diff --git a/firmware/application/main.cpp b/firmware/application/main.cpp
index 63913048..0d2ca15c 100755
--- a/firmware/application/main.cpp
+++ b/firmware/application/main.cpp
@@ -34,7 +34,7 @@
 
 //TODO: Cap Wav viewer position
 //TODO: Adapt wav viewer position step
-//TODO: Optimize wav viewer refresh
+//TODO: Use unit_auto_scale
 //TODO: Remove make_bistream from encoders.cpp, too complex, stinks. bitstream_append should be enough.
 //TODO: Continue work on proc_afskrx_corr, see python script (it works !)
 //TODO: Super simple text file viewer
@@ -59,10 +59,7 @@ Continuous (Fox-oring)
 60s transmit, 240s space (Classic 1/5 min) 
 60s transmit, 360s space (Classic 1/7 min) 
 */
-//TODO: Use TransmitterView in TEDI/LCR, Numbers, ...
 //TODO: FreqMan: Remove and rename categories
-//TODO: Wav visualizer
-//TODO: File browser view ?
 //TODO: Mousejack ?
 //TODO: Move frequencykeypad from ui_receiver to ui_widget (used everywhere)
 //TODO: ADS-B draw trajectory + GPS coordinates + scale, and playback
diff --git a/firmware/application/string_format.cpp b/firmware/application/string_format.cpp
index 2ad90b1f..f1213d12 100644
--- a/firmware/application/string_format.cpp
+++ b/firmware/application/string_format.cpp
@@ -170,3 +170,31 @@ std::string to_string_timestamp(const rtc::RTC& value) {
 		to_string_dec_uint(value.minute(), 2, '0') +
 		to_string_dec_uint(value.second(), 2, '0');
 }
+
+std::string unit_auto_scale(double n, const uint32_t base_nano, uint32_t precision) {
+	const uint32_t powers_of_ten[5] = { 1, 10, 100, 1000, 10000 };
+	std::string string { "" };
+	uint32_t prefix_index = base_nano;
+	double integer_part;
+	double fractional_part;
+	
+	precision = std::min((uint32_t)4, precision);
+	
+	while (n > 1000) {
+		n /= 1000.0;
+		prefix_index++;
+	}
+	
+	fractional_part = modf(n, &integer_part) * powers_of_ten[precision];
+	if (fractional_part < 0)
+		fractional_part = -fractional_part;
+	
+	string = to_string_dec_int(integer_part);
+	if (precision)
+		string += '.' + to_string_dec_uint(fractional_part, precision, '0');
+	
+	if (prefix_index != 3)
+		string += unit_prefix[prefix_index];
+	
+	return string;
+}
diff --git a/firmware/application/string_format.hpp b/firmware/application/string_format.hpp
index 8af71b15..40183167 100644
--- a/firmware/application/string_format.hpp
+++ b/firmware/application/string_format.hpp
@@ -35,6 +35,8 @@ enum TimeFormat {
 	HM = 2
 };
 
+const char unit_prefix[7] { 'n', 'u', 'm', 0, 'k', 'M', 'G' };
+
 // TODO: Allow l=0 to not fill/justify? Already using this way in ui_spectrum.hpp...
 std::string to_string_bin(const uint32_t n, const uint8_t l = 0);
 std::string to_string_dec_uint(const uint32_t n, const int32_t l = 0, const char fill = 0);
@@ -47,4 +49,6 @@ std::string to_string_short_freq(const uint64_t f);
 std::string to_string_datetime(const rtc::RTC& value, const TimeFormat format = YMDHMS);
 std::string to_string_timestamp(const rtc::RTC& value);
 
+std::string unit_auto_scale(double n, const uint32_t base_nano, uint32_t precision);
+
 #endif/*__STRING_FORMAT_H__*/
diff --git a/firmware/application/ui_encoders.cpp b/firmware/application/ui_encoders.cpp
index b985d8b7..9ac1e3b5 100644
--- a/firmware/application/ui_encoders.cpp
+++ b/firmware/application/ui_encoders.cpp
@@ -128,12 +128,8 @@ void EncodersConfigView::on_show() {
 void EncodersConfigView::draw_waveform() {
 	size_t length = frame_fragments.length();
 
