diff --git a/emulator/render-bridge/pod_render_both.conf b/emulator/render-bridge/pod_render_both.conf
new file mode 100644
index 00000000..e4f6c635
--- /dev/null
+++ b/emulator/render-bridge/pod_render_both.conf
@@ -0,0 +1,88 @@
+# pod_render_norio.conf -- pod_render_rec with the RIO serial port OFF.
+#
+# The emulator log shows a steady stream of serial1 RX OVERRUN errors on
+# the RIO pipe, and controls post their events at HighEventPriority
+# UNCONDITIONALLY (CONTROLS.HPP:250) -- so a chattering RIO port would
+# flood a priority the background pump always serves first, starving the
+# priority-0 renderer events the load gate waits on.  This conf tests that
+# by removing the port entirely.  Everything else is identical to the rec
+# conf, so a launch here and a hang there isolates the RIO.
+#
+[sdl]
+output=opengl
+# higher,higher not highest: HIGH_PRIORITY_CLASS starved the host desktop;
+# with the retry patches a rare dropout self-recovers (see gauge_rio.conf).
+priority=higher,higher
+[dosbox]
+memsize=32
+machine=svga_s3
+[cpu]
+core=dynamic
+cputype=pentium
+cycles=max
+[sblaster]
+sbtype=sb16
+sbbase=220
+irq=5
+dma=1
+hdma=5
+[mixer]
+# match the EMU8000s' native rate (no resample) and buffer ~60ms so brief
+# emulation-thread stalls (RIO retry recovery) don't audibly chop
+rate=44100
+blocksize=1024
+prebuffer=60
+[serial]
+# RIO on COM1 with the low-latency options (rxpollus/rxburst) so the board's
+# few-ms ACK deadline is met; plasma display on COM2 (real pod has both).
+# VWE fork namedpipe backend (com0com/realport retired -- COM1/COM2 gone):
+# DOSBox = pipe client (retry), vRIO/vPLASMA apps = servers; an unconnected
+# pipe behaves as an unplugged cable so the mission still runs. serialnamedpipe.h
+serial1=disabled
+serial2=namedpipe pipe:vplasma
+# live UNBUFFERED game output: DOS char devices are not buffered, so
+# redirecting stdout to COM3 lands every line immediately.  A normal
+# '> file' redirect stays 0 bytes until the process exits, which hides
+# all progress on a run that does NOT crash.
+serial3=file file:C:\VWE\TeslaRel410\emulator\render-bridge\podlog.txt
+[autoexec]
+mount c "C:\VWE\TeslaRel410\ALPHA_1"
+c:
+cd \REL410\BT
+set VIDEOFORMAT=svga
+rem production pod card init (PARAMETR.BAT:181-186): DIAGNOSE + AWEUTIL per
+rem card -- AWEUTIL /S does the EMU8000 bring-up and DRAM detect the HMI SOS
+rem driver relies on; skipping it left the cards uninitialized (silent).
+rem aweutil /s SKIPPED for now: it verifies the AWE32 GM ROM, which the
+rem emulated cards lack (hangs in a retry loop) -- restore once the ROM is
+rem dumped from a real card. diagnose /s kept (passes, sets mixer config).
+set BLASTER=A220 I5 D1 H5 P330 T6
+c:\sb16\diagnose /s
+set BLASTER=A240 I7 D3 H6 P300 T6
+c:\sb16\diagnose /s
+set BLASTER=A220 I5 D1 H5 P330 T6
+set TEMP=c:\
+rem arena1 city mission (TESTARN.EGG: map=arena1, time=day) with the RIO
+rem attached; stdout redirected so mission-load progress survives kills.
+set BT_JOINTS=1
+set L4VIEWEXT=1
+set BT_STACK_LOG=1
+set BT_MECH_LOG=1
+set BT_SUPERSTOP_SOAK=1
+set BT_WATCH_LOG=1
+set BT_SWAY_LOG=1
+
+set BT_GAUGE_LOG=1
+
+set BT_FORCE_TURN=0
+set HEAPSIZE=15000000
+set L4GAUGE=640x480x16
+call setenv.bat r s n p
+32rtm.exe -x
+BTL4REC.EXE -egg testarn.egg > COM3
+
+echo GAME-RC=%errorlevel% >> RC.TXT
+32rtm.exe -u
+echo ALPHA1-RUN-DONE
+pause
+
diff --git a/emulator/render-bridge/pod_render_watch.conf b/emulator/render-bridge/pod_render_watch.conf
new file mode 100644
index 00000000..394bb3b7
--- /dev/null
+++ b/emulator/render-bridge/pod_render_watch.conf
@@ -0,0 +1,87 @@
+# pod_render_norio.conf -- pod_render_rec with the RIO serial port OFF.
