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There’s absolutely nothing wrong with this
currently legal, dual channel, dual-diversity
Digitech wireless microphone system from
Jaycar . . . except that using it after December
31 could land you with a fine – all because it
operates in what will be a banned frequency
range. Jaycar have now replaced this with a
legal (520-694MHz) model.
By
ROSS TESTER
Is Your Wireless Microphone
soon to be illegal ?
A huge proportion of the wireless microphones now being used in
Australia will soon lose their licences to operate. If you keep using
them after December 31st, you could be liable for a big fine. We
return to this rather thorny subject.
W
e covered the changes to Wireless Microphones
in some detail in the June 2013 issue but with
the December 31 deadline looming, it is timely
to look again at the reasons for the changes in legislation
and regulations which could affect a lot of clubs, non-profit
organisations and other users of so-called ‘plug and play’
wireless microphones.
First, a brief recap: the Labor Government sold off a large
chunk of the UHF band, previously occupied by analog TV
stations, as part of the Australia-wide move to digital TV.
Digital TV doesn’t require anything like the bandwidth of
analog, so those stations which used to transmit in the 694820MHz band have all been “restacked” (or the very last are
in the process of moving) to the 520-694MHz band.
This so-called ‘Digital Dividend’ reaped billions of dollars
for the Government as it was sold off to telecommunications
organisations for 4G data/voice expansion.
The problem was, and is, that a huge number of wireless
microphones and other wireless audio devices, particularly
28 Silicon Chip
the lower-end models, also shared the 694-820MHz band,
slotted in between the old UHF TV transmitters.
It is these wireless microphones (and other wireless devices)
which will become illegal to use from January 1st, 2015.
How many?
Quite a few years ago, the industry association put the
number of wireless microphones in use in Australia at
above 300,000.
Just about every club, public and private hall, reception
centre, theatre group, place of worship, sporting arena,
shopping centre and store, local council, sports coach and
fitness/dance instructor, hotel and restaurant and many
other venues have one or more (in some cases many more)
wireless microphones.
One local club I am familiar with has six, used for wedding receptions, functions and sports events. In the main,
venues like these use the lower-cost models which, while
perhaps not offering the fidelity and flexibility of more
siliconchip.com.au
professional models, are fine for the
intended purpose. They’re convenient,
allow freedom of movement without
cords to trip over and the better ones
provide a quality of signal that’s every
bit as good as fixed microphones.
Until the last couple of years or so,
the vast majority of these wireless
microphones used that higher (694820MHz) band and this is still mainly
the case for the lower-cost mics which
were sold in their tens of thousands
by music stores, electronics stores, at
markets and, in particular, online.
There are many thousands more
professional wireless microphones
in use which operate at much higher
(legal) frequencies – mainly around
1.8GHz – but these are not affected by
the changes.
To compound this, we knew from
experience that huge numbers of wireless microphones weren’t sourced from
“professional” suppliers (the ones who
knew the new rules) but instead were
purchased online from sources like
Gumtree, ebay, Trading Post etc.
Even as late as last month, you could
still buy significant numbers of highUHF band wireless microphones online, without the compulsory warning
attached that they would not be usable
from January 1 2015 (that warning is an
ACMA requirement, part of the LIPD
licence under which these things operate. It is that LIPD licence that will be
withdrawn on December 31).
Some of that equipment is being offered for less than (often much less than)
$100. Compare this to the professional
gear used by TV studios, entertainment
This Okayo portable PA system may
Got a Portable PA?
venues and the like, which is often many
be OK (o!) but more than likely is
We’re not just talking about wireless
hundreds of dollars, if not thousands.
not! It was sold with a wireless mic
mic and receiver setups: huge numbers
Perhaps just as disturbing is the numfrequency of between 640MHz (just
of “portable PA systems” have been
ber
of “Professional VHF” (whatever
OK) and 865MHz (not OK!).
sold over the years, many of which
that means!) systems still being flogged
have an inbuilt wireless microphone receiver. You often see online. Try using one of these in a capital city even now,
them used in shopping centres by store spruikers; buskers with the VHF band from 181 to 230MHz wall-to-wall with
use battery-powered models, they’re used for public meet- digital TV and DAB+ radio. There are also a handful of
ings and so on.
country areas which have retained VHF TV – the Manning
Again, the vast majority of these will become obsolete – Valley (NSW lower north coast) is one such area.
