diff --git a/Bandscope.ino b/Bandscope.ino
index 32469c1..76c4988 100644
--- a/Bandscope.ino
+++ b/Bandscope.ino
@@ -1,4 +1,6 @@
 
+uint32_t	colourTest;
+
 /*
  * Initialise variables and SI4432 for the low frequency sweep
  */
@@ -39,12 +41,16 @@ void initBandscope()
 
 /*
  *  The "tSprite" is used for displaying the data above the scan grid - we don't use it in this mode
- *  The "sSprite" is for displaying the sidebar stuff, no sidebar in this mode
+ *  The "sSprite" is for displaying the sidebar stuff, but reused here for the waterfall
  */
 
 	tSprite.deleteSprite();
 
 	sSprite.deleteSprite();
+	sSprite.setColorDepth (16);							// we don't need 16bit but its faster
+	sSprite.setAttribute ( PSRAM_ENABLE, false );		// Don't use the PSRAM on the WROVERs
+	sSprite.createSprite ( gridWidth, waterfallHeight );    // Full width
+	sSprite.setScrollRect(0, 0, gridWidth, waterfallHeight, TFT_BLACK);
 /*
  *  Create and draw the sprite for the gain scale
  */
@@ -113,7 +119,7 @@ static uint32_t		peakFreq;
 static uint16_t		peakIndex;
 static uint16_t		pointsPastPeak;
 static uint16_t		pointsPastDip;
-static uint16_t		minRSSI;			// Minimum level for the sweep
+static uint16_t		minRSSI = 255;			// Minimum level for the sweep
 static uint16_t		lastMinRSSI;		// Minimum level for the previous sweep
 
 static bool			resetAverage;		// Flag to indicate a setting has changed and average valuesneeds to be reset
@@ -140,7 +146,6 @@ static uint16_t		chunkIndex;
 	{
 	 	if ( initSweep || changedSetting )		//  Something has changed, or a first start, so need to owrk out some basic things
 	 	{
-//			Serial.println("InitBandscope or changedSetting");
 			sweepPoints = setting.BandscopePoints;
 			autoSweepFreqStep = ( setting.BandscopeSpan ) / sweepPoints;
 	 		
@@ -227,9 +232,10 @@ static uint16_t		chunkIndex;
 			SetPowerLevel ( actualPower );
 			setActualPowerRequested = false; 
 
-//			Serial.printf ( "Setting actual Power %f \n", actualPower );
 		}
 
+		lastMinRSSI = minRSSI;
+		minRSSI = 255;						// real value should always be less
 
 		DisplayBandscopeInfo ();			// Display axis and other info
 
@@ -265,14 +271,11 @@ static uint16_t		chunkIndex;
 		if ( ( nowMicros - setFreqMicros + delaytime > 200 ) &&
 			( (nowMicros - lastWebsocketMicros > websocketInterval) || (numberOfWebsocketClients > 0) ) )
 		{
-//			Serial.print("W");
-	    	webSocket.loop ();					// Check websockets - includes Yield() to allow other events to run
-//			Serial.println("w");
+	    	webSocket.loop ();					// Check websockets - includes Yield() to allow other tasks to run
 			lastWebsocketMicros = nowMicros;
 		}
 		if ( nowMicros - setFreqMicros > 100 )		// Wait some time to allow DMA sprite write to finish!
 				UiProcessTouch ();						// Check the touch screen
-//		Serial.println("w");
 		nowMicros = micros();
 	}
 
@@ -363,6 +366,9 @@ static uint16_t		chunkIndex;
 
 #endif											// #ifdef USE_WIFI
 
+	if (rxRSSI < minRSSI)						// Detect minimum for sweep
+		minRSSI = rxRSSI;
+
 
 	uint16_t pixelsPerPoint = SCREEN_WIDTH / displayPoints;
 	for (uint16_t i = 0; i< pixelsPerPoint; i++) {
@@ -425,6 +431,18 @@ static uint16_t		chunkIndex;
 	
 		if ( tmp > 0 )				// Only push if not first point (two pixel wide img)
 			img.pushSprite ( xOrigin+tmp, yOrigin );
+
+		// put data into the top row of the waterfall
+		// 16 bit colours have 5 bits for Red, 6 bits for Green, 5 bits for Blue
+		// We will just change the green here for first test
+
+		uint32_t pixelColour = (rxRSSI - 17) << 5 ;		// testing colours
+		if (rxRSSI < 17)
+			pixelColour = 0;
+		if (colourTest > 0)
+			pixelColour = colourTest;
+//		Serial.printf("rxRSSI %i; colour %i \n", rxRSSI, pixelColour);
+		sSprite.drawPixel ( tmp, 0, pixelColour );
 		
 	}
 
@@ -466,6 +484,10 @@ static uint16_t		chunkIndex;
 		}
 #endif							// #ifdef USE_WIFI   
 
+		// scroll the waterfall down one pixel
+		sSprite.scroll( 0, 1 );
+		sSprite.pushSprite( 0, gridHeight + 1 );
+
 	}							// End of "if ( autoSweepStep >= sweepPoints )"
 	
