diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 150f491..af33140 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -87,7 +87,8 @@ include_directories(
 	external 
 	scan 
 	server 
-	sigproc 
+	sigproc
+	util 
 	external/PiScan-protobuf 
 	external/loguru
 	external/tinyxml
diff --git a/src/core/PiScan.h b/src/core/PiScan.h
index 7adb21d..44f1a2c 100644
--- a/src/core/PiScan.h
+++ b/src/core/PiScan.h
@@ -29,10 +29,11 @@ ScannerContext getScannerContext();
 void setTunerGain(float gain);
 void setDemodSquelch(float level);
 DemodContext getDemodContext();
-void audioMute(bool mute = true);
+void squelchBreak(bool mute = true);
 long long getTunerSampleRate();
 
 /* server functions */
 void scannerContextUpdate(ScannerContext ctx);
 void demodContextUpdate(DemodContext ctx);
+void signalLevelUpdate(int level);
 }
diff --git a/src/core/ScannerSM.cpp b/src/core/ScannerSM.cpp
index 0b3f92f..097819e 100644
--- a/src/core/ScannerSM.cpp
+++ b/src/core/ScannerSM.cpp
@@ -170,7 +170,7 @@ void ScannerSM::ST_Hold(EventData* data){
 	if(currentState != lastState || indexHold)
 		_broadcastContextUpdate();
 
-	DLOG_F(6, "Ext hold: %i", _externalHold.load());
+	DLOG_F(8, "Ext hold: %i", _externalHold.load());
 
 	/* start receive if signal active */
 	if (_currentEntry->hasSignal()) {
@@ -320,7 +320,7 @@ void ScannerSM::_broadcastContextUpdate() {
 }
 
 void ScannerSM::_enableAudioOut(bool en){
-	app::audioMute(en);
+	app::squelchBreak(en);
 }
 
 void ScannerSM::giveMessage(shared_ptr<Message> message) {
diff --git a/src/core/messages.h b/src/core/messages.h
index 1c9c41a..2e2c553 100644
--- a/src/core/messages.h
+++ b/src/core/messages.h
@@ -114,6 +114,7 @@ struct ServerMessage : public Message {
 	~ServerMessage() {};
 	enum {
 		CONTEXT_UPDATE,
+		SIGNAL_LEVEL,
 
 		NOTIFY_ALL_CLIENTS,
 		NOTIFY_USERS,
diff --git a/src/piScan_backend.cpp b/src/piScan_backend.cpp
index 6c5fc6c..bc333af 100644
--- a/src/piScan_backend.cpp
+++ b/src/piScan_backend.cpp
@@ -371,8 +371,8 @@ DemodContext app::getDemodContext(){
 	return DemodContext(demod.getTunerGain(), demod.getSquelch());
 }
 
-void app::audioMute(bool mute){
-	demod.audioMute(mute);
+void app::squelchBreak(bool mute){
+	demod.squelchBreak(mute);
 }
 
 long long app::getTunerSampleRate() {
@@ -397,6 +397,10 @@ void app::demodContextUpdate(DemodContext ctx){
 	connectionManager.giveMessage(make_shared<ServerMessage>(DEMOD, ServerMessage::CONTEXT_UPDATE, new DemodContext(ctx)));
 }
 
+void app::signalLevelUpdate(int level){
+	connectionManager.giveMessage(make_shared<ServerMessage>(DEMOD, ServerMessage::SIGNAL_LEVEL, new int(level)));
+}
+
 }
 
 using namespace piscan;
diff --git a/src/server/DebugServer.cpp b/src/server/DebugServer.cpp
index 12a6e81..438b82f 100644
--- a/src/server/DebugServer.cpp
+++ b/src/server/DebugServer.cpp
@@ -201,6 +201,10 @@ void DebugConsole::handleSystemInfo(const SystemInfo info){
 	}
 }
 
