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22 Nov 2023:  TR23 update: 10 reasons to attend

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DR/BR lesson from 9/11: have backup on backup on backup – and a Plan C.

“Inaction is not an option.  It’s only a disaster if you don’t plan for it”.

Installation of the WTC pole. What do you notice? See below!

During the last few weeks we’ve been reminded about the events of 11 September 2001, now known universally as “9/11”, when the World Trade Centre twin towers collapsed.

Over many trips to the US I had personally visited the towers a few times, doing all the obligatory tourist things.  That included heading to the roof on my first trip.  As a broadcaster, I marveled at the antenna system on the top of 1 WTC, the North Tower, extending a further 110m from the roof of a building already 420m above ground.

From 1978, most of New York’s broadcasters had FM and TV transmitters at 1 WTC.  Being the tallest spot in the city (indeed: tallest spot in the US and, for a while, the whole world) made it an ideal site for STLs and remote links; not just for TV but also for the many AM broadcasters who needed to bounce their program feed from a mid-town studio to mast sites along the Jersey shore and elsewhere.

All broadcasters operating at the site had several layers of hardware backup in the transmitter room.  Main and standby transmitters, parallel link paths, duplicated processors, signal and control path switching, supported by backup power generation and multiple antenna arrays.  As you would.  No chance of going off air.  Sure: despite all the equipment duplication, there was only one mast on the building, but that mast was comfortably engineered to take all the services.

It was such an obviously appropriate location that almost every broadcaster had cancelled their legacy leases at the Empire State Building (and the WTC had paid for many years of those leases in a sweetheart deal to get the broadcasters to relocate from Empire to WTC). So Empire State was mostly fallow, a 1930s building just capable of, but not required to do, a 2000s job.

Surprisingly, backup-on-backup didn’t include site diversity.  Nobody seemed to have considered whether the building itself needed a backup; building failure was not on anyone’s radar.  There was just no plan to deal with the bizarre consequence: what would happen if the North Tower suddenly was not there.

“Suddenly” turned out to be 102 minutes, the interval between when the plane hit the north tower, and when the building came down.  It was all over in seconds.

In that moment, all New York free-to-air broadcast transmission and link services stopped, silencing every service that was on, or went via, 1 WTC.  Hardwire backup links and other services – ISDN, landlines, phone lines, still worked until, at the end of an already unthinkably bad day, the Verizon Central Office (telephone exchange) went offline with the collapse of 7 WTC.

The extent of all these cause-and-effect relationships was extreme, and totally implausible.  And yet, it happened.

The 9/11 incident contains huge lessons for everyone in our industry.  So here’s a real gem:  at the Audio Engineering Society 115th convention held in New York on 10 October 2003, a group of broadcast engineers staged a panel titled “REBUILDING OF NEW YORK BROADCASTING” in which they took the audience through the events of the day, what broadcasters did to recover, and many of the lessons learned.

Base of the North Tower mast; it adds another 30 storeys to the building.

All the people on the panel, even the Public Broadcasters, are part of the big end of town: consider that their audience reach required them to be on the world’s tallest building.  But here’s the thing: what they say is incredibly relevant to small community broadcasters – even small stations running 10 watts – because the learnings from any recovery exercise are universal truths.

This is one of those talks that you really need to give a listen.  The full session ran 2.5 hours, and most of it was captured in this recording.

Hint: the file isn’t very big (20MB) and is easier to navigate if you download it – although you can listen to it just fine from the link above.  I have not yet been able to find the slides that accompanied the talks but I’ll reach out to AES over the coming week.  Meanwhile, there are  plenty of generic pictures on the web.

To help put things into perspective, check out Wikipedia articles on

and you can look at maps of the area.

Also, here’s a fascinating 1967 article about the Empire State Building antennas, written before the WTC was commissioned and fully 11 years before WTC North Tower came online.

Notes on the recording

Many times the location “Kearny” is mentioned;  that’s a suburb of New Jersey, just west of lower Manhattan, home to many AM transmitters and backup FM.  You can see the towers around 282 Polito Ave Lyndhurst NJ (Westinghouse site, four mast directional), and another two sites literally a few minutes walk away at 1427 Valley Brook Avenue  (look for towers on both sides of the road).  There’s another directional tower set about 200m south of Valley Brook.

At least two of the AM tower clusters have an FM array at the top of one mast. Wouldn’t that work?  Well… it looks really high and effective; a mid-band 1/4 wave AM mast is probably around 80m high.  That’s equivalent to putting an FM antenna on the top of a 25-storey building with nothing around to obstruct it.  Perfect, until you consider the wall of buildings that is Manhattan, and compare an 80m mast to the WTC pole, which was 110m high and had a 420m building underneath it.  Six times the height and right in the middle of the greater NYC/New Jersey area.

Listen carefully, and you will also hear occasional references to another tower in Alpine NJ, north west of New York City.  That’s the same location from which Edwin H Armstrong did the very first practical proof tests of FM broadcasting.

The Verizon Central Office next door to 7 WTC, and carrying significant amounts of broadcast traffic, was impacted when 7 WTC also came down.  Although much of the exchange appears to have been OK, cables and interconnects were affected.

7 WTC’s collapse was not from direct physical damage caused by the collapse of 1 WTC adjacent, but from fires started on multiple floors.  Some sources have attributed fires and the subsequent collapse to burning of diesel fuel, part of emergency power generation plant located quite low down.  The 7 WTC investigation suggested otherwise, and it’s very difficult to get diesel fuel to burn, but lack of water, bad sprinkler system design, and flying av-gas and flaming debris from the towers, created a perfect storm.  7 WTC is regarded as the only steel skyscraper ever to have collapsed due to fire.

