diff --git a/include/cyclic.h b/include/cyclic.h
index e263a678..1c4da4dd 100644
--- a/include/cyclic.h
+++ b/include/cyclic.h
@@ -12,5 +12,6 @@ void do_timesync(void);
 uint64_t uptime(void);
 void reset_counters(void);
 int redirect_log(const char *fmt, va_list args);
+uint32_t getFreeRAM();
 
 #endif
\ No newline at end of file
diff --git a/include/display.h b/include/display.h
index 492af565..99379b58 100644
--- a/include/display.h
+++ b/include/display.h
@@ -2,6 +2,7 @@
 #define _DISPLAY_H
 
 #include <U8x8lib.h>
+#include "cyclic.h"
 
 extern uint8_t volatile DisplayState;
 extern HAS_DISPLAY u8x8;
diff --git a/include/globals.h b/include/globals.h
index da547af3..8c429048 100644
--- a/include/globals.h
+++ b/include/globals.h
@@ -8,6 +8,7 @@
 #include <set>
 #include <array>
 #include <algorithm>
+#include "Mallocator.h"
 
 // sniffing types
 #define MAC_SNIFF_WIFI 0
@@ -87,9 +88,9 @@ extern char display_line6[], display_line7[]; // screen buffers
 extern uint8_t volatile channel;              // wifi channel rotation counter
 extern uint16_t volatile macs_total, macs_wifi, macs_ble,
     batt_voltage;                  // display values
-extern std::set<uint16_t> macs;    // temp storage for MACs
 extern hw_timer_t *channelSwitch, *sendCycle, *displaytimer;
 
+extern std::set<uint16_t, std::less<uint16_t>, Mallocator<uint16_t>> macs;
 extern std::array<uint64_t, 0xff>::iterator it;
 extern std::array<uint64_t, 0xff> beacons;
 
diff --git a/include/macsniff.h b/include/macsniff.h
index 81e5a2ed..d41fc787 100644
--- a/include/macsniff.h
+++ b/include/macsniff.h
@@ -6,8 +6,8 @@
 
 // Hash function for scrambling MAC addresses
 #include "hash.h"
-
 #include "senddata.h"
+#include "cyclic.h"
 
 #define MAC_SNIFF_WIFI 0
 #define MAC_SNIFF_BLE 1
diff --git a/include/mallocator.h b/include/mallocator.h
new file mode 100644
index 00000000..7d32d409
--- /dev/null
+++ b/include/mallocator.h
@@ -0,0 +1,54 @@
+/*
+
+This Mallocator code was taken from:
+
+CppCon2014 Presentations
+STL Features And Implementation Techniques
+Stephan T. Lavavej
+
+https://github.com/CppCon/CppCon2014      
+
+*/
+
+
+#ifndef _MALLOCATOR_H
+#define _MALLOCATOR_H
+
+#include <stdlib.h>          // size_t, malloc, free
+#include <new>               // bad_alloc, bad_array_new_length
+#include "esp32-hal-psram.h" // ps_malloc
+
+template <class T> struct Mallocator {
+  typedef T value_type;
+  Mallocator() noexcept {} // default ctor not required
+  template <class U> Mallocator(const Mallocator<U> &) noexcept {}
+  template <class U> bool operator==(const Mallocator<U> &) const noexcept {
+    return true;
+  }
+  template <class U> bool operator!=(const Mallocator<U> &) const noexcept {
+    return false;
+  }
+
+  T *allocate(const size_t n) const {
+    if (n == 0) {
+      return nullptr;
+    }
+    if (n > static_cast<size_t>(-1) / sizeof(T)) {
+      throw std::bad_array_new_length();
+    }
+    
+#ifndef BOARD_HAS_PSRAM
+    void *const pv = malloc(n * sizeof(T));
+#else
+    void *const pv = ps_malloc(n * sizeof(T));
+#endif
+
+    if (!pv) {
+      throw std::bad_alloc();
+    }
+    return static_cast<T *>(pv);
+  }
+  void deallocate(T *const p, size_t) const noexcept { free(p); }
+};
+
+#endif
\ No newline at end of file
diff --git a/include/rcommand.h b/include/rcommand.h
index 806f911a..269caf91 100644
--- a/include/rcommand.h
+++ b/include/rcommand.h
@@ -7,6 +7,7 @@
 #include "lorawan.h"
 #include "macsniff.h"
 #include <rom/rtc.h>
+#include "cyclic.h"
 