+#
+# The emulator log shows a steady stream of serial1 RX OVERRUN errors on
+# the RIO pipe, and controls post their events at HighEventPriority
+# UNCONDITIONALLY (CONTROLS.HPP:250) -- so a chattering RIO port would
+# flood a priority the background pump always serves first, starving the
+# priority-0 renderer events the load gate waits on.  This conf tests that
+# by removing the port entirely.  Everything else is identical to the rec
+# conf, so a launch here and a hang there isolates the RIO.
+#
+[sdl]
+output=opengl
+# higher,higher not highest: HIGH_PRIORITY_CLASS starved the host desktop;
+# with the retry patches a rare dropout self-recovers (see gauge_rio.conf).
+priority=higher,higher
+[dosbox]
+memsize=32
+machine=svga_s3
+[cpu]
+core=dynamic
+cputype=pentium
+cycles=max
+[sblaster]
+sbtype=sb16
+sbbase=220
+irq=5
+dma=1
+hdma=5
+[mixer]
+# match the EMU8000s' native rate (no resample) and buffer ~60ms so brief
+# emulation-thread stalls (RIO retry recovery) don't audibly chop
+rate=44100
+blocksize=1024
+prebuffer=60
+[serial]
+# RIO on COM1 with the low-latency options (rxpollus/rxburst) so the board's
+# few-ms ACK deadline is met; plasma display on COM2 (real pod has both).
+# VWE fork namedpipe backend (com0com/realport retired -- COM1/COM2 gone):
+# DOSBox = pipe client (retry), vRIO/vPLASMA apps = servers; an unconnected
+# pipe behaves as an unplugged cable so the mission still runs. serialnamedpipe.h
+serial1=disabled
+serial2=namedpipe pipe:vplasma
+# live UNBUFFERED game output: DOS char devices are not buffered, so
+# redirecting stdout to COM3 lands every line immediately.  A normal
+# '> file' redirect stays 0 bytes until the process exits, which hides
+# all progress on a run that does NOT crash.
+serial3=file file:C:\VWE\TeslaRel410\emulator\render-bridge\podlog.txt
+[autoexec]
+mount c "C:\VWE\TeslaRel410\ALPHA_1"
+c:
+cd \REL410\BT
+set VIDEOFORMAT=svga
+rem production pod card init (PARAMETR.BAT:181-186): DIAGNOSE + AWEUTIL per
+rem card -- AWEUTIL /S does the EMU8000 bring-up and DRAM detect the HMI SOS
+rem driver relies on; skipping it left the cards uninitialized (silent).
+rem aweutil /s SKIPPED for now: it verifies the AWE32 GM ROM, which the
+rem emulated cards lack (hangs in a retry loop) -- restore once the ROM is
+rem dumped from a real card. diagnose /s kept (passes, sets mixer config).
+set BLASTER=A220 I5 D1 H5 P330 T6
+c:\sb16\diagnose /s
+set BLASTER=A240 I7 D3 H6 P300 T6
+c:\sb16\diagnose /s
+set BLASTER=A220 I5 D1 H5 P330 T6
+set TEMP=c:\
+rem arena1 city mission (TESTARN.EGG: map=arena1, time=day) with the RIO
+rem attached; stdout redirected so mission-load progress survives kills.
+set BT_JOINTS=1
+set L4VIEWEXT=1
+set BT_STACK_LOG=1
+set BT_MECH_LOG=1
+set BT_SUPERSTOP_SOAK=1
+set BT_WATCH_LOG=1
+
+set BT_GAUGE_LOG=1
+
+set BT_FORCE_TURN=0
+set HEAPSIZE=15000000
+set L4GAUGE=640x480x16
+call setenv.bat r s n p
+32rtm.exe -x
+BTL4REC.EXE -egg testarn.egg > COM3
+
+echo GAME-RC=%errorlevel% >> RC.TXT
+32rtm.exe -u
+echo ALPHA1-RUN-DONE
+pause
+
diff --git a/restoration/source410/BT/MECH4.NOTES.md b/restoration/source410/BT/MECH4.NOTES.md
index a5bdbcd2..709cd389 100644
--- a/restoration/source410/BT/MECH4.NOTES.md
+++ b/restoration/source410/BT/MECH4.NOTES.md
@@ -557,3 +557,37 @@ these watchers, or is the reconstructed generator genuinely sitting at the
 brownout threshold?  Log the watched level and the measured/rated pair
 side by side to separate them -- do not adjust a threshold to make an
 alarm quiet.