What can you learn from the session?

Everyone on the panel was violently in agreement about some really valuable conclusions:

  • you can’t be too prepared;
  • you need a plan;
  • you need to test the plan;
  • you need to consider what’s the impact of being not on the air; and
  • your plan needs to cover eventualities that can’t possibly happen, because they can happen.

Enjoy, and comment in the Technorama Q&A.

Panel participants were:


  • David K. Bialik – Systems Engineering Consultant
  • Howard Price – ABC (the American corporation)


  • Joe Giardina – DSI
  • John Lyons – Durst Organization
  • Kevin Plumb – WABC, WPLJ
  • Steve Shultis – WNYC Radio
  • Thomas Silliman – ERI Inc.
Video of the attack

There are many programs and stories which have been told about the events of 9 September 2001.  None that I have seen comes anywhere near delivering the clarity and impact of “9/11: Life under attack”.  It is beautifully crafted, and tells the story through the eyes of people who had the presence of mind to hold a camera and keep it running.

At the time of writing, the program is available on ABC iView and also on YouTube.  It’s worth looking at both: they are two quite different edits all the way through to the end (tech note: you can sync the closing credits, and the overlay is identically timed, but the backgrounds are different).

Final word on backup

So did you notice the photo at the top of this article?  Who is this person who is standing at the top of a pole, over half a kilometre off the ground, leaning over into space while holding on with one hand, and with only a shirt and workboots as protection?  Wow.  You would not want to sneeze.  Even more bizarre?  The photo was shot from above.  Someone even more crazy was higher up, hanging in mid-air to take the pic.

DR/BR: Could your station recover from a cyber attack?

As an Australian TV network deals with a massive cyber-attack – one of the worst such corporate attacks to date, and still playing out as this article was being written – right now would be an excellent time to consider your station’s state of readiness.  Technorama President, John Maizels, reports.

The broadcast industry is a ripe target for cyber criminals.  Viruses, malware and bloatware are all nasty, annoying, and have repercussions.  But the worst possible form of attack is Ransomware.  Your station could be next.  This article is about how to avoid that, and might be the single most important advice that Technorama could give you this year.

Let me say at the outset: this is a lot of stuff to take in, and you could easily feel swamped by the time you get half way through.  Keep going.  If you only take one tip, and start with that, you’re ahead of the game.

The key questions are:  how prepared is your station for a cyber-threat, and how likely are you to be able to survive a direct attack?  Does your station have an active plan B?

To be really blunt: does everyone in your food-chain speak the language of business recovery and business continuity?

Many stations don’t have a plan

If you don’t have a solid strategy to handle a disaster, you’re not alone.  The trick is to start somewhere, and start now if you haven’t already.  In fact: start before you’re ready!

Step one is always to be informed, so this article asks the important questions, and suggests some beginning strategies.  Bigger answers will come later, but right now your best defence is to know that there is a challenge to be met, and what form that challenge might take.

To help you along, the Technorama brains-trust has mapped out some aspects to consider about cyber-threats and your station.

This article will be updated from time-to-time, as tips and hints come to light.  If you have a suggestion, or an experience to share, send an email to [email protected].   But let’s start with the obvious.

It’s about your mindset

The first step to readiness is to admit that a cyber-attack can happen.   Not only can it happen, but broadcasters are an obvious target, and your station is a broadcaster.

The outcome of an attack on a broadcaster is very visible, instills fear into the rest of the community, and the stakes are high enough that the demands can be high too.  Don’t assume that because your station is “community broadcasting” that the attack will be lessened, or that the attacker is ready to give you a discount.

The word “attack” might seem extreme, but that’s what it is so don’t mince words.  Consider that if it’s possible to attack a major television network with a cyber-security team in place, that it can happen to a community broadcaster.  It can happen to you.

It’s reasonable to assume that if you are hit, there will be consequences.  But don’t assume that your attacker is going to play fair.  Even if you pay the ransom, your files might not be unlocked and your systems might not be restored.  Money (or whatever the ransom is) might not even be the endgame.

Assume that if you haven’t thought about cyber-attack and recovery, any situation is going to be messy.

At the same time, Radio is much simpler to fix than Television. It’s not hard to get back on air, there are low-cost recovery methods, and you should not be broadcasting silence for very long at all.

How can you mitigate an attack?

Have the correct mindset: ensure that your colleagues, the board/committee, and anyone who has access to your gear knows that there is a real risk of virus, malware, and ransomware attack.

Then do everything you can to not be that target.

Plan to be attack-ready!

A key piece of advice is to have a plan in place, no matter how unlikely you think an attack might be.  Your station might be collateral damage in an attack intended for another organisation (eg: if you’re using the same software or systems).

Identify your critical assets, and know what the impact would be if those assets are compromised.  Then create an incident plan.  It doesn’t have to be complex or extremely detailed, but it does need to exist.  By having a response plan, you start from a position of preparedness and calm, which in turn will reduce fallout and promote confidence.

Assume that your station is a target.

If you’re a broadcaster, you are visible.  If you are visible, someone might decide your station is worth going after.

Create a reasonable “under attack” mindset and culture.  Ensure that everyone knows it’s not a matter of if, but when, and that every user of station facilities has a part in the protection strategy.

Encourage everyone to be aware of the consequences of a mis-click, an imported USB key, and the various attack vectors that cyber-criminals use.