+void DebugConsole::handleSignalLevel(const int level){
+	std::cerr << "\r" << "Signal: " << level << "\t\t\t\t";
+}
+
 void DebugServer::start(){
 	//this->_connection(new DebugConsole());
 	this->_host.requestConnection(_connection);
diff --git a/src/server/DebugServer.h b/src/server/DebugServer.h
index 7fb0246..3a30058 100644
--- a/src/server/DebugServer.h
+++ b/src/server/DebugServer.h
@@ -32,6 +32,7 @@ public:
 	void contextUpdate(const DemodContext context);
 	void handleSystemMessage(const GeneralMessage message);
 	void handleSystemInfo(const SystemInfo info);
+	void handleSignalLevel(const int level);
 
 	const std::string identifier() {
 		return "Debug Console";
diff --git a/src/server/ServerManager.cpp b/src/server/ServerManager.cpp
index 3102751..9dfc34e 100644
--- a/src/server/ServerManager.cpp
+++ b/src/server/ServerManager.cpp
@@ -225,6 +225,7 @@ int ServerManager::giveRequest(void* request){
 void ServerManager::_handleMessage(std::shared_ptr<Message> message){
 	assert(message->destination == SERVER_MAN);
 	auto msg = std::dynamic_pointer_cast<ServerMessage>(message);
+	int* level = nullptr;
 	switch (msg->type) {
 	case ServerMessage::CONTEXT_UPDATE:
 		switch(message->source){
@@ -247,6 +248,12 @@ void ServerManager::_handleMessage(std::shared_ptr<Message> message){
 		disconnectClients();
 		_run = false;
 		break;
+	case ServerMessage::SIGNAL_LEVEL:
+		DLOG_F(7, "Broadcast siglevel update");
+		level = reinterpret_cast<int*>(msg->pData);
+		_broadcastSignalLevelUpdate(*level);
+		delete level;
+		break;
 	default:
 		break;
 	}
@@ -327,3 +334,12 @@ std::shared_ptr<Message> ServerManager::_makeContextRequest(ClientRequest* rq){
 	}
 }
 
+void ServerManager::_broadcastSignalLevelUpdate(int level) {
+	for (size_t i = 0; i < MAX_CONNECTIONS; i++) {
+		if (_connections[i] != nullptr) {
+			Connection* con = _connections[i].get();
+			con->handleSignalLevel(level);
+		}
+	}
+}
+
diff --git a/src/server/ServerManager.h b/src/server/ServerManager.h
index c5811ce..6088c28 100644
--- a/src/server/ServerManager.h
+++ b/src/server/ServerManager.h
@@ -76,6 +76,8 @@ private:
 	void _broadcastGeneralMessage(unsigned char group, GeneralMessage& message);
 	std::shared_ptr<Message> _makeContextRequest(ClientRequest* rq);
 
+	void _broadcastSignalLevelUpdate(int level);
+
 };
 }
 #endif /* SERVER_SERVERMANAGER_H_ */
diff --git a/src/server/SocketServer.cpp b/src/server/SocketServer.cpp
index 124ed6a..e864ba0 100644
--- a/src/server/SocketServer.cpp
+++ b/src/server/SocketServer.cpp
@@ -134,6 +134,11 @@ void SocketConnection::handleSystemInfo(const SystemInfo info){
 	delete ctx;
 }
 
