Yes; an easy way to record sound is a mike stuck up the headset earcup. I did that for years. Later I have used a direct connection to a spare headset socket. Various threads.
If one is talking about just one camera, I would mount it well somewhere and feed its extermal mike input directly from a headset socket, via the sort of adaptor I posted a circuit for. Then power it via USB power.
I have never seen a product which is 12V or 24V powered and simply starts recording. I posted it somewhere… I looked for such a device, for sound only, so it could be hidden. Currently I record all audio on flights away from base, for evidence “just in case”, but the setup is messy and gets in the way. I am sure it exists; possibly in the security business. The first issue with doing it with an off the shelf action cam is that these don’t support auto startup etc. You have to interact with them via the menu. A product which did all this would use a video camera module and some off the shelf computer.
Sharp used to make a mini disc recorder which was voice or sound activated . It doesn’t get activated by background ambient sound unless the engine suddenly coughs or something.
It takes a stereo mic to mini jack input and time and chapter data is recorded within the disc and can easily be synced up with the camera data
A feed can be taken from it either to headsets or another recorder or mixer.
I sync this up in my video edit software and then mix with other sounds eg those directly recorded in the camera after the edit along with any image manipulation and colour grading.
I have never seen a product which is 12V or 24V powered and simply starts recording.
Well, obviously, a CVR has to be done like that. But that thing won’t be cheap.
If I had time, I would build exactly such a product. Two actually. One a totally automatic audio recorder. One a totally automatic video camera. The 1st is trivial, once you have a board capable of digitising audio and writing an mp3. Probably a week’s work if you know how (I don’t; never done mp3, but the board I am working on now has the power of a single CPU of a Cray 1, a £5 chip). It would fit in a matchbox. The 2nd is a lot less trivial because the ex-camera-sensor data rate even of 50fps HD is pretty high, and to sell anything it has to be “4K” which IIRC runs with a ~700mbps rate off the sensor, and needs dedicated hardware.
Peter wrote:
I have never seen a product which is 12V or 24V powered and simply starts recording.
The cheap action cameras I use have this setting – like an automobile “dashcam” – they come on when they get USB power. Unfortunately the higher end cameras like the gopro do not seem to support this feature, which is a constant complaint on the gopro forums.
For this price (23euro), can’t go wrong. https://www.amazon.fr/Rollei-Actioncam-372-Résolution-Protection/dp/B078WYVZ9X/
Just search for “action camera” – if you want external sound recording, make sure it specifies that, or it’s just a built-in microphone which is pretty horrible.
In terms of cameras, the GoPro Hero 10 is probably the best on the market. It’s got a few issues with overheating, but if you’ve got relatively good circulation in the cockpit within 10 minutes and it’s somewhat shielded you’ll be okay. I’ve used a combination of GoPro Hero 7, 6 and 5 the last few years. They all have issues, but flying airways seems to have removed this – besides with COVID I tend to open all the vents now to help with ventilation.
In terms of audio setup, I’ve got a system in place where I have a cable that provides the ATC audio, it then runs into an attenuator as I’ve had massive issues with static and the audio being blown. This no longer happens, as I also turn down the input level on my H1N1. This was something that used to absolutely bug me.
I’ve also invested in some ND filters and am currently messing around with the settings on the GoPro 10 to find the perfect balance. I will be writing a blog eventually on all of this as the findings will help other aspirations.
Thanks. Do you record the intercom audio via cable with the gopro or using a dedicated recorder?
Snoopy wrote:
Thanks. Do you record the intercom audio via cable with the gopro or using a dedicated recorder?
Via the dedicated recorder now. I have tried via the camera with the usual recorders, however I had many issues with the attenuation. The setup I have now using the H1N1 as the recorder.
From Amazon – a Male Line-in to Male Microphone Attenuator cable (-25DB)
From Amazon – A Stereo Audio jack Adapter
Both ideally gold plated, reduces static to near zero. There’s some, but depends on how firm you have plugged the cables in. But it’s not that bad.
H1N1 allows power into it from a mains or Powerpack to allow long-term recording without using the batteries. I adjust the setting of the audio so it’s slightly below in DB so it’s not too blown.