Know your pressure-points

Look at your current environment, and be both realistic and brutal. Ask the question: do you have a single point of failure?  This is not just a technical question.  You can be attacked many ways, and your recovery depends on strategies with:

  • hardware/software/infrastructure: can you manage hardware and software in a way that ensures the problem isn’t made worse?
    • do you have spare hardware to cope with recovery?
    • is at least some of that hardware completely isolated from the live network?
  • people:  when the attack occurs, is there a defined list of people to call, and a sequence in which they will be called?  Who needs to know?  Who is capable of leading the recovery?  And if that’s one person, or someone who isn’t available: the station is exposed.
  • location:  is there a defined backup process for anything physical, and can you implement a recovery offsite?
  • protocol: does everyone understand that a cyber-attack is possible, and what to do if they are the first-noticer?

Security starts on the inside

Control who has access to your network, and which parts of the network they can access.  Control what resources can be reached by non-technical people.

Separate internet and on-air traffic.  At the very least, put your automation systems and internet access on separate VLANs, and ensure that the external internet can’t touch the automation system.

A smart way to manage networks is to construct the network with multiple NICs (network interface controllers) on critical machines. Create an internal and external network and ensure that network traffic can’t be cross coupled.

Ensure there is no reason for anyone to connect an external device directly to the broadcast network or a machine on the broadcast network.

Set clear IT policies.  Ensure everyone understands what is and isn’t a threat.

  • You can’t be infected with a virus from a WAV or MP3 file.  Audio files are audio, and not executable.
  • You can be infected with a viral carrier that is disguised as a WAV or MP3 file – and such a file won’t be playable audio.  If a file won’t play when dropped into an appliance player (eg: VLC) then maybe have a look more carefully.
  • You could easily be infected with a file that is trivially disguised.  For instance:
    • tune.mp3” is safe.  It can’t be executed.
    • tune.mp3 (lots of spaces) …exe” might not be noticed as an executable file, and is a threat

The Windows default, which is to hide file extensions of well known files, is one of the craziest decisions that Microsoft ever made.  You can change the defaults of file lists so that extensions are visible.  If the file is a .exe, you probably want to know.

The best policy is for your people not to download anything on-station unless it’s from a known, trusted, source.

Don’t go overboard

I’ve been in many stations where browsers, desktops, accesses and even office suites are so locked down that it’s hard to function.  That’s not desirable, and it’s not a good outcome.  Neither is it sensible (especially in small stations) to restrict access to only one person.  Balance your approach.  And before you tighten security, ensure that somewhere, in a trusted place, there is the password-containing envelope that can be ripped open in case of emergency.

Your aim is to secure the station, not cripple it and alienate all your volunteers.

To publicise or not?

If you do suffer an attack, there are two obvious PR strategies straight off the bat:  tell everyone, or keep it under wraps.  Your attacker would like nothing more than to have the work publicised – that’s how terrorism works, and if everyone else is fearful of an attack, the ransom toll can be steeper.  On the other hand, if your station is plunged into darkness, people will want to know what happened.

Turning a bug into a feature – being very open, even to the point of joking about it – is a powerful alternative.

The golden rule of PR is to have a strategy.  Everyone marches to the same tune.  So when you create your attack mitigation plan, ensure that a defined PR approach is part of what you do.  At least then you can relax on that aspect.

Prevention and Mitigation Basics

At the very least, you should do the basics.

  • Have a reputable anti-virus package installed on all your internet-accessible computers.
  • Have a backup strategy that involves taking backups once a week at the very least.  Daily incremental backups is an even better strategy.
  • Test your backups.  Backups are useless unless you know that a restore will work, and that you are comfortable with the restore procedure.  Backup and restore instructions should be written in a way that a non-technical person could follow, and be successful.
  • Have a complete set of backups stored offsite, and store these in a way that the backups are completely isolated from your active network – in fact, isolated from all other infrastructure.  If you have to bring a backup into play because your network is compromised:  don’t put your only backup on the compromised network!


If you’re hit: what are some considerations?  Most importantly: don’t panic. Don’t do anything that is likely to compromise whatever is still working – if the station is off air, you don’t want to make the situation worse by extending the off-air period while trying to shorten it.

Some simple tests:

  • check backups before restoring.  Are they clean?  Do they work?  Are you restoring the most recent appropriate version?
  • ensure that the machine to which you are restoring (and any machine that touches the backup) is clean before you attach backup media.  If you’re not sure: don’t do it.
  • Ensure you are restoring data, not programs.

Things you can do to protect your station

Have a Plan B.  That sounds so obvious, so ask: do you have one?  If the station is hit with a cyber attack, does everyone from the on-air presenter up know what to do next and who to call?

If you rely on automation, have a standby machine that is completely disconnected.  Even an old playlist is better than no playlist.  An old PC with a duplicate of your libraries is a good piece of insurance.

If you have a digital studio infrastructure, confirm that the console can’t be brought down by a cyber attack on another part of the network.  Consoles that rely on network attachment, and a Windows-based configuration controller, might be a point of risk.

Include appliances in your backup plan

Part if your recovery arsenal should be some tools that aren’t based on files, or connected IT. What does that mean?  Simple: be ready to play material from a source that can’t be compromised by a cyber attack. Appliances are your friend.

An appliance is a device which does exactly one job and can’t be tricked into being something else.  Examples of an audio appliance include CD player, DVD player, or a box which can play from a hard drive or USB stick.  Think in terms of old-school devices:  CD, cassette, vinyl, tape, and Edison cylinders are totally immune to computer viruses. Any of those will keep your station on the air.

If you have an analogue studio with CD players and turntables, you have massive protection already. It would be very hard for a cyber attack to knock you out completely.

In these days of substantial digitisation, your station might not have any of those playback devices in the studio.  So ask: if the network goes down, what can you use to deliver emergency program, and what is your strategy for program continuity?

