More recently, high-end hobby systems using Pulse-Code Modulation (PCM) features have come on the market that provide a digital bit -stream signal to the receiving device instead of analog type pulse modulation. Advantages include bit error checking capabilities of the data stream (good for signal integrity checking) and fail-safe options including motor (if the model has a motor) throttle down and similar automatic actions based on signal loss. However, those systems that use pulse code modulation generally induce more lag due to lesser frames sent per second as bandwidth is needed for error checking bits. PCM devices can only detect errors and thus hold the last verified position or go into failsafe mode. They cannot correct transmission errors.