 // table of remote commands and assigned functions
 typedef struct {
diff --git a/platformio.ini b/platformio.ini
index e3423f2e..461cc403 100644
--- a/platformio.ini
+++ b/platformio.ini
@@ -30,13 +30,13 @@ description = Paxcounter is a proof-of-concept ESP32 device for metering passeng
 
 [common]
 ; for release_version use max. 10 chars total, use any decimal format like "a.b.c"
-release_version = 1.6.996
+release_version = 1.7.01
 ; DEBUG LEVEL: For production run set to 0, otherwise device will leak RAM while running!
 ; 0=None, 1=Error, 2=Warn, 3=Info, 4=Debug, 5=Verbose
 debug_level = 0
 ; UPLOAD MODE: select esptool to flash via USB/UART, select custom to upload to cloud for OTA
-;upload_protocol = esptool
-upload_protocol = custom
+upload_protocol = esptool
+;upload_protocol = custom
 extra_scripts = pre:build.py
 keyfile = ota.conf
 ;platform_espressif32 = espressif32@1.5.0
@@ -207,7 +207,7 @@ monitor_speed = ${common.monitor_speed}
 platform = ${common.platform_espressif32}
 framework = arduino
 board = esp32dev
-;board = t-beam
+;board = ttgo-t-beam
 board_build.partitions = ${common.board_build.partitions}
 upload_speed = 921600
 lib_deps = 
@@ -217,6 +217,7 @@ lib_deps =
 build_flags = 
     ${common.build_flags_all}
     -mfix-esp32-psram-cache-issue
+    -DBOARD_HAS_PSRAM
 upload_protocol = ${common.upload_protocol}
 extra_scripts = ${common.extra_scripts}
 monitor_speed = ${common.monitor_speed}
@@ -225,7 +226,7 @@ monitor_speed = ${common.monitor_speed}
 platform = ${common.platform_espressif32}
 framework = arduino
 board = esp32dev
-;board = t-beam
+;board = ttgo-t-beam
 board_build.partitions = ${common.board_build.partitions}
 upload_speed = 921600
 lib_deps = 
@@ -235,6 +236,7 @@ lib_deps =
 build_flags = 
     ${common.build_flags_all}
     -mfix-esp32-psram-cache-issue
+    -DBOARD_HAS_PSRAM
 upload_protocol = ${common.upload_protocol}
 extra_scripts = ${common.extra_scripts}
 monitor_speed = ${common.monitor_speed}
@@ -287,6 +289,7 @@ lib_deps =
 build_flags =
     ${common.build_flags_basic}
     -mfix-esp32-psram-cache-issue
+    -DBOARD_HAS_PSRAM
 upload_protocol = ${common.upload_protocol}
 extra_scripts = ${common.extra_scripts}
 monitor_speed = ${common.monitor_speed}
diff --git a/src/cyclic.cpp b/src/cyclic.cpp
index 137ea7f6..80e16f1f 100644
--- a/src/cyclic.cpp
+++ b/src/cyclic.cpp
@@ -55,19 +55,33 @@ void doHousekeeping() {
   ESP_LOGI(TAG, "Measured Voltage: %dmV", batt_voltage);
 #endif
 
-  // check free memory
-  if (esp_get_minimum_free_heap_size() <= MEM_LOW) {
+  // check free heap memory
+  if (ESP.getMinFreeHeap() <= MEM_LOW) {
     ESP_LOGI(TAG,
              "Memory full, counter cleared (heap low water mark = %d Bytes / "
              "free heap = %d bytes)",
-             esp_get_minimum_free_heap_size(), ESP.getFreeHeap());
+             ESP.getMinFreeHeap() , ESP.getFreeHeap());
     SendPayload(COUNTERPORT); // send data before clearing counters
     reset_counters();         // clear macs container and reset all counters
     get_salt();               // get new salt for salting hashes
 