Of all the devices available today, a DVD or BluRay player is the obvious choice as an emergency program source.  Cheap, easily available, and can’t be hacked.  Put one in the master racks for the rainy day.

Ideally, your emergency playout should bypass studios and all your other infrastructure.  Have cables and suitable interface available to connect the audio output from the appliance directly into your studio switcher.

Then ensure that you have a generic standby program sitting on a CD/DVD/BD, and that you have spare batteries for the remote control.

When all else fails

Don’t forget: your OB kit can double as an emergency studio.

Where next?

Technorama members, and everyone who has subscribed:  the Technorama Community Radio Tech Q&A Facebook Group is a great resource. It’s an excellent place to ask questions and get advice.

CBAA Awards: enter before 17 July

Although Technorama is running TR20V, we’re holding back on our Technologist Awards until much later in the year when we expect to run an in-person event.

Recognition of the work of technologists is vital, and you still have opportunities to be noticed.

With the challenges the sector has faced, we have seen amazing innovation and community connection and engagement. The CBAA Community Radio Awards celebrates stations achievements and their people. We want to celebrate their innovation, perseverance and community champions.

Entries are now open for more than 30 categories including: “Excellence in Technical Services” and “Excellence in Technical Innovation”. For more information about the award guidelines and how to enter online click here.

Who won the 2019 Excellence in Technical Innovation Awards?  Creative Automation Solution by Technorama member Alastair Ling from Edge Radio in Hobart, TAS.

Take a look at other previous winners here.

Tonight 31 March – Everyone Remote: Technical Distancing

Technorama Tuesday delivers the goods

When the universe sends lemons, it’s time to make lemonade.

Closing the station doors to keep volunteers safe creates interesting challenges… but there are solutions.   Even though everyone might be staying home and avoiding the station, there’s no medical rule that says your station has to sound sick.

On Tuesday 31 March Tim Borgas (SACBA) offers ideas and tips to help your station’s operation as healthy as you are.  Think tech, programming, gear, remote operation, and how to sound GOOOOOODDDD during the COVID-19 pandemic.
Register here and join from home!   You don’t have to be a tech for this one;  everybody is welcome and will take away a few good thoughts.

Did you miss a webinar?

You can catch previous Technorama Tuesdays – including last months excellent session on documenting your station.
Just follow this link to get access to whole series.

Technorama TR20

As you might have guessed, the COVID-19 pandemic completely kaiboshed our plans to run TR20 in Toowoomba in late May.   We waited as long as we could to make a decision, until events overtook us and force our hand.

But there’s good news:  we’ll be back as soon as we’re able.  And our lemonade machine is working overtime on the Plan B, because all good technologists have a Plan B.   Watch this space.

Info and tips on COVID-19

We’ve been busy creating info to help you deal with the nasties, and doing our best to cut through the fog with real science.   Check the Technorama website for useful stories on not destroying microphones with Glen 20, how to deal with pop shields, why barrier filters might be the wrong idea, what the virus really does, and a neat simulator to help you and your station mates understand why social distancing is a great option.   Check out  COVID-19: helpful support information and save a few lives.

For the team,

John Maizels
President, Technorama Incorporated
[email protected]

PS:  tell your friends and help get the Technorama messages out!

COVID-19: helpful support information

One of the toughest questions you should ask when dealing with the COVID-19 pandemic is: “how do I know this information is right”.  Over the last two weeks, we’ve seen convergence of information, and development of authoritative sources.   And we’ve policed our own discussions to try to ensure the best possible info.

We’re here to help

The Technorama Facebook Q&A group has been described as “the most useful source of advice for getting ready to deal with working to prevent the spread of the Corona virus.”  We try.

Q&A is a “closed group”, which is a standard Facebook mechanism intended to improve signal-to-noise ratio.  We ask a few questions of applicants to confirm that they have an affinity with Community Broadcasting (as described in the policy page).  Anyone who answers the questions is admitted very quickly, and we are monitoring the group to ensure that.

Medical information?

Your first point of contact for medical questions related to COVID-19 could be:

All of these organisations represent best effort to provide good information.  Even where mistakes or inconsistencies occur, they are all heavily internally reviewed and subject to feedback.

Technorama cannot provide medical advice (and we don’t) but we can point you at information sources which appear, to us, to have a good basis in science.   It’s also in our remit to give you access to the best tools that we can find.

Other useful links

In the spirit of that, here are some additional links that we believe are truly useful:

This lovingly crafted video shows how a well-researched creative team can work miracles.  In 8 minutes it explains the science behind the pandemic, how the SARS-NCOV-2 virus works, and why all the stuff we’re being told is important.  After watching the video, you should be able to explain why isolation and handwashing is so effective and necessary.

Melting Asphalt created a simulation tool to help you visualise how a pandemic occurs and propagates.  What’s fascinating is that it provides knobs that you can adjust to change the way the outbreak moves.  There’s even a challenge to see if you can quickly find a balance where the disease stops.  The model steps you through many stages, and you can reset, start again, and step through as often as you like.





Pantyhose popfilters and COVID-19: not so good

Keeping our studio safe
Can you protect your microphones, and the people who use them, with a filter in front of the pop shield?   The answer is maybe, but maybe not.   Maybe very not.

As technologists, we create danger if we recommend protection measures which seem OK, but aren’t.  In these times, we can’t risk creating a false sense of security.   Zero tolerance.

Here’s some science to help you think about and explain why care is needed with pop filters.
Virus protection and microphones
Earlier tonight I saw a suggestion that studio hygiene could be helped if a pantyhose-style shield was put in front of a mic, with the pantyhose material being changed and/or washed regularly.  That seems like a really good and practical suggestion, and it’s certainly well-meant.  But does it do what you want?  Engineering analysis suggests that it’s actually a really BAAAAD idea if what you want to do is stop a potential COVID-19 vector.