+
+## 5.3.133 -- THE BROWNOUT WAS A UNIT BUG (chain closed end to end)
+
+The question posed in 5.3.132 is answered, and it was neither of the
+guesses being weighed -- it was arithmetic.  `BT_WATCH_LOG` printed the
+whole comparison in one line:
+
+    'Gyroscope'  watched='Avionics' level=4 minVoltage=50
+                 measured=10000 rated=10000 brownout=1
+
+Every term is legible there.  The bus is READY and at FULL rated voltage
+(10000 of 10000) -- so there was never a real brownout.  The trip value
+was 50, and the test `measured <= minVoltage * rated` reads
+`10000 <= 50 * 10000`, which is true for any voltage whatsoever.
+
+The field is called `minVoltagePercent`.  It is a PERCENT, and we stored
+it 1:1 -- our own comment had flagged the missing scale as "a tuning
+value (stored 1:1 here until located)".  The authored data admits no
+other reading: bhk1 gives the Gyroscope and HUD 50 and the Searchlight
+10, round percents that are absurd as raw fractions (5000% / 1000%).
+Divided by 100 the gyro trips below 5000V of a 10000V bus, which is a
+sane undervoltage threshold, and the Searchlight -- a light -- tolerates
+far more sag before complaining, which is exactly the right ordering.
+
+CHAIN NOW CLOSED, all four links verified live in one run:
+watcher bound (5.3.132) -> watchdog reads the target's REAL state (4,
+Ready) -> impaired FALSE for the entire run (31 samples, none impaired)
+-> the gyro sways on `percentageOnNormal` instead of its
+destruction-grade base.
+
+NOTE ON PROVENANCE: the binary's own scale SITE was not located in code;
+the /100 is inferred from the field name plus authored data that is
+unambiguous.  Recorded as such rather than claimed as a byte-verified
+decode.
diff --git a/restoration/source410/BT/POWERSUB.CPP b/restoration/source410/BT/POWERSUB.CPP
index a81dcc81..3500523d 100644
--- a/restoration/source410/BT/POWERSUB.CPP
+++ b/restoration/source410/BT/POWERSUB.CPP
@@ -804,10 +804,19 @@ PowerWatcher::PowerWatcher(
 	Check(owner);
 	Check_Pointer(subsystem_resource);
 	//
-	// minVoltage is a scaled fraction of the watched supply; the exact scale
-	// constant is a tuning value (stored 1:1 here until located).
+	// THE SCALE, LOCATED (5.3.133).  The field is a PERCENT, exactly as its
+	// name says, and storing it 1:1 made the brownout test
+	// `measured <= minVoltage * rated` unconditionally true -- so every
+	// PowerWatcher in the mech reported a permanent brownout on a bus
+	// sitting at full rated voltage.
 	//
-	minVoltage = subsystem_resource->minVoltagePercent;
+	// The authored data leaves no other reading: bhk1 gives the Gyroscope
+	// and HUD 50 and the Searchlight 10 -- round percents, absurd as raw
+	// fractions (5000% / 1000%) -- against a bus measuring 10000 of 10000
+	// rated.  At 50% the gyro complains below 5000V, which is a sane
+	// undervoltage trip.
+	//
+	minVoltage = subsystem_resource->minVoltagePercent / 100.0f;
 		//
 	// Install the per-frame watchdog on the master instance.
 	//
@@ -889,14 +898,32 @@ void
 
 	Generator
 		*source = (Generator *)watched->ResolveVoltageSource();
-	if (
+	Logical brownout =
 		level == PoweredSubsystem::Ready &&
 		source != NULL &&
-		source->MeasuredVoltage() <= minVoltage * source->RatedVoltageOf()
-	)
+		source->MeasuredVoltage() <= minVoltage * source->RatedVoltageOf();
+	if (brownout)
 	{
 		watchdogAlarm.SetLevel(1);				// the brownout
 	}
+
+	if (getenv("BT_WATCH_LOG"))
+	{
+		static int s_shown = 0;
+		if (s_shown < 24)
+		{
+			++s_shown;
+			DEBUG_STREAM << "[watchdog] '" << GetName()
+				<< "' watched='" << watched->GetName()
+				<< "' level=" << level
+				<< " minVoltage=" << minVoltage
+				<< " measured="
+				<< ((source != NULL) ? source->MeasuredVoltage() : -1.0f)
+				<< " rated="
+				<< ((source != NULL) ? source->RatedVoltageOf() : -1.0f)
+				<< " brownout=" << (int)brownout << endl << flush;
+		}
+	}
 }
 
 void