+void SocketConnection::handleSignalLevel(const int level){
+	//TODO
+	(void) level;
+}
+
 void SocketConnection::_startRead() {
 	_socket.async_read_some(boost::asio::buffer(_readBuffer, READ_BUFFER_LENGTH),
 			boost::bind(&SocketConnection::_handleRead, shared_from_this(),
diff --git a/src/server/SocketServer.h b/src/server/SocketServer.h
index e869e76..32e9ec5 100644
--- a/src/server/SocketServer.h
+++ b/src/server/SocketServer.h
@@ -41,6 +41,7 @@ public:
 	void contextUpdate(const DemodContext context);
 	void handleSystemMessage(const GeneralMessage message);
 	void handleSystemInfo(const SystemInfo info);
+	void handleSignalLevel(const int level);
 
 	tcp::socket& socket() { return _socket; };
 
diff --git a/src/server/connection.h b/src/server/connection.h
index 0bcd2b4..4ec06a1 100644
--- a/src/server/connection.h
+++ b/src/server/connection.h
@@ -58,6 +58,7 @@ public:
 	virtual void contextUpdate(const DemodContext context) = 0;
 	virtual void handleSystemMessage(const GeneralMessage message) = 0;
 	virtual void handleSystemInfo(const SystemInfo info) = 0;
+	virtual void handleSignalLevel(const int level) = 0;
 
 	virtual const std::string identifier() = 0;
 
diff --git a/src/sigproc/Demodulator.cpp b/src/sigproc/Demodulator.cpp
index b264c89..5ca51ba 100644
--- a/src/sigproc/Demodulator.cpp
+++ b/src/sigproc/Demodulator.cpp
@@ -6,6 +6,7 @@
  */
 
 #include <unistd.h>
+#include <functional>
 
 #include "PiScan.h"
 #include "Demodulator.h"
@@ -14,6 +15,7 @@
 #define DEFAULT_SDR_SAMPLE_RATE	2048000
 #define INIT_FREQUENCY			100000000
 #define NUM_RATES_DEFAULT	4
+#define SIGLEVEL_REFRESH_INTERVAL	250 // milliseconds
 
 using namespace piscan;
 
@@ -145,6 +147,14 @@ void Demodulator::start(){
 	//setModem(NFM);
 	_demodMgr.setActiveDemodulator(_demods[NFM], false);
 
+	//create signal level refresh timer
+	std::function<void()> func([this](){
+		int level = getSignalStrength();
+		LOG_F(7, "Signal strength %i", level);
+		app::signalLevelUpdate(level);
+	});
+	_sigLevelRefresher.create(SIGLEVEL_REFRESH_INTERVAL, func);
+
 	//auto message = std::make_shared<ControllerMessage>(DEMOD, ControllerMessage::NOTIFY_READY);
 	//_centralQueue.giveMessage(message);
 	LOG_F(1, "Demodulator started");
@@ -334,7 +344,10 @@ float Demodulator::getSquelch(){
 	return _squelchLevel;
 }
 
-void Demodulator::audioMute(bool mute){
+void Demodulator::squelchBreak(bool mute){
+	//mute = !mute;
+	mute ? _sigLevelRefresher.start() : _sigLevelRefresher.stop();
+
 	_demodMgr.getCurrentModem()->setMuted(!mute);
 }
 
diff --git a/src/sigproc/Demodulator.h b/src/sigproc/Demodulator.h
index d37493b..d05e9ab 100644
--- a/src/sigproc/Demodulator.h
+++ b/src/sigproc/Demodulator.h
@@ -16,6 +16,7 @@
 #include "SDRDeviceInfo.h"
 #include "Configuration.h"
 #include "synchronize.h"
+#include "IntervalTimer.h"
 
 
 namespace piscan {
@@ -65,7 +66,7 @@ public:
 	void setTunerGain(float gain);
 	float getTunerGain();
 	float getSquelch();
-	void audioMute(bool mute);
+	void squelchBreak(bool mute);
 	long long getTunerSampleRate();
 
 private:
@@ -80,7 +81,7 @@ private:
 
 	std::map<Modulation, DemodulatorInstancePtr> _demods;
 