the amplifier itself may still be quite OK but the wireless
Even if your VHF Wireless Microphone is below 180MHz
microphone connecting to it will not. Some of these may be (and a lot of the ones we’ve seen even now for sale are, espeupgradeable but most will not. The only option to stay legal cially around 170MHz or so) you’re still in trouble, because
will be to use a corded microphone or to connect a new (ex- with the digital TV restacking the old VHF channels 0 to 5A
ternal) wireless mic receiver to the “line in” or “aux” input. (56 to 181MHz) have all gone and the LIPD licences for equipIncidentally, it was one of these systems which twigged us
ment using those frequencies have also been withdrawn.
to the whole sorry saga early last year, when a relative who
By the way, while the Government has made no effort to
used a local council portable PA asked us if we’d heard that recompense existing users of soon-to-be-banned equipment,
they were soon to be outlawed. At that stage, we hadn’t – so quite a number of suppliers have put together “trade-in”
much for the industry-wide consultation!
deals. Most of these offer the more expensive “pro” equipBy the way, Bluetooth wireless mics, which are used ment but they could be worth a look if the trade-in makes
with quite a few portable systems, are not affected. They the deal sweet enough.
will remain legal as they operate in the 2.4GHz band like
Local TV translators can still cause problems
all other Bluetooth devices.
With the move to digital TV and the re-stacking of chanCriticism
nels, a lot of areas are not served by the main city, high-power
Following our June 2013 report, we were roundly criticised transmitters but by lower-power translators.
by the association representing the professional end of the
So even if you do buy a legal (520-694MHz) wireless micmarket for saying that most wireless mics were in the upper, rophone you could still be in trouble, because part of the
and soon to be withdrawn, UHF band.
LIPD licence specifies that you must not use any frequency
They claimed that their association had worked closely which a local broadcasting service occupies.
with the Government (and ACMA, the regulatory body), to
“Local” might cover a lot greater area than you think – for
ensure that their members knew the new requirements and example, many TV viewers along Sydney’s northern beaches
only sold ‘future proof’ equipment, operating in that 520- receive their TV signals only from Bouddi Head, on the
694MHz band.
NSW Central Coast.
And we’re sure they did. But as late as last year, when
Similarly, many residents in Sydney’s south have to watch
our report was written, we found that many retailers were TV programs from the Wollongong area. In both these examstill selling 694-820MHz equipment. But that wasn’t the real ples, terrain prevents signals from the Sydney transmitters
problem. It was all those tens (hundreds?) of thousands of from avoiding the ‘digital cliff’. You’ve either got a picture
users who had bought, in good faith, lower-cost wireless or you haven’t; with digital TV there’s no ‘in-between’.
microphones which would be outlawed – without any form
There are several websites which show the areas digital
of recompense or subsidy.
TV stations are, or very shortly will be, transmitting in along
siliconchip.com.au
August 2014 29
the NSW coast, and their frequencies. With the exception of
the 520-526MHz soon-to-be-packed-out band, you will probably find that there are many areas where finding an unused
frequency is almost impossible; you need to choose the best
of a bad situation. Country areas aren’t quite so packed.
Our experience
Legend
YES
Available for wireless microphone use.
LIKELY
This frequency is likely to be available for wireless microphone use. However, it is possible that you may
receive interference from distant television and radio services in some areas. Seek advice from your supplier
to determine whether this frequency is suitable for your needs.
POSSIBLE
This frequency is possibly available for wireless microphone use. However, many locations will be prone
to receiving interference from television and radio services or causing interference especially when using
the wireless microphone outdoors. Seek advice from your supplier to determine whether this frequency is
suitable for your needs.
NO
Not available for wireless microphone use.