It’s all about the holes

Simply, the pantyhose shield idea puts a barrier between a mouth and the microphone, and relies on the barrier to stop germs from getting through.   Can it work?
To protect the mic from exhaled breath and viruses, a washable pantyhose filter (or any intermediate filter, reusable or disposable) **MUST** have a pore size smaller than the virus. If the pore size is bigger than the virus, then a virus which hits the filter can go through. That’s sort of stating the obvious, but it’s the starting point and very important.

The soak test

Try this.  Take a pantyhose-style pop filter. Hold your hand on the far side of the pantyhose and spray water from the near side.  Pretend the water spray is your mouth and you’re talking realistically, so you’ll need to spray the water at plosive or sneeze velocity.  Spray-spray.  Does your hand get damp? If it does: the filter has allowed water droplets through and those droplets could carry hundreds of thousands of viruses.
Because pantyhose is relatively coarse, breath droplets possibly containing a virus could relatively easily squeeze through the pantyhose filter and hit the foam filter that covers the mic. They stay there. When you change or replace the pantyhose filter, and the next person breathes in, there’s a finite possibility that the virus gets sucked off the foam and back through the pantyhose filter.

It could work

Definitely.  A filter *can* do the job of stopping bug transmission: the filter pore size just has to be smaller than the virus you want to block.  Another way:  if the hole is too small for the thingy, it wedges in and can’t pass.
Back-of-envelope maths
How small does the pore have to be to stop a virus? The coronavirus is given as about 120-125nm in diameter (by the way, that’s big for a virus.  There are some MUCH smaller, down to 5nm).  A filter pore size of 90nm would be prudent and would do the job.
It’s not easy to find info on pop-shield pore sizes – somewhat esoteric information, but one patent application reviewed for a porous solid pop-shield (as good as they get) had a median pore size of 10-60 microns, which is really small, and smaller than foam.  To get a reasonable frequency response, the pore size needs to be more like 100 microns
But consider that 120nm, the approximate size of the SARS-CoV-2 coronavirus, converts to 0.12 microns. In other words, really small pop shield pores are, at smallest, still one hundred times bigger than the virus and a practical shield that sounds OK would be ONE THOUSAND TIMES BIGGER than the virus.   A lot of stuff could get through the pop shield holes.   Quick maths check:  a sphere that fits through a 100 micron hole could contain 640,000 coronaviruses.  That’s a 100 micron water drop which is 0.1mm.   Not all of the critters will get through but, statistically, it’s possible that some will.  This is a numbers game in which the best defence is to reduce the statistical likelihood of inhaling the bug.


What’s the pore size for pantyhose?  Huge.   This type of filter has really, REALLY big holes; elephantine by comparison with bugs and water drops. To be blunt: pantyhose stops pretty much nothing that you need to stop, except plosives. The bottom line is that a pantyhose-style pop filter sounds good and is very effective in the intended role of stopping pops, but potentially does nothing useful as a virus barrier.
And if you’re making other connections, filter pore-size analysis does at least at least tally with the advice from those medical experts who say that facemasks don’t help the healthy.

So the answer is

Best wash your foam popshield in soapy water, which really does nobble the virus and provide good protection against retransmission.
Last update 2020-03-19 00:15

COVID-19 and your station

Things you can do to reduce risk

There are some quite simple and inexpensive strategies and tactics that you can adopt to reduce the chances of having a COVID-19 outbreak at your station.

The most important single thing you can do is be vigilant.  None of these suggestions provides a guarantee, but they will all help.  One of them might make the difference between being able to remain live and having to shut the doors.


  1. Advise presenters to come to the station only to do their shift
  2. Don’t allow anyone to come in if they feel sick.
  3. Emphasise the need for everyone to sign in in case they have to be tracked or notified later
  4. Do interviews by phone or telepresence, rather than with live guests
    • Skype, Zoom, GoToMeeting, Webex, Messenger, and a number of other tools provide audio that is better quality than the phone.
    • Telepresence tools allow you to combine multiple guests into a single feed, and that takes pressure off the number of channels your desk needs
    • Check with your techs to see if those tools can be made available
  5. Make mission-critical areas of the station off limits to everyone but specific persons, such as:
    • office:  restrict to staff
    • tech area:  restrict to tech (you do that anyway, yes?)
  6. Switch studios between programs, and use prep time to do a spot clean of the work surfaces
  7. Provide handwipes, soap, hand disinfectant and lots of water
  8. Empty bins frequently
  9. Put up lots of signs to remind people of some science:
    • soap and detergent will render the virus unable to work, and here’s why.  The virus isn’t killed, but the surfactant will neutralise it and then it eventually “dies”
    • gloves will protect your skin, but stuff sticks to gloves too and can be transferred into your body if you touch your face with the glove
    • face masks probably don’t help unless the pores are smaller than a virus
  10. Point people to the Technorama website and particularly the resources tab
  11. Order additional pop shields, allocate one per presenter, and
    1. make the presenter responsible for washing it, OR
    2. institute a policy of washing pop shields within the station
  12. Consider using disposable covers, but remember that overlay materials might not work in the way you hope:
    • a virus is microscopic, and can easily penetrate a filter that might stop bacteria.  The filter pore size must be smaller than a virus or it’s not going to achieve much
    • you don’t want a virus to be trapped where you can’t see it, lying in wait behind the cover to be transferred back to you or someone else.
  13. Use isopropyl alcohol and other antiseptics to wipe down surfaces and electronics (including the panel).
  14. if you are using a liquid antiseptic, either spray it onto a cloth and apply it from the cloth, or pour liquid into a small container (like a bottle cap) so that you don’t pollute the supply.  Microfibre cloths are perfect for cleaning.   Plus they are reusable:  just wash them in detergent.
  15. Don’t confuse antiseptics with antibacterials or disinfectants.  They are different three different substances with different properties
  16. Don’t use disinfectants on equipment, people, or anything through which a person might breathe unless the disinfectant is explicitly certified safe for breathing.  Even then it’s not a good idea, because people have allergies and your favourite disinfectant might be one of them
  17. Wash fader knobs occasionally with soap and water.  An electric toothbrush (or even a manual toothbrush) is a good tool to use.   BUT: don’t pull knobs off unless you are absolutely sure that you know how, and have been cleared to do so by your tech.
  18. Reposition OB gear outside the station and test it to ensure that you could use it to stay on-air if the station has to be quarantined
  19. Have a fully tested copy of your automation system (hardware, software, and library) located off-site.
  20. Confirm that you can do voice-tracking and remote schedule management so that programs can be created and changed from offsite
  21. Use your station’s social media groups to stay in contact with other presenters, but remember that if the group is open your discussion could be read by people who will misinterpret the messaging.

