The reasons why you get picture Freeze is due to a few common problems with digital signals in general. Digital signals are more affected than analogue signals by poor carrier to noise and impulse noise. Of course, other forms of interference affect both analogue and digital signals, but impulse noise is by its very definition impulsive. The susceptibility of DTT signals to impulse noise is an important factor when making a good digital installation since it interrupts the data stream of picture information & corrupts that data. This can result in locked pictures, pixilation or total blanking. The well known ones are car ignition picked up on the aerial, electric fences, mercury arc lighting, or a home heating thermostat arcing causing spikes which travel through the coax cable. Both will eventually arrive at the digital tuner. Although increasing the signal level could help by improving the carrier to noise ratio, impulse noise is often greater than the wanted signal.
It is not difficult to protect the digital signal from impulse noise by using well screened components. However a TV Aerial is designed to collect signals, so cannot be screened. What a good aerial does is collect only the good signal and reject the bad signals.
The Log Periodic TV Aerial is ideal for the purpose as it rejects the impulse noise noise by a 15db margin whilst picking up the good TV signal just like a high gain aerial would. We generally will only use theseย TV Aerials in our installationsย for obvious reasons.