diff --git a/Components/1770/1770.cpp b/Components/1770/1770.cpp
index 383a2eb41..6e2011f45 100644
--- a/Components/1770/1770.cpp
+++ b/Components/1770/1770.cpp
@@ -403,7 +403,7 @@ void WD1770::posit_event(Event new_event_type) {
 			goto verify;
 		}
 		step(step_direction_ ? 1 : -1);
-		int time_to_wait;
+		unsigned int time_to_wait;
 		switch(command_ & 3) {
 			default:
 			case 0: time_to_wait = 6;	break;
diff --git a/Storage/Tape/Formats/TZX.cpp b/Storage/Tape/Formats/TZX.cpp
index 37b0cb169..6814b8bcd 100644
--- a/Storage/Tape/Formats/TZX.cpp
+++ b/Storage/Tape/Formats/TZX.cpp
@@ -126,7 +126,7 @@ void TZX::get_generalised_segment(uint32_t output_symbols, uint8_t max_pulses_pe
 		base <<= 1;
 		bits++;
 	}
-	for(int c = 0; c < output_symbols; c++) {
+	for(size_t c = 0; c < output_symbols; c++) {
 		uint8_t symbol_value;
 		int count;
 		if(is_data) {