 DTV broadcasts exhibit a digital cliff effect, by which viewers will receive either a perfect signal or no signal at all with little or no middle ground.Digital transmissions do contain additional data bits to provide error correction for a finite number of bit errors; once signal quality degrades beyond that point, recovery of the original digital signal becomes impossible, and the image on the screen freezes, or blinks back and forth to totally blank black.The maximum power for DTV broadcast classes is also substantially lower; one-fifth of the legal limits for the former full-power analog services.