-	
+	IntervalTimer _sigLevelRefresher;
 
 	void _handleMessage(std::shared_ptr<DemodMessage> message);
 	void _handleRequest(ClientRequest& request);
diff --git a/src/tests/CMakeLists.txt b/src/tests/CMakeLists.txt
index 8c49db4..d635a15 100644
--- a/src/tests/CMakeLists.txt
+++ b/src/tests/CMakeLists.txt
@@ -2,6 +2,7 @@ project(piScan_backend_tests)
 
 add_executable(piScan_backend_tests EXCLUDE_FROM_ALL test_ScannerStateMachine.cpp)
 add_executable(testclient EXCLUDE_FROM_ALL testclient.cpp)
+add_executable(test_utils EXCLUDE_FROM_ALL test_utils.cpp)
 
 option(DETACH_KERNEL_DRIVER "Detach kernel driver if loaded" OFF)
 if (DETACH_KERNEL_DRIVER)
@@ -12,3 +13,4 @@ else (DETACH_KERNEL_DRIVER)
 endif (DETACH_KERNEL_DRIVER)
 
 target_link_libraries(testclient server external pthread boost_system protobuf dl)
+target_link_libraries(test_utils pthread)
diff --git a/src/tests/test_utils.cpp b/src/tests/test_utils.cpp
new file mode 100644
index 0000000..84dc675
--- /dev/null
+++ b/src/tests/test_utils.cpp
@@ -0,0 +1,76 @@
+/*
+ * test_utils.cpp
+ *
+ *  Created on: Feb 12, 2020
+ *      Author: ezra
+ */
+
+#include <iostream>
+#include <functional>
+#include <chrono>
+
+#include "IntervalTimer.h"
+
+using piscan::IntervalTimer;
+using std::cout;
+using std::chrono::milliseconds;
+
+int main(int argc, char** argv){
+	(void) argc;
+	(void) argv;
+
+	cout << "testing IntervalTimer" << std::endl;
+	size_t runCount = 0;
+	auto func = std::function<void(void)>([&runCount](){
+		runCount++;
+		cout << "\ttimer running\n";
+	});
+
+	IntervalTimer it;
+	cout << "create 10ms timer\n";
+	it.create(10, func);
+	cout << "start timer\n";
+	it.start();
+	cout << "waiting 50ms\n";
+	std::this_thread::sleep_for(milliseconds(50));
+	cout << "stopping timer\n";
+	it.stop();
+	cout << "timer executed " << runCount << " times\n";
+
+	IntervalTimer& it2 = *(new IntervalTimer());
+	cout << "recreating timer, 15ms\n";
+	runCount = 0;
+	it2.create(15, func);
+	cout << "waiting 50ms before starting\n";
+	std::this_thread::sleep_for(milliseconds(50));
+	cout << "start timer\n";
+	it2.start();
+	cout << "waiting 50ms\n";
+	std::this_thread::sleep_for(milliseconds(50));
+	cout << "destroy while timer is running\n";
+	delete &it2;
+	cout << "timer destroyed\n";
+
+	IntervalTimer it3;
+	cout << "recreating timer, 20ms\n";
+	runCount = 0;
+	it3.create(20, func);
+	cout << "start timer, 2 runs\n";
+	it3.start();
+	cout << "wait 50ms\n";
+	std::this_thread::sleep_for(milliseconds(50));
+	cout << "stop timer\n";
+	it3.stop();
+	cout << "ran " << runCount << " times. wait 50ms\n";
+	std::this_thread::sleep_for(milliseconds(50));
+	cout << "restart timer\n";
+	it3.start();
+	cout << "wait 50ms\n";
+	std::this_thread::sleep_for(milliseconds(50));
+	cout << "stop timer\n";
+	it3.stop();
+	cout << "total " << runCount << " runs\n";
+
+	return 0;
+}
+
diff --git a/src/util/CMakeLists.txt b/src/util/CMakeLists.txt
new file mode 100644
index 0000000..e69de29
diff --git a/src/util/IntervalTimer.h b/src/util/IntervalTimer.h
new file mode 100644
index 0000000..e377ff8
--- /dev/null
+++ b/src/util/IntervalTimer.h
@@ -0,0 +1,133 @@
+/*
+ * IntervalTimer.h
+ *
