You've reached our premium or archival content
To access this page, and more great content just like it, you need to become a paid subscriber.
If you already have an account, please login.
Otherwise, registration is quick and you'll have access instantly after payment.
As it has been pointed out previously by CRA digital broadcasting is the cheapest way of getting the program from a studio to a large audience.
If all of the audience use smart speakers and landline & mobile phones and there is an emergency these devices will not work meaning no warnings when no one owns a radio.
In the recent fires the tower serving Bateman's Bay/Moruya was burnt. This stopped mobile phones and wireless internet from working. Even without burning the tower the power line to the site is burnt down, Fire controllers will not allow a tanker filled with diesel to drive to the tower site to replenish the generator every day.
Remember also that lots of Australians have Fibre to the Node NBN and if the power fails in that street, when the batteries in the Node cabinet go flat, the smart speaker and the computers will no longer receive warnings. This also applies to mobile phone base stations as well.
Mr StJohn made a valuable observation in regards a power failure in an FTTN (fibre to the node) connection where smart speakers may be utilized in an emergency situation.
Here are applications for various connection types such as FTTP, FTTB, FTTC, FTTN, HFC and Sky Muster™ which may apply to broadcasting stations and households.
FTTP (fibre to the premises) - a fibre optic cable is connected to the premises. There is no electrical connection from the fibre optic cable to the premises. Power is required to power up the network terminal device ('NTD'), the interface between the fibre optic cable and the provider's router.
If there is a power blackout, two-way communications is not possible to the fibre optic cable's NTD. However an external battery may allow operation of the NTD and router for a specified number of hours depending on the capacity of the battery. Typically it's 4 hours according to the NBNCo.
Remark not mentioned on the NBNCo site: While the fibre optic cable continues to emit light during a power blackout, there is NOTHING to indicate the source of powering the fibre optic cable transceivers (transmitter/receiver). For example if the power goes out at the transceiver's source - that is where is the power source of the fibre optic cable system?
FTTB (fibre to the building) - even though there is a fibre optic to the building, unlike FTTP, there is no ability to connect a power backup system during a power blackout.
Remark: In such a situation, for radio studios using IP communications from the studio to the tx, the radio station should seek an alternative to FTTB including installing FTTP and/or a microwave link from studio to tx.
FTTC (fibre to the curb) - a fibre optic cable runs in front of the premises. Four premises are connected to a hub located in the pit. Each premises uses a copper cable from the hub to the premises. Power is required to power the hub from the premises.
In a blackout, no two-way communication is possible using FTTC. However a backup system is possible through the use of a battery backup to power the FTTC's NTD and router connected to the NTD.
Remark not mentioned on the NBNCo site: laser light from the fibre optic cable terminates at the hub. The particular hub connection to the premises requires hub. Suppose there is backup power in the premises, like FTTP, there is nothing to indicate in the NBNCo's website the source of power of the fibre optic transceivers (transmitter/receiver).
FTTN (fibre to the node) - a fibre optic cable runs to a node. The node is powered by the mains and should there be a power failure there is a battery backup located in the node. Within the node, there are interfaces between the fibre optic cable and the copper wire for each household. The household's copper cable is interfaced to a NTD and then router.
In a blackout, the household's NTD and provider's router will not operate. No backup battery of the NTD and provider's router is possible at the premises. The only backup is possible at the node.
Remark not mentioned on the NBNCo site: StJohn mentioned that if the node's backup battery fails, then communication via the internet and voip telephone fail.
HFC (hybrid fibre coaxial) - if a blackout occurs, backup power is not possible at the premises at all.
FW (fixed wireless) - during a blackout, no backup power is possible especially if the fixed wireless towers have no backup.
Remark: for households, have a mobile phone as as backup. For radio studios, consider using alternative means of communicating between studio and tx such as a microwave link.
According to the NBNCo, in such a situation, where a "...premises is located within a Fixed Wireless and Sky Muster™ satellite area...", the householder "...will have the option of keeping the existing landline phone service active across the copper network....." Source NBNCo.
Sky Muster™ satellite - power backup is possible. But if the satellite loses power, the household may still have access to the 'landline' (POTS) system. Householders may need to talk to the provider.
I avert readers to the NBNCo's information on power failures to the various methods of NBN connection:
Source:
https://www.nbnco.com.au/learn/what-happens-in-a-power-blackout
Thank you,
Anthony of exciting Belfield
Here is an further angle to the powering of NBN services. My mother in law is in her 80s and has one of those emergency call systems around her neck for medical emergencies. She was recently 'upgraded' to the NBN. Then her emergency call system told her that the phone lines supplied by the NBN would not be powered during a blackout and that she should convert to a SIM powered mobile system. Thankfully the government has realised the problem and offers subsidies to cover the cost of that... but why is this not talked about when discussing the NBN roll out. It seems that it would be an important thing to be aware of. Thanks to StJohn and AnthonyKoala for discussing it.
May I also add a further detail about the FTTC (fibre to the curb) powering the NBN's NTD (network terminal device). It may not have been so obvious in my previous remark.
As at 06-03-2020, the NTD's power supply is from the mains. There is no DC transformer adapter to convert the 240VAC mains to the NTD's operating current.
That is you cannot supply the NTD with DC current externally.
Also the NTD does not accommodate spare space for an SLA 12V battery like the FTTP's NTD.
References to show that there is no space to accommodate an emergency battery for the NTD.
https://www.nbnco.com.au/learn/network-technology/fibre-to-the-curb-explained-fttc
And page 3 of
https://www.nbnco.com.au/content/dam/nbnco2/2018/documents/FTTC_Setup_Guide_1830077.pdf
There's hope - you can connect a power supply to the FTTC's NTD:
While it appears that you cannot provide a backup, one can use an inverter/charger/ups with a 12V backing battery. The 12V battery connected to the UPS can last even longer than the 'advertised' running time of 4 hours.
Distinction between NTD and router - applied to the FTTC:
The NTD refers to the connection box between the NBN's line and the provider's router. The provider's router refers to router supplied by one's preferred retailer of telephonic and internet services. This router is connected to the NTD and provides connections to a phone (with tone dialling NOT rotary dialling) and internet (data). Follow the instructions of one's provider's router,
This applies to households and radio broadcasters who use the internet for transmitting and receiving broadcast audio.
Thank you,
Anthony of Belfield