-    if (esp_get_minimum_free_heap_size() <= MEM_LOW) // check again
+    if (ESP.getMinFreeHeap()  <= MEM_LOW) // check again
       do_reset(); // memory leak, reset device
   }
+
+// check free PSRAM memory
+#ifdef BOARD_HAS_PSRAM
+  if (ESP.getMinFreePsram() <= MEM_LOW) {
+    ESP_LOGI(TAG, "PSRAM full, counter cleared");
+    SendPayload(COUNTERPORT); // send data before clearing counters
+    reset_counters();         // clear macs container and reset all counters
+    get_salt();               // get new salt for salting hashes
+
+    if (ESP.getMinFreePsram() <= MEM_LOW) // check again
+      do_reset();                      // memory leak, reset device
+  }
+#endif
+
 } // doHousekeeping()
 
 // uptime counter 64bit to prevent millis() rollover after 49 days
@@ -80,6 +94,14 @@ uint64_t uptime() {
   return (uint64_t)high32 << 32 | low32;
 }
 
+uint32_t getFreeRAM() {
+#ifndef BOARD_HAS_PSRAM
+  return ESP.getFreeHeap();
+#else
+  return ESP.getFreePsram();
+#endif
+}
+
 void reset_counters() {
   macs.clear();   // clear all macs container
   macs_total = 0; // reset all counters
diff --git a/src/display.cpp b/src/display.cpp
index 63f56831..ff78ec2b 100644
--- a/src/display.cpp
+++ b/src/display.cpp
@@ -166,7 +166,7 @@ void refreshtheDisplay() {
   u8x8.setCursor(0, 5);
   u8x8.printf(!cfg.rssilimit ? "RLIM:off " : "RLIM:%-4d", cfg.rssilimit);
   u8x8.setCursor(10, 5);
-  u8x8.printf("%4dKB", ESP.getFreeHeap() / 1024);
+  u8x8.printf("%4dKB", getFreeRAM() / 1024);
 
 #ifdef HAS_LORA
   // update LoRa status display (line 6)
diff --git a/src/hal/ttgobeam_new.h b/src/hal/ttgobeam_new.h
index 45f77d3c..1a4552a9 100644
--- a/src/hal/ttgobeam_new.h
+++ b/src/hal/ttgobeam_new.h
@@ -13,18 +13,17 @@
 // BME680 sensor on I2C bus
 // don't forget to connect SDIO of BME680 to GND for selecting i2c addr 0x76
 //
-#define HAS_BME GPIO_NUM_21, GPIO_NUM_22 // SDA, SCL
+//#define HAS_BME GPIO_NUM_21, GPIO_NUM_22 // SDA, SCL
 
 #define HAS_LED GPIO_NUM_14 // on board green LED
 
 // user defined sensors
 //#define HAS_SENSORS 1 // comment out if device has user defined sensors
 
-#define HAS_DISPLAY U8X8_SSD1306_128X64_NONAME_HW_I2C
-// Pins for I2C interface of OLED Display
-#define MY_OLED_SDA (21)
-#define MY_OLED_SCL (22)
-#define MY_OLED_RST (NOT_A_PIN)
+//#define HAS_DISPLAY U8X8_SSD1306_128X64_NONAME_HW_I2C
+//#define MY_OLED_SDA (21)
+//#define MY_OLED_SCL (22)
+//#define MY_OLED_RST (NOT_A_PIN)
 //#define DISPLAY_FLIP  1 // use if display is rotated
 
 #define HAS_LORA 1       // comment out if device shall not send data via LoRa
diff --git a/src/hal/ttgobeam_old.h b/src/hal/ttgobeam_old.h
index e7d39287..f8e530fc 100644
--- a/src/hal/ttgobeam_old.h
+++ b/src/hal/ttgobeam_old.h
@@ -19,6 +19,12 @@
 // user defined sensors
 //#define HAS_SENSORS 1 // comment out if device has user defined sensors
 