Available spectrum for wireless microphones from 1 January 2015
Location
Band
VHF
TV
channel
6, 7, 8, 10,
11, 12
27
UHF
Frequency
(MHz)
174–195
209–230
520–526
526–568
(see Note 3)
28, 29, 30,
31, 32, 33
34, 35, 36,
37, 38, 39
40, 41, 42,
43, 44, 45
46, 47, 48,
49, 50, 51
568–610
610–652
652–673
673–694
Sydney
NO
YES
NO
POSSIBLE
NO
Central Coast
LIKELY
LIKELY
NO
YES
LIKELY
NO
NO
NO
YES
Agnes Banks
NO
YES
NO
NO
NO
YES
YES
Appin
NO
YES
NO
NO
NO
NO
NO
Bargo
NO
YES
NO
NO
NO
NO
NO
Belimbla Park
NO
YES
NO
NO
NO
NO
NO
Blackheath
NO
YES
NO
NO
NO
YES
YES
Bowen Mountain
NO
YES
NO
NO
NO
YES
YES
Brooklyn
NO
YES
YES
YES
YES
NO
NO
Bundeena
NO
YES
NO
NO
YES
YES
YES
Buxton
NO
YES
NO
NO
NO
YES
YES
Catherine Field
NO
YES
NO
NO
NO
NO
NO
Cobbitty
NO
YES
NO
NO
NO
YES
YES
Couridjah
NO
YES
NO
NO
NO
YES
YES
Cowan
NO
YES
NO
NO
YES
YES
YES
Dangar Island
NO
YES
YES
YES
YES
YES
YES
Douglas Park
NO
YES
YES
NO
YES
NO
Freemans Reach
NO
YES
NO
NO
NO
NO
NO
Galston
NO
YES
NO
NO
NO
YES
YES
Surrounding areas
NO
Glenorie
NO
YES
NO
NO
NO
YES
YES
Glossodia
NO
YES
NO
NO
NO
YES
YES
Grasmere
NO
YES
YES
NO
NO
YES
YES
Hazelbrook
NO
YES
NO
NO
NO
NO
POSSIBLE
Jilliby
NO
YES
YES
NO
NO
NO
NO
Katoomba
NO
YES
NO
NO
NO
NO
POSSIBLE
Kirkham
NO
YES
YES
NO
NO
YES
YES
Kurmond
NO
YES
NO
NO
NO
YES
YES
Kurrajong
NO
YES
NO
NO
NO
YES
YES
Kurrajong Heights
NO
YES
NO
NO
NO
YES
YES
Lawson
NO
YES
NO
NO
NO
NO
POSSIBLE
Leppington
NO
YES
NO
NO
NO
YES
YES
Linden
NO
YES
NO
NO
NO
YES
YES
Silverdale-Warragamba
NO
YES
NO
NO
NO
YES
YES
YES
NO
NO
NO
NO
NO
YES
NO
NO
NO
NO
NO
This
spreadsheetNOon theYESACMA
lists
Luddenham
YESwebsite
NO
NO towns
NO and NO
Maianbar
NO
YES
NO
NO
YES
suburbs
throughout
Australia
with the
six YES
UHF and
oneYES
Medlow Bath
NO
YES
NO
NO
YES
YES
YES
Menangle
NO
YES
NO
NO
NO
YES
VHF bands listed with a YES/LIKELY/POSSIBLE/NO YES
Menangle Park
NO
YES
YES
NO
NO
YES
indication
of whether
wireless
mics YES
in those
bands
can YES
be
Mooney Mooney
NO
YES
YES
YES
YES
YES
Mount
Vernon
NO
YES
NO
NO
NO
NO
NO
used in that area. As you can see from the generally yellow
Mount Victoria
NO
YES
YES
NO
YES
YES
YES
(‘NO’)
boxes in this
areas
you’re
going
toYES
Mulgoa
NO chart,
YES in many
NO
NO
NO
YES
Oakdale
NO
YES
NO
NO
NO
YES
YES
be
pretty limited NO
for choice.
The
URL
for this
siteYES
is a mile
Orchard Hills
YES
NO
NO
NO
YES
long
accessYES
it by Googling
Fact
Patonga but you can NO
YES
YES “ACMA
YES
NO sheets
NO
Picton
YES
YES
NO
NO
YES
YES
and
FAQs” – it’s the
first
entryNO– click
on that,
then
clickYES
on
Pitt Town
NO
YES
NO
NO
YES
YES
the
town
want. NO
Richmond
North or suburb
NO youYES
NO
NO
YES
YES
Tahmoor
NO
30 S
ilicon Chip
The Oaks
NO
Thirlmere
NO
YES
NO
NO
NO
NO
NO
Wallacia
NO
YES
NO
NO
NO
YES
YES
We mentioned earlier that we have considerable experience in audio/PA and, by extension, wireless microphones.
Over the past 12 months or so we’ve talked to literally scores
of ‘average’ (ie, not professional) wireless microphone users
and with just one exception, there was complete ignorance
about the forthcoming changes.
These users were in the main sporting clubs, reception
venues and the like and they simply hadn’t heard ANYTHING about their equipment being outlawed.
The reaction was even more disturbing: they couldn’t give
a damn. “Let them catch me” was a typical response. “I’ll go
on using it until someone tells me to stop” was common. Or
the old shrug of the shoulders and “so what?” expression.
That one exception was a sporting organisation who does
use a professional technician to supply and maintain their
equipment. They’d just upgraded their whole PA system and
part of that deal was new 500MHz wireless microphones,
because their supplier knew the new requirements.
But the rest? They can be assured that there will one day
be a knock on the door, not necessarily from ACMA but
from one of the telcos who’s just forked out a LOT of money
(Billion$!) for the right to use clean spectrum.
