diff --git a/firmware/targets/f7/api_symbols.csv b/firmware/targets/f7/api_symbols.csv
index 9623807ce..ea96eac8c 100644
--- a/firmware/targets/f7/api_symbols.csv
+++ b/firmware/targets/f7/api_symbols.csv
@@ -1,5 +1,5 @@
 entry,status,name,type,params
-Version,+,7.26,,
+Version,+,7.28,,
 Header,+,applications/services/bt/bt_service/bt.h,,
 Header,+,applications/services/cli/cli.h,,
 Header,+,applications/services/cli/cli_vcp.h,,
@@ -708,12 +708,12 @@ Function,+,dialog_message_show,DialogMessageButton,"DialogsApp*, const DialogMes
 Function,+,dialog_message_show_storage_error,void,"DialogsApp*, const char*"
 Function,-,difftime,double,"time_t, time_t"
 Function,-,digital_sequence_add,void,"DigitalSequence*, uint8_t"
-Function,-,digital_sequence_alloc,DigitalSequence*,"uint32_t, const GpioPin*"
+Function,-,digital_sequence_alloc,DigitalSequence*,uint32_t
 Function,-,digital_sequence_clear,void,DigitalSequence*
 Function,-,digital_sequence_free,void,DigitalSequence*
+Function,-,digital_sequence_send,_Bool,"DigitalSequence*, const GpioPin*"
 Function,-,digital_sequence_send_signal,_Bool,DigitalSignal*
 Function,-,digital_sequence_set_signal,void,"DigitalSequence*, uint8_t, DigitalSignal*"
-Function,-,digital_sequence_send,_Bool,DigitalSequence*
 Function,-,digital_signal_add,void,"DigitalSignal*, uint32_t"
 Function,-,digital_signal_alloc,DigitalSignal*,uint32_t
 Function,-,digital_signal_append,_Bool,"DigitalSignal*, DigitalSignal*"
diff --git a/firmware/targets/f7/furi_hal/furi_hal_nfc.c b/firmware/targets/f7/furi_hal/furi_hal_nfc.c
index b95d490af..c14016fc2 100644
--- a/firmware/targets/f7/furi_hal/furi_hal_nfc.c
+++ b/firmware/targets/f7/furi_hal/furi_hal_nfc.c
@@ -536,7 +536,7 @@ static bool furi_hal_nfc_transparent_tx_rx(FuriHalNfcTxRxContext* tx_rx, uint16_
     // Send signal
     FURI_CRITICAL_ENTER();
     nfca_signal_encode(tx_rx->nfca_signal, tx_rx->tx_data, tx_rx->tx_bits, tx_rx->tx_parity);
-    digital_signal_send(tx_rx->nfca_signal->tx_signal, &gpio_spi_r_mosi);
+    digital_sequence_send(tx_rx->nfca_signal->tx_signal, &gpio_spi_r_mosi);
     FURI_CRITICAL_EXIT();
     furi_hal_gpio_write(&gpio_spi_r_mosi, false);
 
diff --git a/lib/digital_signal/digital_signal.c b/lib/digital_signal/digital_signal.c
index 6dd29eff5..de79c2962 100644
--- a/lib/digital_signal/digital_signal.c
+++ b/lib/digital_signal/digital_signal.c
@@ -15,7 +15,6 @@
 
 DigitalSignal* digital_signal_alloc(uint32_t max_edges_cnt) {
     DigitalSignal* signal = malloc(sizeof(DigitalSignal));
-    signal->prepared = false;
     signal->start_level = true;
     signal->edges_max_cnt = max_edges_cnt;
     signal->edge_timings = malloc(signal->edges_max_cnt * sizeof(uint32_t));
@@ -65,8 +64,6 @@ bool digital_signal_append(DigitalSignal* signal_a, DigitalSignal* signal_b) {
     }
     signal_a->edge_cnt += signal_b->edge_cnt - start_copy;
 
-    signal_a->prepared = false;
-
     return true;
 }
 
@@ -236,6 +233,8 @@ void digital_signal_send(DigitalSignal* signal, const GpioPin* gpio) {
     /* Configure gpio as output */
     furi_hal_gpio_init(signal->gpio, GpioModeOutputPushPull, GpioPullNo, GpioSpeedVeryHigh);
 
+    /* single signal, add a temporary, terminating edge at the end */
+    signal->edge_timings[signal->edge_cnt++] = 10;
     digital_signal_prepare(signal);
 
     digital_signal_setup_dma(signal);
@@ -247,14 +246,15 @@ void digital_signal_send(DigitalSignal* signal, const GpioPin* gpio) {
 
     digital_signal_stop_timer();
     digital_signal_stop_dma();
+
+    signal->edge_cnt--;
 }
 
 
-DigitalSequence* digital_sequence_alloc(uint32_t size, const GpioPin* gpio) {
+DigitalSequence* digital_sequence_alloc(uint32_t size) {
 