-	for (size_t n = 0; n < length; n++) {
-		if (frame_fragments[n] == '0')
-			waveform_buffer[n] = 0;
-		else
-			waveform_buffer[n] = 1;
-	}
+	for (size_t n = 0; n < length; n++)
+		waveform_buffer[n] = (frame_fragments[n] == '0') ? 0 : 1;
 	
 	waveform.set_length(length);
 	waveform.set_dirty();
diff --git a/firmware/application/ui_encoders.hpp b/firmware/application/ui_encoders.hpp
index 4684db35..43165220 100644
--- a/firmware/application/ui_encoders.hpp
+++ b/firmware/application/ui_encoders.hpp
@@ -55,7 +55,7 @@ private:
 	//uint8_t scan_count;
 	//double scan_progress;
 	//unsigned int scan_index;
-	int8_t waveform_buffer[512];
+	int16_t waveform_buffer[512];
 	const encoder_def_t * encoder_def { };
 	//uint8_t enc_type = 0;
 
diff --git a/firmware/application/ui_view_wav.cpp b/firmware/application/ui_view_wav.cpp
index 4719053e..8e403c0e 100644
--- a/firmware/application/ui_view_wav.cpp
+++ b/firmware/application/ui_view_wav.cpp
@@ -32,29 +32,34 @@ namespace ui {
 void ViewWavView::update_scale(int32_t new_scale) {
 	scale = new_scale;
 	ns_per_pixel = (1000000000UL / wav_reader->sample_rate()) * scale;
-	field_pos_samples.set_step(scale);
 	refresh_waveform();
+	refresh_measurements();
 }
 
 void ViewWavView::refresh_waveform() {
-	int16_t sample;
-	
 	for (size_t i = 0; i < 240; i++) {
 		wav_reader->data_seek(position + (i * scale));
-		wav_reader->read(&sample, 2);
-		
-		waveform_buffer[i] = sample >> 8;
+		wav_reader->read(&waveform_buffer[i], sizeof(int16_t));
 	}
 	
+	waveform.set_dirty();
+	
+	// Window
+	uint64_t w_start = (position * 240) / wav_reader->sample_count();
+	uint64_t w_width = (scale * 240) / (wav_reader->sample_count() / 240);
+	display.fill_rectangle({ 0, 10 * 16 + 1, 240, 16 }, Color::black());
+	display.fill_rectangle({ (Coord)w_start, 21 * 8, (Dim)w_width + 1, 8 }, Color::white());
+	display.draw_line({ 0, 10 * 16 + 1 }, { (Coord)w_start, 21 * 8 }, Color::white());
+	display.draw_line({ 239, 10 * 16 + 1 }, { (Coord)(w_start + w_width), 21 * 8 }, Color::white());
+}
+
+void ViewWavView::refresh_measurements() {
 	uint64_t span_ns = ns_per_pixel * abs(field_cursor_b.value() - field_cursor_a.value());
+	
 	if (span_ns)
-		text_delta.set(to_string_dec_uint(span_ns / 1000) + "us (" + to_string_dec_uint(1000000000UL / span_ns) + "Hz)");
+		text_delta.set(unit_auto_scale(span_ns, 0, 3) + "s (" + to_string_dec_uint(1000000000UL / span_ns) + "Hz)");
 	else
 		text_delta.set("0us ?Hz");
-	
-	//waveform.set_dirty();
-	
-	set_dirty();
 }
 
 void ViewWavView::paint(Painter& painter) {
@@ -62,22 +67,9 @@ void ViewWavView::paint(Painter& painter) {
 	painter.draw_hline({ 0, 6 * 16 - 1 }, 240, Color::grey());
 	painter.draw_hline({ 0, 10 * 16 }, 240, Color::grey());
 	
-	// 0~127 to 0~15 color index
+	// Overall amplitude view, 0~127 to 0~255 color index
 	for (size_t i = 0; i < 240; i++)
-		painter.draw_vline({ (Coord)i, 11 * 16 }, 8, amplitude_colors[amplitude_buffer[i] >> 3]);
-	
-	// Window
-	uint64_t w_start = (position * 240) / wav_reader->sample_count();
-	uint64_t w_width = (scale * 240) / (wav_reader->sample_count() / 240);
-	painter.fill_rectangle({ 0, 10 * 16 + 1, 240, 16 }, Color::black());
-	painter.fill_rectangle({ (Coord)w_start, 21 * 8, (Dim)w_width + 1, 8 }, Color::white());
-	display.draw_line({ 0, 10 * 16 + 1 }, { (Coord)w_start, 21 * 8 }, Color::white());
-	display.draw_line({ 239, 10 * 16 + 1 }, { (Coord)(w_start + w_width), 21 * 8 }, Color::white());
-	
-	// Cursors
-	painter.fill_rectangle({ 0, 6 * 16 - 8, 240, 7 }, Color::black());
-	painter.draw_vline({ (Coord)field_cursor_a.value(), 11 * 8 }, 7, Color::cyan());
-	painter.draw_vline({ (Coord)field_cursor_b.value(), 11 * 8 }, 7, Color::magenta());
+		painter.draw_vline({ (Coord)i, 11 * 16 }, 8, spectrum_rgb2_lut[amplitude_buffer[i] << 1]);
 }
 
 void ViewWavView::on_pos_changed() {
@@ -101,7 +93,7 @@ void ViewWavView::load_wav(std::filesystem::path file_path) {
 	
 	text_filename.set(file_path.filename().string());
 	auto ms_duration = wav_reader->ms_duration();
-	text_duration.set(to_string_dec_uint(ms_duration / 1000) + "s" + to_string_dec_uint(ms_duration % 1000) + "ms");
+	text_duration.set(unit_auto_scale(ms_duration, 2, 3) + "s");
 	
 	wav_reader->rewind();
 	