As soon as there is any report of interference by their
customers, you can bet your bottom dollar (or billions of
dollars!) that they will ‘search and destroy’ all offenders.
So what to buy?
If you’re in the market for a wireless microphone (and if
you currently use one, that description probably fits you!)
there are a couple of things you should look for:
(a) Naturally, you must choose a wireless microphone in
that 520-694MHz band. Don’t be tempted by descriptions
which claim “approved frequencies” or some such if they
aren’t in that band. They aren’t (approved, that is).
(b) Take careful note of the digital TV frequencies being
used in your area – and surrounds. Choose a microphone
well away from these frequencies.
(c) While theoretically within the TV band, 520-526MHz is
currently unused by any TV channel, anywhere in Australia
– so a wireless microphone in that frequency range should
remain usable anywhere for at least the foreseeable future.
However, there is no guarantee that this band (TV channel
27) will not be taken up somewhere down the track (after
all, they took 694-820MHz away!). And as we mentioned
earlier, 520-526MHz is likely to become VERY crowded!
(d) If at all possible, choose a wireless microphone that is
‘frequency agile’ – that is, you can adjust its operating frequency (usually by pushing buttons). Of course, the receiver
will need to have the same feature but if they are sold as a
system, that’s pretty much taken for granted.
The better wireless microphone systems are almost always
frequency-agile but it is often found on cheaper ones as well.
(e) Buy from a reputable source and get a money-back
guarantee in case you find it can’t be used in your area. That’s
why it is usually preferable to buy from a bricks-and-mortar
store than online, even if you do have to pay a little more.
siliconchip.com.au
If you do buy online, choose an Australian supplier who
you can track down!
Need more info?
There’s a lot more information available on the ACMA
website which, if you’re interested in wireless mics and/or
digital TV, makes interesting reading. It’s just a pity that so
few people know anything about this resource.
So to summarise: if you have a wireless microphone which
works in the 694-820MHz band, you need to buy a new one
before December 31 this year and preferably one which is
‘frequency-agile’ so it can be set to suit your location. Don’t
assume that you won’t be affected. At the worst, you could
be fined or digital TV interference could simply blot your
microphone out. Depending on the situation, that could be
even more embarrassing.
Operating Wireless Microphones in UHF TV Areas:
even now there are traps for young players!
Over the past few months, I’ve been using the PA system
referred to in the main article, the one which had the new approved wireless microphones, for outdoor sports. It was being
used in a ‘portable’ mode; that is, the PA was erected at a specific
venue for one or two days, then packed away.
The first few times I used it, up and down the NSW coast, it
performed flawlessly. The wireless microphones had more than
enough range (I estimated 250m line of sight) but the most recent
occasion, in the Illawarra region of NSW, the range was woeful –
perhaps 10m or so but very intermittent. So what had changed?
The first thing I did was ensure that the wireless mic receiver
antennas weren’t being shielded – that’s a common problem.
Even damp or wet bricks in a building wall can chop the range
way down. I elevated the receiver so it had perfect line-of-sight
through a window. Nope – no change!
Batteries? Most microphones these days operate on one or
two “AA” cells, which obviously don’t last forever. I replaced the
batteries and . . . scratch that one!
Speaking of scratching, I was: my head, that is. I raised my
eyes to the heavens for inspiration . . . and the answer stared
back at me! I was in the northern suburbs of Wollongong and I
was looking straight up at the TV transmitters on Broker’s Nose,
a prominent point on the Illawarra escarpment which was probably no more than 3-4km away as the crow flies.
“Could it be TV Interference . . .” There was no indication of
any interference on the PA system but I wondered if the strong
UHF TV signal was simply swamping the wireless mic receiver.
Fortunately, the wireless mics were frequency agile, so it was
easy enough to prove, especially with a two mic/two receiver
system for an A:B comparison. I simply moved one of the mics
and its receiver to a frequency as far away as I could from where
it currently was, and bingo! The range suddenly increased to
what I was accustomed to while the other mic/receiver range
stayed stubbornly at about 10m!
I adjusted the second mic/receiver pair to another far-distant
frequency and was in business immediately.
No, I don’t know what frequency I adjusted it to; at the time,
I didn’t care – because it worked! I didn’t have any TV channel
listing with me nor did I have ’net access. I also knew I wasn’t
causing any TV intererence – there was a TV on in the same
room showing the World Cup! I might have been lucky but with
an event about to commence, that wasn’t my first concern. . . SC
siliconchip.com.au
August 2014 31
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