diff --git a/src/emucore/tia/PaddleReader.cxx b/src/emucore/tia/PaddleReader.cxx
index 2e37413a0..e8839b7a8 100644
--- a/src/emucore/tia/PaddleReader.cxx
+++ b/src/emucore/tia/PaddleReader.cxx
@@ -83,17 +83,17 @@ void PaddleReader::setConsoleTiming(ConsoleTiming consoleTiming)
   myConsoleTiming = consoleTiming;
 
   myClockFreq = myConsoleTiming == ConsoleTiming::ntsc ? 60 * 228 * 262 : 50 * 228 * 312;
-  myUThresh = USUPP * (1. - exp(-TRIPPOINT_LINES * 228 / myClockFreq  / (RPOT + R0) / C));
+  myUThresh = U_SUPP * (1. - exp(-TRIPPOINT_LINES * 228 / myClockFreq  / (R_POT + R0) / C));
 }
 
 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 void PaddleReader::updateCharge(uInt64 timestamp)
 {
   if (myValue >= 0 && !myIsDumped)
-    myU = USUPP * (1 - (1 - myU / USUPP) *
-      exp(-static_cast<double>(timestamp - myTimestamp) / (myValue * RPOT + R0) / C / myClockFreq));
+    myU = U_SUPP * (1 - (1 - myU / U_SUPP) *
+      exp(-static_cast<double>(timestamp - myTimestamp) / (myValue * R_POT + R0) / C / myClockFreq));
   else
-    myU *= exp(-static_cast<double>(timestamp - myTimestamp) / R0 / C / myClockFreq);
+    myU *= exp(-static_cast<double>(timestamp - myTimestamp) / (myIsDumped ? R_DUMP : R0) / C / myClockFreq);
 
   myTimestamp = timestamp;
 }
diff --git a/src/emucore/tia/PaddleReader.hxx b/src/emucore/tia/PaddleReader.hxx
index 18b2468db..bd3ab0728 100644
--- a/src/emucore/tia/PaddleReader.hxx
+++ b/src/emucore/tia/PaddleReader.hxx
@@ -67,8 +67,9 @@ class PaddleReader : public Serializable
     static constexpr double
       R0 = 1.8e3,
       C = 68e-9,
-      RPOT = 1e6,
-      USUPP = 5;
+      R_POT = 1e6,
+      R_DUMP = 50,
+      U_SUPP = 5;
 
     static constexpr double TRIPPOINT_LINES = 379;