@@ -117,13 +109,7 @@ void ViewWavView::load_wav(std::filesystem::path file_path) {
 		for (size_t s = 0; s < subsampling_factor; s++) {
 			wav_reader->data_seek(((i * subsampling_factor) + s) * skip);
 			wav_reader->read(&sample, 2);
-			
-			if (sample < 0)
-				sample = -sample;
-			
-			sample >>= 8;
-			
-			average += sample;
+			average += (abs(sample) >> 8);
 		}
 		
 		amplitude_buffer[i] = average / subsampling_factor;
@@ -135,18 +121,10 @@ void ViewWavView::load_wav(std::filesystem::path file_path) {
 
 void ViewWavView::reset_controls() {
 	field_scale.set_value(1);
-	field_scale.on_change = [this](int32_t value) {
-		update_scale(value);
-	};
-	
 	field_pos_seconds.set_value(0);
-	field_pos_seconds.on_change = [this](int32_t) {
-		on_pos_changed();
-	};
 	field_pos_samples.set_value(0);
-	field_pos_samples.on_change = [this](int32_t) {
-		on_pos_changed();
-	};
+	field_cursor_a.set_value(0);
+	field_cursor_b.set_value(0);
 }
 	
 ViewWavView::ViewWavView(
@@ -175,19 +153,30 @@ ViewWavView::ViewWavView(
 		auto open_view = nav.push<FileLoadView>();
 		open_view->on_changed = [this](std::filesystem::path file_path) {
 			load_wav(file_path);
+			field_pos_seconds.focus();
 		};
 	};
 	
-	reset_controls();
+	field_scale.on_change = [this](int32_t value) {
+		update_scale(value);
+	};
+	field_pos_seconds.on_change = [this](int32_t) {
+		on_pos_changed();
+	};
+	field_pos_samples.on_change = [this](int32_t) {
+		on_pos_changed();
+	};
 	
-	field_cursor_a.set_value(0);
-	field_cursor_a.on_change = [this](int32_t) {
-		refresh_waveform();
+	field_cursor_a.on_change = [this](int32_t v) {
+		waveform.set_cursor(0, v);
+		refresh_measurements();
 	};
-	field_cursor_b.set_value(0);
-	field_cursor_b.on_change = [this](int32_t) {
-		refresh_waveform();
+	field_cursor_b.on_change = [this](int32_t v) {
+		waveform.set_cursor(1, v);
+		refresh_measurements();
 	};
+	
+	reset_controls();
 }
 
 void ViewWavView::focus() {
diff --git a/firmware/application/ui_view_wav.hpp b/firmware/application/ui_view_wav.hpp
index bd9c5525..3a67ed2f 100644
--- a/firmware/application/ui_view_wav.hpp
+++ b/firmware/application/ui_view_wav.hpp
@@ -23,6 +23,7 @@
 #include "ui.hpp"
 #include "ui_navigation.hpp"
 #include "io_wave.hpp"
+#include "spectrum_color_lut.hpp"
 
 namespace ui {
 
@@ -41,32 +42,14 @@ private:
 	
 	void update_scale(int32_t new_scale);
 	void refresh_waveform();
+	void refresh_measurements();
 	void on_pos_changed();
 	void load_wav(std::filesystem::path file_path);
 	void reset_controls();
-	
-	const Color amplitude_colors[16] = {
-		{ 0x00, 0x3F, 0xB0 },
-		{ 0x00, 0x6D, 0xB5 },
-		{ 0x00, 0x9C, 0xBA },
-		{ 0x00, 0xBF, 0xB0 },
-		{ 0x00, 0xC5, 0x86 },
-		{ 0x00, 0xCA, 0x5A },
-		{ 0x00, 0xCF, 0x2A },
-		{ 0x06, 0xD4, 0x00 },
-		{ 0x3A, 0xDA, 0x00 },
-		{ 0x71, 0xDF, 0x00 },
-		{ 0xAA, 0xE4, 0x00 },
-		{ 0xE6, 0xE9, 0x00 },
-		{ 0xEF, 0xB9, 0x00 },
-		{ 0xF4, 0x83, 0x00 },
-		{ 0xF9, 0x4B, 0x00 },
-		{ 0xFF, 0x0F, 0x00 }
-	};
 
 	std::unique_ptr<WAVFileReader> wav_reader { };
 	
-	int8_t waveform_buffer[240] { };
+	int16_t waveform_buffer[240] { };
 	uint8_t amplitude_buffer[240] { };
 	int32_t scale { 1 };
 	uint64_t ns_per_pixel { };