99.9% fatal to germs; 100% fatal to microphones!

Technorama members are asking (and being asked) many technology questions related to the COVID-19 pandemic, like:

  • Can COVID-19 be passed on through a pop-shield, or by touching a console?
  • What do you need to know to stay safe in a radio studio, and should you spray everything in sight with disinfectant?
  • What is the risk if your shift follows a presenter who knew someone who had met a nurse who had contact with a mate who was in the same room as a COVID-19-positive human?

We’ve covered these and many related topics in the Technorama Q&A Facebook group in this thread and others.   But if you’re not on Facebook, or if you missed the discussion, then read on and stay for the ride.

Full disclosure:  John Maizels, the author of this piece, is a senior technologist and broadcaster who has done the usual rounds of getting sick and well again.  He is President of Technorama, and has cleaned many studios.  He also reads a lot and asks many questions.  However he isn’t a medical practitioner, and is not a virologist. He is completely fascinated by the science, and is trying to help his colleagues wade through information and disinformation.

The information that follows addresses some technology issues and is presented in the interests of your health and well-being as a broadcaster.  The text might contain errors, so feel free to fact-check our fact-checking.   Note that the background science has been researched to the best of the author’s ability, and the recommendations are based on good practice from the engineering point of view.  E&OE.  Views expressed here are not necessarily those of Technorama.  This article contains a number of weblinks, including references to Wikipedia articles.  These links are included for reference and to be helpful, but the author makes no warranties about the accuracy of information in the links (which could change at any time).

Now that we’ve dealt with caveats, on with the meat.

Executive summary – the management one-pager

This is what’s going on:

  • the SARS-CoV-2 Coronavirus is believed to be passed from host to host via droplets of water.
  • a virus exists and hangs around best in a cooler, drier environment.  Equipment surfaces can be ideal.
  • the virus cannot multiply outside the body
  • inside the body, a virus multiplies by invading host cells and replicating, and it does that until the process is interrupted by antibodies, or until the host cell (or the host) dies.   Anything that kills the virus while it’s active in a host cell also kills the host cell – that’s one of the challenges of virology
  • the virus action can be disrupted easily: soap, detergents, and human antibodies mess up the lipid layer that coats the virus and then it can’t bind with a cell
  • a radio studio, and in particular a foam pop shield, isn’t necessarily a germ factory, but it could be
  • there are many treatments which will kill a virus outside the body, but many of those treatments aren’t friendly to equipment
  • more specifically there are treatments which will kill bugs in a pop-shield, but some of those treatments are unhelpful to the microphone and some may also harm you
  • sterilisation substances which identify as “antiseptic” are your best bet generally for germ elimination
  • detergents and soaps very specifically render coronavirus unharmful
  • washing, in soapy water, anything that might contact a coronavirus is a good thing.
  • Start with hands, because hands are easy to wash.  Wash properly and often.

You do need to know this: what is a virus and how does it work?

COVID-19, the disease which has been classified as a global pandemic, is caused by the action of the SARS-CoV-2 virus, a bug so small that it can only be seen with an electron microscope.

COVID-19 is scary because it’s new, we have no natural or herd immunity, and it lurks in dark corners.   Most people don’t really understand what a virus is (or they wouldn’t ask for an antibiotic to treat it), which adds to the likelihood that it won’t be treated correctly.

A virus is not a living organism, and it can’t replicate outside a host cell no matter how much food is around.   So what is it?   In general, a virus consists of an RNA strand, wrapped in protein.  Some viruses, such as the SARS virus, also have an outer layer of lipid, an organic molecule which is oily or waxy.  In the case of the SARS virus, the lipid layer binds with a host cell and allows the virus to invade the cell.  There are other features of the SARS-CoV-2 virus which help it to get to the bottom of the lungs, which is not good for us.

Despite the simplicity of its makeup, a virus works cleverly and elegantly.   Once it’s inside the host cell, it tricks the cell into creating many, many replicas of the viral matter, and the viral matter then buds out of the cell.  The cell dies, and the expanded amount of virus matter moves on to try to bind with more cells.  Unchecked, the virus takes over all the cells nearby.

The SARS-CoV-2 virus attacks the inside of the lungs, which is why the disease is characterised by coughing, shortness of breath, and general disruption of the process which gets oxygen into the bloodstream.   The lungs start to fill full of garbage, and become much less effective.

