diff --git a/Machines/Apple/AppleII/SCSICard.cpp b/Machines/Apple/AppleII/SCSICard.cpp
index 5d18adf3b..9e0e83dd0 100644
--- a/Machines/Apple/AppleII/SCSICard.cpp
+++ b/Machines/Apple/AppleII/SCSICard.cpp
@@ -167,3 +167,7 @@ void SCSICard::perform_bus_operation(Select select, bool is_read, uint16_t addre
 void SCSICard::set_storage_device(const std::shared_ptr<Storage::MassStorage::MassStorageDevice> &device) {
 	storage_->set_storage(device);
 }
+
+void SCSICard::set_activity_observer(Activity::Observer *observer) {
+	scsi_bus_.set_activity_observer(observer);
+}
diff --git a/Machines/Apple/AppleII/SCSICard.hpp b/Machines/Apple/AppleII/SCSICard.hpp
index 8ce7ce20d..0859730b1 100644
--- a/Machines/Apple/AppleII/SCSICard.hpp
+++ b/Machines/Apple/AppleII/SCSICard.hpp
@@ -37,6 +37,8 @@ class SCSICard: public Card {
 			scsi_bus_.run_for(cycles);
 		}
 
+		void set_activity_observer(Activity::Observer *observer) final;
+
 	private:
 		uint8_t *ram_pointer_ = nullptr;
 		uint8_t *rom_pointer_ = nullptr;