     DigitalSequence* sequence = malloc(sizeof(DigitalSequence));
 
-    sequence->gpio = gpio;
     sequence->signals_size = 32;
     sequence->signals = malloc(sequence->signals_size * sizeof(DigitalSignal*));
 
@@ -282,7 +282,6 @@ void digital_sequence_set_signal(DigitalSequence* sequence, uint8_t signal_index
 
     /* all signals will use the sequence's GPIO */
     signal->gpio = sequence->gpio;
-    signal->prepared = false;
 
     digital_signal_prepare(signal);
 }
@@ -327,11 +326,13 @@ bool digital_sequence_send_signal(DigitalSignal* signal) {
     return true;
 }
 
-bool digital_sequence_send(DigitalSequence* sequence) {
+bool digital_sequence_send(DigitalSequence* sequence, const GpioPin* gpio) {
     furi_assert(sequence);
 
     uint32_t remainder = 0;
 
+    sequence->gpio = gpio;
+
     for(uint32_t pos = 0; pos < sequence->sequence_used; pos++) {
         DigitalSignal *sig = sequence->signals[sequence->sequence[pos]];
 
diff --git a/lib/digital_signal/digital_signal.h b/lib/digital_signal/digital_signal.h
index 583105e47..83ccbad30 100644
--- a/lib/digital_signal/digital_signal.h
+++ b/lib/digital_signal/digital_signal.h
@@ -14,10 +14,10 @@ extern "C" {
 #define DIGITAL_SIGNAL_MS(x) (x*100000000UL)
 #define DIGITAL_SIGNAL_US(x) (x*100000UL)
 #define DIGITAL_SIGNAL_NS(x) (x*100UL)
+#define DIGITAL_SIGNAL_PS(x) (x/10UL)
 
 
 typedef struct {
-    bool prepared;
     bool start_level;
     uint32_t edge_cnt;
     uint32_t edges_max_cnt;
@@ -50,12 +50,12 @@ uint32_t digital_signal_get_edge(DigitalSignal* signal, uint32_t edge_num);
 void digital_signal_send(DigitalSignal* signal, const GpioPin* gpio);
 
 
-DigitalSequence* digital_sequence_alloc(uint32_t size, const GpioPin* gpio);
+DigitalSequence* digital_sequence_alloc(uint32_t size);
 void digital_sequence_free(DigitalSequence* sequence);
 void digital_sequence_set_signal(DigitalSequence* sequence, uint8_t signal_index, DigitalSignal* signal);
 void digital_sequence_add(DigitalSequence* sequence, uint8_t signal_index);
 bool digital_sequence_send_signal(DigitalSignal* signal);
-bool digital_sequence_send(DigitalSequence* sequence);
+bool digital_sequence_send(DigitalSequence* sequence, const GpioPin* gpio);
 void digital_sequence_clear(DigitalSequence* sequence);
 
 
diff --git a/lib/nfc/protocols/nfca.c b/lib/nfc/protocols/nfca.c
index c401f8cc5..94f6a9e70 100644
--- a/lib/nfc/protocols/nfca.c
+++ b/lib/nfc/protocols/nfca.c
@@ -7,11 +7,10 @@
 
 #define NFCA_CRC_INIT (0x6363)
 
-#define NFCA_F_SIG (13560000.0)
-#define T_SIG 7374 //73.746ns*100
-#define T_SIG_x8 58992 //T_SIG*8
-#define T_SIG_x8_x8 471936 //T_SIG*8*8
-#define T_SIG_x8_x9 530928 //T_SIG*8*9
+#define NFCA_F_SIG  (13560000.0)                    /* [Hz] NFC frequency */
+#define NFCA_F_SUB  (NFCA_F_SIG/16)                 /* [Hz] NFC subcarrier frequency fs/16 */
+#define T_SUB       (1000000000000.0f / NFCA_F_SUB) /* [ps] subcarrier period = 1/NFCA_F_SUB */
+#define T_SUB_PHASE (T_SUB/2)                       /* [ps] a single subcarrier phase */
 
 #define NFCA_SIGNAL_MAX_EDGES (1350)
 
@@ -64,35 +63,25 @@ bool nfca_emulation_handler(
 }
 
 static void nfca_add_bit(DigitalSignal* signal, bool bit) {
-    if(bit) {
-        signal->start_level = true;
-        for(size_t i = 0; i < 7; i++) {
-            signal->edge_timings[i] = T_SIG_x8;
-        }
-        signal->edge_timings[7] = T_SIG_x8_x9;
-        signal->edge_cnt = 8;
-    } else {
-        signal->start_level = false;
-        signal->edge_timings[0] = T_SIG_x8_x8;
-        for(size_t i = 1; i < 9; i++) {
-            signal->edge_timings[i] = T_SIG_x8;
-        }
-        signal->edge_cnt = 9;
+
+    signal->start_level = bit;
+    for(size_t i = 0; i < 16; i++) {
+        signal->edge_timings[signal->edge_cnt++] = T_SUB_PHASE;
     }
 }
 