+//#define HAS_DISPLAY U8X8_SSD1306_128X64_NONAME_HW_I2C
+//#define MY_OLED_SDA (21)
+//#define MY_OLED_SCL (22)
+//#define MY_OLED_RST (NOT_A_PIN)
+//#define DISPLAY_FLIP  1 // use if display is rotated
+
 #define HAS_LORA 1       // comment out if device shall not send data via LoRa
 #define CFG_sx1276_radio 1 // HPD13A LoRa SoC
 #define BOARD_HAS_PSRAM // use extra 4MB external RAM
diff --git a/src/macsniff.cpp b/src/macsniff.cpp
index 920ec091..b1e5ffcc 100644
--- a/src/macsniff.cpp
+++ b/src/macsniff.cpp
@@ -119,7 +119,8 @@ bool mac_add(uint8_t *paddr, int8_t rssi, bool sniff_type) {
              "%d Bytes left",
              added ? "new  " : "known",
              sniff_type == MAC_SNIFF_WIFI ? "WiFi" : "BLTH", rssi, buff,
-             hashedmac, macs_wifi, macs_ble, ESP.getFreeHeap());
+             hashedmac, macs_wifi, macs_ble, getFreeRAM());
+
 #ifdef VENDORFILTER
   } else {
     // Very noisy
diff --git a/src/main.cpp b/src/main.cpp
index 50eed5a8..2ba2268e 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -54,13 +54,14 @@ configData_t cfg; // struct holds current device configuration
 char display_line6[16], display_line7[16]; // display buffers
 uint8_t volatile channel = 0;              // channel rotation counter
 uint16_t volatile macs_total = 0, macs_wifi = 0, macs_ble = 0,
-                  batt_voltage = 0;      // globals for display
-
+                  batt_voltage = 0; // globals for display
 hw_timer_t *channelSwitch = NULL, *sendCycle = NULL, *homeCycle = NULL,
            *displaytimer = NULL; // irq tasks
 TaskHandle_t irqHandlerTask, wifiSwitchTask;
 
-std::set<uint16_t> macs; // container holding unique MAC adress hashes
+// container holding unique MAC address hashes with Memory Alloctor using PSRAM,
+// if present
+std::set<uint16_t, std::less<uint16_t>, Mallocator<uint16_t>> macs;
 
 // initialize payload encoder
 PayloadConvert payload(PAYLOAD_BUFFER_SIZE);
@@ -107,8 +108,10 @@ void setup() {
                                                          : "external");
   ESP_LOGI(TAG, "Internal Total heap %d, internal Free Heap %d",
            ESP.getHeapSize(), ESP.getFreeHeap());
+#ifdef BOARD_HAS_PSRAM
   ESP_LOGI(TAG, "SPIRam Total heap %d, SPIRam Free Heap %d", ESP.getPsramSize(),
            ESP.getFreePsram());
+#endif
   ESP_LOGI(TAG, "ChipRevision %d, Cpu Freq %d, SDK Version %s",
            ESP.getChipRevision(), ESP.getCpuFreqMHz(), ESP.getSdkVersion());
   ESP_LOGI(TAG, "Flash Size %d, Flash Speed %d", ESP.getFlashChipSize(),
@@ -124,7 +127,16 @@ void setup() {
   // read (and initialize on first run) runtime settings from NVRAM
   loadConfig(); // includes initialize if necessary
 
-  // initialize leds
+#ifdef BOARD_HAS_PSRAM
+  if (psramFound()) {
+    ESP_LOGI(TAG, "PSRAM found and initialized");
+    strcat_P(features, " PSRAM");
+  } else
+    ESP_LOGI(TAG, "No PSRAM found");
+#else
+#endif
+
+    // initialize leds
 #if (HAS_LED != NOT_A_PIN)
   pinMode(HAS_LED, OUTPUT);
   strcat_P(features, " LED");
diff --git a/src/paxcounter.conf b/src/paxcounter.conf
index 94cdfd1d..370a5ce3 100644
--- a/src/paxcounter.conf
+++ b/src/paxcounter.conf
@@ -81,7 +81,7 @@
 #define RESPONSE_TIMEOUT_MS             60000   // firmware binary server connection timeout [milliseconds]
 
 // setting for syncing time of node
-#define TIME_SYNC_INTERVAL              60      // sync time each ... minutes [default = 60], comment out means off          
+//#define TIME_SYNC_INTERVAL              60      // sync time each ... minutes [default = 60], comment out means off          
 
 // LMIC settings
 // moved to src/lmic_config.h
\ No newline at end of file
diff --git a/src/rcommand.cpp b/src/rcommand.cpp
index eebd7f30..3b6bccc6 100644
--- a/src/rcommand.cpp
+++ b/src/rcommand.cpp
@@ -245,7 +245,7 @@ void get_status(uint8_t val[]) {
 #endif
   payload.reset();
   payload.addStatus(voltage, uptime() / 1000, temperatureRead(),
-                    ESP.getFreeHeap(), rtc_get_reset_reason(0),
+                    getFreeRAM(), rtc_get_reset_reason(0),
                     rtc_get_reset_reason(1));
   SendPayload(STATUSPORT);
 };