The body’s natural defence for viral attack is an antibody, a protein which can stick to the surface of a virus.  Antibodies are very specific, and each antibody can only attack one type of antigen (a virus or bacterium).   In the case of the SARS virus, the antibody interferes with the lipid layer of the virus, rendering it unable to attack a cell.  However because the SARS-CoV-2 virus is new (“novel”) humans have no existing immunity, and the body has to start from scratch when it’s infected.  That’s not good.

You can read more about the viral cycle here – all viruses work more or less like that description.

Outside a cell, the virus sits inert, unable to do anything except wait for an opportunity to transfer into a host.  A virus is pretty much just protein and nucleic acid. It has no will, and no drive; its behaviour is opportunistic.  If you break the cycle, you eliminate the virus and you stay safe.

Transmission of the coronavirus family (the “vector”) is through droplets of moisture, which must be inhaled, or otherwise passed via a damp passage into the body.

Getting out is easy:  all the stuff collecting in the lungs causes the body to trigger coughing as the way of getting rid of it.   When you cough, droplets of water (containing the virus) come out of your mouth at speed, and that’s a major vector for spreading the disease.  Getting a virus into the next body is a bit more tricky, but your mouth, nose and eyes provide a suitable passage.

That’s where the cycle must be broken and that’s why PR campaigns are focused on how you can prevent the virus from getting into the body in the first place.

What kills the coronavirus outside the body?

Basically any antiseptic will do the trick.   An antiseptic is a germ-killing substance, such as a pure alcohol, that can be applied to the skin, and is non-toxic.   Very important, that.

But what about…

Two other substances are often confused with antiseptics.

1. an antibiotic is a substance that slows or kills bacteria.  Antibiotics have no effect on a virus because a virus isn’t actually alive.

2. a disinfectant is a substance that kills germs and parasites.  Disinfectants can cover a lot of ground, and kill a lot of nasty bugs, but they can also kill you.

And here’s a warning:  anything will kill you if you have enough of it.  Drinking too much water can be fatal, and overexposure to the treatment is a potential problem with antiseptics, antibiotics, and disinfectants.  What’s important here is that disinfectants are more likely (than than antiseptics or antibiotics) to be dangerous or even deadly to humans if the concentration of the disinfectant is high enough.  Even in lower concentrations a disinfectant can cause annoying symptoms, especially if it’s breathed in or if you have an allergy to one of the active ingredients.

The reminder:  antibiotics do nothing for a virus.  They will help fight a secondary bacterial infection if you actually have one, but over-use of antibiotics when there’s no need (“Doctor, you must give me something”) is reducing their effectiveness.  That’s a different story for another day.   Just don’t use antibiotics unless there’s a need.

And now the million dollar question:  how dangerous is a broadcast studio?

Normally not very dangerous at all, unless you’re the sort of person who routinely spills coffee into consoles, pokes pens into power points, or annoys the Chief Engineer.  But a less-than-spotless studio can harbour bugs.

The SARS virus might live on a surface for a while.  It might only be a day or two, but previous studies have found human coronaviruses could theoretically last on a surface at room temperature for up to nine days – especially if humidity, temperature and cleanliness are low.   Viruses survive on hard shiny surfaces longer than on soft ones.  It is possible for the virus to be transferred from hard or soft surfaces back into the body if you touch the surface and then touch your mouth, nose or eyes.   Gloves won’t help because the surface of the glove itself can be a carrier.  And studios are places where people typically are in close proximity to each other, which just increases the chances of passing on the bug.

A pop shield (and, indeed, any type of microphone windshield) might be a pass-on vector or it might not.  The likelihood of picking up any virus from a foam shield depends on how damp the shield remains, how close you work to the mic, whether you are contacting it with your mouth or hands,  whether you’ve created a way for viral matter to jump into your body, and whether the shield contains a virus in the first place (and in sufficient concentration to trigger an infection).

The best protection is cleanliness.

What works to sterilise a studio?

Consoles, hardware and furniture can be wiped with a disinfectant or an antiseptic.  Which treatment you use depends on the thing you’re trying to clean, and the nature of the substance.  In general, disinfectants contain all kinds of stuff that isn’t friendly to hardware.  On the other hand antiseptics tend to be relatively benign to hardware and people.  Start with antiseptics if you have any control over what’s used.

Isopropyl alcohol is a good antiseptic, especially when it is pure (beware of stuff labelled “rubbing alcohol”, which might contain other stuff friendly to skin but not equipment, and is probably only 70% alcohol).

Those packet alcohol wipes used for sterilising skin prior to an injection contain isopropyl alcohol and are a good – if expensive – way to clean and sterilise equipment (consoles, CD players, in-ear-monitors, metals and most plastics).

Methylated spirits is ethanol alcohol that is denatured, which means it contains stuff that makes it unpalatable, and indeed unsafe, to drink.  Meths is OK on most equipment, but it’s not as pure as isopropyl alcohol and might leave a residue.

And pop shields?

The absolute best treatment for a foam pop shield is to wash it in warm soapy water.  Rinse thoroughly and then dry – slowly.

That process works because soap, like a detergent, is a surfactant, and a surfactant interferes with the lipid layer of the SARS virus.  Without the lipid layer, the virus can’t invade a cell.

Aha, you say.  So THAT’s why the constant advice is “wash your hands”.  Yes it is.  Soap and detergent is a great weapon in the fight against COVID-19.  Washing your hands is excellent.

Washing a pop shield in soapy water is mechanically acceptable, and won’t harm the pop shield, but it will do nasty things to the virus.   Plus the pop shield might come out smelling nice and clean.

What about Glen 20 and other spray disinfectants?

The author personally knows of cases where a strongish disinfectant has been sprayed around a studio and into a pop shield.