 }								// End of "doBandscope"
diff --git a/cmd.cpp b/cmd.cpp
index 61e0000..fb03400 100644
--- a/cmd.cpp
+++ b/cmd.cpp
@@ -97,6 +97,7 @@ extern	uint8_t		showRSSI;			// When true, RSSI readings are displayed
 extern	int 		initSweep;			// Set by the "RSSI" command to restart the sweep
 extern	bool		paused;
 
+extern	uint32_t	colourTest;
 
 extern	Marker marker[MARKER_COUNT];	// Array of marker objects
 
@@ -167,6 +168,7 @@ extern	void 	setMode (uint16_t newMode);
 		{ "TGLODRIVE",	  MSG_TG_LO_DRIVE },	// Set Track Generator LO Drive level
 		{ "IFSIGNAL",	  MSG_IFSIGNAL	},	// IF sweep signal frequency
 		{ "TGOFFSET",	  MSG_TGOFFSET	},	// Offset TG IF from SA IF to reduce pass through
+		{ "CTEST",	  	  MSG_COLOURTEST	},	// Work out how colours work!
 		{ "",			  MSG_NONE      }	// Unrecognized	command
 	};
 
@@ -1574,6 +1576,25 @@ uint8_t		reg69;							// Ditto
 				return false;
 			}
 
+
+		case MSG_COLOURTEST:
+			if ( dataLen != 0 )							// Anything entered?
+			{
+				tempValue = atoi ( dataBuff );			// Yes, get new value
+				if ( ( tempValue >= 0 ) && (tempValue <= 65535) )
+				{
+					colourTest = tempValue;
+					return true;
+				}
+				else												// Nothing specified
+				{
+					Serial.println ( "Invalid Colour" );
+					return false;
+				}
+			}
+
+			
+
 		default:
 			return false;
 	}											// End of "switch"
diff --git a/cmd.h b/cmd.h
index 440b088..4d33289 100644
--- a/cmd.h
+++ b/cmd.h
@@ -72,7 +72,7 @@
 #define MSG_TGOFFSET    43		// Offset TG IF frequency from SA IF
 #define MSG_BANDSCOPE   44		// Set Bandscope Mode
 #define MSG_IFSWEEP     45		// Set IF Sweep Mode
-
+#define MSG_COLOURTEST  46		// test of colours - remove this when done!
 
 typedef struct					// Keeps everything together
 {
diff --git a/simpleSA.ino b/simpleSA.ino
index f7a43cf..cd8bcd7 100644
--- a/simpleSA.ino
+++ b/simpleSA.ino
@@ -2,6 +2,7 @@
  *	"simpleSA.ino"
  *
  *	This is the main program file for the "TinySA for ESP32" (spectrum analyzer) 
+ *	
  *
  *   Copyright (C) 2020  David Wilde (M0WID), John Price (WA2FZW)
  *
@@ -22,17 +23,21 @@
  *	The starting point for this version is the "tinySA_touch05" software developed
  *	by David (M0WID). 
  *	That software was based on the original version for STM "Blue Pill" by Erik Kaashoek PD0EK.
+ *	For more information on that version visit https://groups.io/g/HBTE/topics
+ *	
+ *	Glen VK3PE has designed a set of PCB - see http://www.carnut.info/tinySA/tinySA.html
+ *	
+ *	Erik has since gone on to produce a commecial version, google tinySA, and this software 
+ *	has been renamed simpleSA to avoid confusion.
  *
  *	Modified by John Price (WA2FZW):
  *
  *		Version 1.0:
- *
  *			Just add comments, try to figure out how it all works and move some stuff
  *			around for clarity!
  *
  *
  *		Version 1.1:
- *
  *			Added the file "Si4432.h" which contains symbols for all the Si4432
  *			registers and some other things related to it's operation.
  *
@@ -54,12 +59,10 @@
  *
  *
  *		Version 1.6:
- *
  *			Added the file "Si4432.cpp" and moved all of the functions to handle the
  *			interface to the hardware out of here. *
  *
  *		Version 1.7:
- *
  *			Moved all the global variables to the top of the file and moved the "setup"
  *			and "loop" functions to the top where they are customarily found.
  *
@@ -69,18 +72,15 @@
  *
  *
  *		Version 1.8:
- *
  *			Replaced the original code to handle the Si4432 modules with a class/object
  *			implementation using real SPI protocol.
  *
  *
  *		Version 2.0:
- *
  *			Overhauled the serial command handler and help menu.
  *
  *
  *		Version 2.1:
- *
  *			A major overhaul of the entire architecture! I moved all the functions that
  *			handle reading and processing commands from the serial input into "Cmd.cpp".
  *			This is the first step into being able to use common command processing for
@@ -88,14 +88,12 @@
  *
  *
  *		Version 2.7:
- *
  *			More restructuring. Added markers . Added more
  *			commands to the serial command handler. Re-organized the touch screen menus
  *			in a more logical hierarchy and added some new capabilities there.
  *
  *
  *		Version 2.8 Changes by M0WID:
- *
  *			Data now pushed to the web clients
  *			Grid y changed to have 10 divisions
  *			Various bug fixes