diff --git a/RFG_ADC_dataplotter.py b/RFG_ADC_dataplotter.py
index 88ed519..3a4c964 100755
--- a/RFG_ADC_dataplotter.py
+++ b/RFG_ADC_dataplotter.py
@@ -347,7 +347,7 @@ class SweepReader(threading.Thread):
             dt_ms = (now - self._last_sweep_ts) * 1000.0
         self._last_sweep_ts = now
         self._n_valid_hist.append((now, n_valid_cur))
-        while self._n_valid_hist and (now - self._n_valid_hist[0][0]) > 10.0:
+        while self._n_valid_hist and (now - self._n_valid_hist[0][0]) > 1.0:
             self._n_valid_hist.popleft()
         if self._n_valid_hist:
             n_valid = float(sum(v for _t, v in self._n_valid_hist) / len(self._n_valid_hist))