Those affected suburbs include Crescent Heads, Port Macquarie, Wauchope, Bonny Hills, Harrington, Taree and some parts of Forster.

It is expected that these moves will free up broadcasting spectrum that will be used for new services such as mobile broadband.

Once the channels have moved, viewers will need to retune their digital TV, set-top box or digital TV recorder to get them back.

Retuning is done using the remote. For most systems, viewers should press the 'menu' button on the remote; look for settings such as 'channels' or 'auto-tuning', then follow the prompts to retune.

A video and 3-step guide to retuning is available on the website. Go to: www.retune.digitalready.gov.au.

You may want to write down your favourite channel, program recordings or parental lock settings before they retune as retuning may delete these settings.

There may be some disruption to all TV services for several hours today due to work being conducted at the transmission site. Viewers should wait until after the expected retune time of 3:30pm before retuning.

Viewers are reminded that there may also be outages to all TV services over the next two days but there is no need to retune again; the TV services will reappear once the work at the transmission site has been completed.

Other residents in Hastings and Manning Valley may experience some disruption to TV services from September 10-11.

People living in apartments may be using a shared antenna system. If channels do not reappear after retuning, they should contact their property manager or body corporate.

Viewers can find information about how to retune and any scheduled retune outages on the website below or by calling the Digital Ready Information Line.

Anyone who experiences difficulty retuning their equipment should check their manufacturer's handbook or manual for instructions on how to retune, ask a friend or family member to help, visit the retune website, or call the Digital Ready Information Line on 1800 20 10 13, 8am to 10pm (AEST), 7 days.