 static void nfca_add_byte(NfcaSignal* nfca_signal, uint8_t byte, bool parity) {
     for(uint8_t i = 0; i < 8; i++) {
         if(byte & (1 << i)) {
-            digital_signal_append(nfca_signal->tx_signal, nfca_signal->one);
+            digital_sequence_add(nfca_signal->tx_signal, 1);
         } else {
-            digital_signal_append(nfca_signal->tx_signal, nfca_signal->zero);
+            digital_sequence_add(nfca_signal->tx_signal, 0);
         }
     }
     if(parity) {
-        digital_signal_append(nfca_signal->tx_signal, nfca_signal->one);
+        digital_sequence_add(nfca_signal->tx_signal, 1);
     } else {
-        digital_signal_append(nfca_signal->tx_signal, nfca_signal->zero);
+        digital_sequence_add(nfca_signal->tx_signal, 0);
     }
 }
 
@@ -102,7 +91,7 @@ NfcaSignal* nfca_signal_alloc() {
     nfca_signal->zero = digital_signal_alloc(10);
     nfca_add_bit(nfca_signal->one, true);
     nfca_add_bit(nfca_signal->zero, false);
-    nfca_signal->tx_signal = digital_signal_alloc(NFCA_SIGNAL_MAX_EDGES);
+    nfca_signal->tx_signal = digital_sequence_alloc(NFCA_SIGNAL_MAX_EDGES);
 
     return nfca_signal;
 }
@@ -112,7 +101,7 @@ void nfca_signal_free(NfcaSignal* nfca_signal) {
 
     digital_signal_free(nfca_signal->one);
     digital_signal_free(nfca_signal->zero);
-    digital_signal_free(nfca_signal->tx_signal);
+    digital_sequence_free(nfca_signal->tx_signal);
     free(nfca_signal);
 }
 
@@ -121,17 +110,19 @@ void nfca_signal_encode(NfcaSignal* nfca_signal, uint8_t* data, uint16_t bits, u
     furi_assert(data);
     furi_assert(parity);
 
-    nfca_signal->tx_signal->edge_cnt = 0;
-    nfca_signal->tx_signal->start_level = true;
-    // Start of frame
-    digital_signal_append(nfca_signal->tx_signal, nfca_signal->one);
+    digital_sequence_clear(nfca_signal->tx_signal);
+
+    /* add a >80/fs phase with no transition, which is >10 1-bits */
+    for(int tr1_bit = 0; tr1_bit < 11; tr1_bit++) {
+        digital_sequence_add(nfca_signal->tx_signal, 1);
+    }
 
     if(bits < 8) {
         for(size_t i = 0; i < bits; i++) {
             if(FURI_BIT(data[0], i)) {
-                digital_signal_append(nfca_signal->tx_signal, nfca_signal->one);
+                digital_sequence_add(nfca_signal->tx_signal, 1);
             } else {
-                digital_signal_append(nfca_signal->tx_signal, nfca_signal->zero);
+                digital_sequence_add(nfca_signal->tx_signal, 0);
             }
         }
     } else {
diff --git a/lib/nfc/protocols/nfca.h b/lib/nfc/protocols/nfca.h
index 498ef2843..aad1a4fd8 100644
--- a/lib/nfc/protocols/nfca.h
+++ b/lib/nfc/protocols/nfca.h
@@ -8,7 +8,7 @@
 typedef struct {
     DigitalSignal* one;
     DigitalSignal* zero;
-    DigitalSignal* tx_signal;
+    DigitalSequence* tx_signal;
 } NfcaSignal;
 
 uint16_t nfca_get_crc16(uint8_t* buff, uint16_t len);
diff --git a/lib/nfc/protocols/nfcv.c b/lib/nfc/protocols/nfcv.c
index aed0023cd..42dbd0ded 100644
--- a/lib/nfc/protocols/nfcv.c
+++ b/lib/nfc/protocols/nfcv.c
@@ -215,7 +215,7 @@ void nfcv_emu_alloc() {
     
     if(!nfcv_signal) {
         /* assuming max frame length is 255 bytes */
-        nfcv_signal = digital_sequence_alloc(8 * 255 + 2, nfcv_out_io);
+        nfcv_signal = digital_sequence_alloc(8 * 255 + 2);
     }
 
     if(!nfcv_resp_unmod_256) {
@@ -297,7 +297,7 @@ void nfcv_emu_send_raw(uint8_t* data, uint8_t length) {
     digital_sequence_add(nfcv_signal, SIG_EOF);
 
     FURI_CRITICAL_ENTER();
-    digital_sequence_send(nfcv_signal);
+    digital_sequence_send(nfcv_signal, nfcv_out_io);
     FURI_CRITICAL_EXIT();
     furi_hal_gpio_write(nfcv_out_io, false);
 }