There are two reasons that spraying disinfectant everywhere is not a good idea.  Disinfectants can do nasty things to plastics and foams.  Read the label.   If it says “don’t inhale” (and the label for Glen 20 says that) then maybe you’ve been given good advice: don’t inhale.  So don’t spray where you’ll inhale.   And, in general, it takes a lower concentration of disinfectant to annoy your body than a similar amount of alcohol.

If you must use spray on a pop shield, then maybe try “Sterisol”, or a similar substance that is intended for putting on items that you might then put in or near your mouth.  You could also try spray-bottle isopropyl alcohol.

Whatever you use, the pop-shield does not need to be soaked in spray for the sterilisation  to work.  And the foam should be very dry before the next presenter (or you) attempts to use it, so that you’re not inhaling stuff that won’t help your lungs.

Finally, and this isn’t as obvious to some people as you might think:  get the microphone out of the way before any treatment.  Wiping a microphone down with an alcohol wipe is likely to be safe, but don’t spray a microphone, and don’t spray a pop shield that’s still on a microphone.   Your “kills 99.9% of germs” spray product may well kill 100% of microphones, and nobody will love you for that.

Anything else?

Yes – UV radiation kills viruses.  Whether that’s useful information in your situation is beyond this article, but it’s included for completeness, and no information is available to suggest that UV irradiation is going to be better than exposure to soap.

A really good approach:  lots of pop shields and soap.

If you want to promote best hygiene in a studio, issue every presenter with their own pop shield.   Pop shields aren’t expensive, around AUD$20 for a good one, and that’s way cheaper than getting sick.  It should be the presenter’s responsibility to wash – and dry – the pop shield between sessions.

Any pop shield is better than no pop shield, especially if the aim is to provide your presenters with a personal barrier.  But some cheapo pop shields don’t actually do much to anti-pop, are made of foam which will disintegrate after longer term exposure to air, and react very badly to antiseptics and disinfectants.

A good choice of pop shield is the Rode WS2.  This foam shield fits the Rode Procaster, Podcaster and Broadcaster mikes.  It will most likely fit an Electrovoice RE20, the Sennheiser MD-421, and any number of classic 1″ condenser mikes (such as the Rode NT1/NT2, Neumann U87, Audio Technica AT2020, and AKG C414).  Rode also make a smaller pop shield, the WS3, which fits the Rode M3 and might also fit the AKG C1000 and similar medium barrel mikes.   We haven’t tested the shields on all those mics, so your mileage may vary.

Where do you get pop shields at the right price?

A list of suppliers will be added in the next 24 hours.  Technorama spoke to Rode late last week, and under normal circumstances we might have been seeking a direct discount deal for members.  However the COVID-19 pandemic is just too big for us to take that on.

And there’s another reason for you to make your own purchase:  this is the right time for you to approach your local dealer and get your supply from an existing retail or professional outlet.   Every outlet needs business right now, and buying locally is the right thing to do.  And feel free to say “Technorama sent us”.

Who sells pop shields?

This incomplete list was assembled from contacts in the industry; it can’t possibly be complete, but it’s a start.  Information provided here is in no particular order, and no recommendation should be inferred – we are simply providing some contact points as a service to members and readers.

If you have a favourite pop shield dealer who should be on this list (and has stock and/or can supply product in quantity) please drop a line to john AT technorama org au (you know the deal with addresses) and he will update the list.

Is any pop shield better than any other?  Marginally, but it’s way beyond our capacity right now to test or recommend.  Brand-name pop shields are likely to last better, and will most likely be made of a foam that is both more robust and actually does the job it’s supposed to do: stop pops.  Not every piece of foam works or sounds the same, and you will find cheap pop shields which muffle the audio and still don’t stop popping.

We do know that Rode has a fine product, it tests well, the company is Australian and worthy of support, and the market price per unit is around $20 or lower.   Those are all good recommendation points.

Identified resellers

Who Where
Factory Sound Melbourne
Videocraft Sydney, Melbourne
Turramurra Music Sydney
Derringers Adelaide
Pro AV Adelaide
VideoPro Brisbane
Brisbane Sound Group Brisbane
Store DJ/Mannys Music Sydney, Melbourne, Brisbane, Perth
DJ City Sydney, Melbourne, Brisbane
Bandland Toowoomba
Lemac Sydney, Brisbane, Melbourne
Carlingford Music Sydney
eBay Global


Article last update:  12:30  2020-03-17

Breaking news: TR20 location and Guest of Honour announced

Technorama TR20 will be held at the Oaks Toowoomba Hotel, a boutique location with over 130 guest rooms and a large modern conference centre.   Although the complex doesn’t open until 18 April, we’ve visited it several times – it’s exciting, and the rooms are more impressive than at any TR conference location to date.

You can check out the room details on the Oaks website, but don’t book yet:  there are plenty of rooms and we will have a special code available to get you a special TR20 rate.

Today we’re also announcing that the TR20 Special Guest of Honour is Stephen Dunifer, founder of Free Radio Berkeley.  Stephen led the establishment of the micropower FM movement in the US.   Today, Stephen Dunifer designs and builds FM transmitters aimed at the low-power market (under 600W – the US has a different idea of what “low power” and “micro power” means), and regularly runs classes to teach communities how to get on air.  If you’d like a taste of his products, check here.

Registration for TR20 has been held back, pending the final negotiations for our venue.   We expect online TR20 registration to open this weekend, and if you’re on our mailing list we’ll send you an email as soon as registration is unleashed.

Not sure if you’re on the mailing list?   If you’re a member, then you are.  If you’re not a member, don’t forget that members get a $15 discount on registration and you can join online.  But if that doesn’t suit, just fill in the form on the home-page to be added to our general information list.


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