+ *  Created on: Feb 12, 2020
+ *      Author: ezra
+ */
+
+#pragma once
+
+#include <atomic>
+#include <chrono>
+#include <condition_variable>
+#include <functional>
+#include <mutex>
+#include <thread>
+
+#include <iostream>
+
+namespace piscan {
+
+using std::thread;
+using std::mutex;
+using std::condition_variable;
+using std::atomic_bool;
+using std::function;
+using std::unique_lock;
+using std::chrono::milliseconds;
+using std::chrono::high_resolution_clock;
+using std::chrono::duration_cast;
+
+class IntervalTimer {
+public:
+	IntervalTimer(): _runTimer(false), _execute(false) {};
+	~IntervalTimer(){
+		if(_execute.load())
+			destroy();
+	};
+
+	inline void create(long long interval, function<void()> func){
+		_execute = true;
+		_runTimer = false;
+		_ready = false;
+
+		_timerThread = thread([this, interval, func](){
+			while(_execute){
+				{
+					unique_lock<std::mutex> lock(_mtx);
+					while(!_runTimer.load() && _execute.load()){
+						_cv.wait(lock);
+					}
+					lock.unlock();
+
+					if(!_execute.load()) break;
+				}
+
+				auto periodStart = high_resolution_clock::now();
+
+				func();
+
+				{
+					milliseconds remainingSleep(interval);
+					bool sleep = true;
+
+					unique_lock<std::mutex> lock(_sleepMtx);
+
+					while(sleep){
+						if(_sleepTime.wait_for(lock, remainingSleep, [this]{ return _stateChanged.load();})){
+							//std::cout << "\t\ttimer state changed\n";
+							_stateChanged = false;
+							break;
+						}
+						// should account for spurious wakeup
+						else{
+							//std::cout << "\t\tstate change false\n";
+							auto elapsed = high_resolution_clock::now() - periodStart;
+							remainingSleep -= duration_cast<milliseconds>(elapsed);
+							//std::cout << "\t\t" << remainingSleep.count() << "\n";
+							if(remainingSleep.count() <= 0){
+								sleep = false;
+								//std::cout << "\t\ttimed out\n";
+							}
+						}
+					}
+					//std::cout << "\t\twoken up\n";
+				}
+			}
+		});
+		_timerThread.detach();
+
+	}
+
+	inline void start(){
+        unique_lock<mutex> lock(_mtx);
+        _runTimer = true;
+        _stateChanged = false;
+        _cv.notify_all();
+        //unique_lock<mutex> lock2(_sleepMtx);
+        //_sleepTime.notify_all();
+
+	}
+
+	inline void stop(){
+		//unique_lock<mutex> lock(_mtx);
+		_runTimer = false;
+		_stateChanged = true;
+		unique_lock<mutex> lock2(_sleepMtx);
+		_sleepTime.notify_all();
+	}
+
+private:
+	inline void destroy(){
+		//std::cout << "\tdestroy timer\n";
+		_execute = false;
+		unique_lock<mutex> lock(_mtx);
+		_cv.notify_all();
+		stop();
+	}
+
+private:
+	thread _timerThread;
+	atomic_bool _runTimer;
+	atomic_bool _execute;
+	atomic_bool _stateChanged{false};
+
+	mutex _mtx;
+	condition_variable _cv;
+	mutex _sleepMtx;
+	condition_variable _sleepTime;
+	bool _ready = false;
+};
+
+} /* namespace piscan */
+
diff --git a/src/core/synchronize.h b/src/util/synchronize.h
similarity index 100%
rename from src/core/synchronize.h
rename to src/util/synchronize.h
diff --git a/src/core/threadname.h b/src/util/threadname.h
similarity index 100%
rename from src/core/threadname.h
rename to src/util/threadname.h