Hand held radio interference. A real issue!

World Media · Jun 30, 2015

I was filming a Red Stripe commercial in Jamaica last week (I'm a full time producer and director that uses the inspire as an amazing additional tool) with a reasonably sized film crew. As is normal I had equipped the film crew with hand held radios so that we can communicate on set and at locations.

Part of the commercial uses aerial scenes which we nailed with the use of the Inspire, I fly it with the help of a camera operator.
The scene were complex and required timing so we also had an assistant calling cues out to the talent on the radio.
We would set up shots, framing, exposure position and once set I would roll the camera on the inspire and call action.
The Inspire kept switching the record off. I would stop reset record to roll the camera call action and watch as the record button stopped record.
This happened for a day or so and I was getting pretty annoyed, then the assistant noticed it changed as he called action over the radio. A quick test confirmed that the radio was indeed causing this issue.

We moved the assistant about 15 feet away and all seems to be fine. So be aware that radios on that share this spectrum not only can interfere but DO interfere with the controller.

No doubt they could influence other attributes. so Always do a filed test.

The Inspire got us some shots that we just could not have got with a normal helicopter and worked flawlessly on set. Despite two previous flyaway crashes ( switching into atti mode close to an object before pilot could act).
Happy filming.

Scotflieger · Jun 30, 2015

World Media said:
I was filming a Red Stripe commercial in Jamaica last week (I'm a full time producer and director that uses the inspire as an amazing additional tool) with a reasonably sized film crew. As is normal I had equipped the film crew with hand held radios so that we can communicate on set and at locations.

Part of the commercial uses aerial scenes which we nailed with the use of the Inspire, I fly it with the help of a camera operator.
The scene were complex and required timing so we also had an assistant calling cues out to the talent on the radio.
We would set up shots, framing, exposure position and once set I would roll the camera on the inspire and call action.
The Inspire kept switching the record off. I would stop reset record to roll the camera call action and watch as the record button stopped record.
This happened for a day or so and I was getting pretty annoyed, then the assistant noticed it changed as he called action over the radio. A quick test confirmed that the radio was indeed causing this issue.

We moved the assistant about 15 feet away and all seems to be fine. So be aware that radios on that share this spectrum not only can interfere but DO interfere with the controller.

No doubt they could influence other attributes. so Always do a filed test.

The Inspire got us some shots that we just could not have got with a normal helicopter and worked flawlessly on set. Despite two previous flyaway crashes ( switching into atti mode close to an object before pilot could act).
Happy filming.

Great advice. Do you have or use a 2.4Hz handheld spectrum analyser? These are inexpensive (GBP 130) and allow you to identify any interference before it occurs.

mdomeny · Jun 30, 2015

i had the same issue and use an DECT system based intercom when possible which does not interfear.
my hanbdheld radios are grounded since they are also fairly strong... 5w at max... i think...

World Media · Jun 30, 2015

Scotflieger said:
Great advice. Do you have or use a 2.4Hz handheld spectrum analyser? These are inexpensive (GBP 130) and allow you to identify any interference before it occurs.

I don't have an analyzer, we also use radio based IFB systems ( which we use to talk to talent using almost invisible earpieces, they don't have the same effect but they are lower powered.

I really just thought it useful for other members so they are not standing there thinking WTF !

The aha moment was a relief.

Mazz · Jun 30, 2015

I must say I am a bit surprised to hear this as we also use hand held radios (four in total) at all of our sites and we have never seen a problem. I DID have the issue you are talking about but after some troubleshooting I found it was the SD card that was causing the "stop record" over and over. It was also very annoying for me until I figured it out. What kind of radios are you using?

Hooray BEER!

Mark C · Jun 30, 2015

Sounds an interesting job.
The spectrum analyser Scotflieger mentioned is worth getting for the 2.4 bandwidth. Take a reading then power on the inspire and see where your "spike" is on the readout.
Can I be nosy? Do you use the log profile when shooting or what setup does your editor prefer for output from the inspire?

Glad you worked out the issue with the radios.

World Media · Jun 30, 2015

We always use log profile, try to get the shutter speed as close to 1/60th second in 4k. We always shoot in 4k, that gives us the ability to crop in without losing any detail and still have full , clear 1080p.

The 2.4ghz spectrum is crowded, once we knew it was the ptr on the radio we were able to just move it away a few feet.

qbizzy · Jun 30, 2015

It was mentioned before. What is a good spectrum analyzer to get? Thanks!

Ivymantled · Jul 30, 2015

I was shooting footage of an SES (State Emergency Service) 4WD here in Australia a few weeks ago. As the Inspire approached the vehicle it suddenly headed steeply for the ground, props still spinning, and wouldn't respond to any controls. It was only about 20-30 feet altitude so there was no time to try RTH.

I later realized that this 4WD was bristling with antenna, had long range HF radio and who knows what other signaling and communication devices - and wondered whether it was pumping something out that blocked my signal.