontends.http.spectrum_coverage_margin_hz, 50_000);
-        assert_eq!(config.frontends.http.spectrum_usable_span_ratio, 1.0);
+        assert_eq!(config.frontends.http.spectrum_usable_span_ratio, 0.92);
         assert_eq!(config.frontends.rigctl.port, 4532);
         assert!(config.frontends.http_json.enabled);
         assert_eq!(config.frontends.http_json.port, 0);
diff --git a/src/trx-client/trx-frontend/src/lib.rs b/src/trx-client/trx-frontend/src/lib.rs
index 764ba31..6e7cbd5 100644
--- a/src/trx-client/trx-frontend/src/lib.rs
+++ b/src/trx-client/trx-frontend/src/lib.rs
@@ -214,7 +214,7 @@ impl FrontendRuntimeContext {
             http_show_sdr_gain_control: true,
             http_initial_map_zoom: 10,
             http_spectrum_coverage_margin_hz: 50_000,
-            http_spectrum_usable_span_ratio: 1.0,
+            http_spectrum_usable_span_ratio: 0.92,
             remote_active_rig_id: Arc::new(Mutex::new(None)),
             remote_rigs: Arc::new(Mutex::new(Vec::new())),
             owner_callsign: None,
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 4a2a19b..3c9d2c8 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
@@ -1167,7 +1167,7 @@ function effectiveSpectrumCoverageSpanHz(sampleRateHz) {
   const sampleRate = Number(sampleRateHz);
   if (!Number.isFinite(sampleRate) || sampleRate <= 0) return 0;
   // Keep a guard band at the spectrum edges; practical usable span is slightly smaller.
-  const ratio = Number.isFinite(spectrumUsableSpanRatio) ? spectrumUsableSpanRatio : 1.0;
+  const ratio = Number.isFinite(spectrumUsableSpanRatio) ? spectrumUsableSpanRatio : 0.92;
   return sampleRate * Math.max(0.01, Math.min(1.0, ratio));
 }
 
@@ -1652,7 +1652,7 @@ let serverLat = null;
 let serverLon = null;
 let initialMapZoom = 10;
 let spectrumCoverageMarginHz = 50_000;
-let spectrumUsableSpanRatio = 1.0;
+let spectrumUsableSpanRatio = 0.92;
 
 function updateFooterBuildInfo() {
   const serverEl = document.getElementById("footer-server-build");