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noexcessivecranking
19th Feb 2007, 05:04
Disclaimer: I am not an electronics person.

Has anyone rigged up a recording device that effectively picks up anything that goes to the headset earphones (ie. ICS as well as radio transmissions as well as all background radio chatter)?

I'm thinking specifically of using this with a NATO plug, so instructions for doing it with a fixed-wing-type split lead thingy wouldn't help me (ref disclaimer above).

I'm asking for tips, or "good God don't even think about it" comments, because I've heard you can cause problems by using the wrong input signal to a "standard" microphone input on, say, an MP3 recording device, or dictaphone type thing, and subsequently fry the bugger.

Is this making sense to anyone? :)

idle stop
19th Feb 2007, 06:18
For test flying purposes I use an external mic on my Panasonic dictaphone. If you get the sort of mic which attaches to a telephone (sticks on with a suction cup) this is just the job. It can be placed inside the ear-cup of a headset or flying helmet and is quite comfortable to use. However, it will pick up some extraneous noise. But it will always work, whatever the system impedence of the aircraft being flown.

Flying Bull
19th Feb 2007, 07:51
Hi noexcessivecranking,

Handy with kabel free-speaking-unit works.
The microphones are so smal by now and the cabel so thin, that it is quite easy, to place the mic into the headset.
With a litte fudling, you get the earphones and the mic so inside, that you don't have interferences, then you can actually make/receive phonecalls (depending on the altitude you're flying ;-))

Greetings
"Flying Bull"

noexcessivecranking
19th Feb 2007, 08:05
In your experience, is the amount of engine noise bearable? Could you use the recording as a training aid?

Ascend Charlie
19th Feb 2007, 08:26
I used a little Panasonic cassette recorder which has a vox setting, plus a little mic on a long cord.

Put the mic inside the earcup, put the recorder on your belt, and adjust the vox sensitivity until it only breaks when you press the intercom button or the radio receives something. The recorder stops after 10 secs of silence.

The end result is a faithful record of all intercom and radio comms, without the huge gaps of silence that come in real time. great for giving the cassette to the student after his flight, to listen in the car on the way home. Amazing how many times they hear me telling them to do something before they actually do it.

Flying Bull
19th Feb 2007, 16:42
Hi noexcessivecranking,

have a tight sitting headset.
Going to fly this or one of the next nights - if weather permits and we're needed ;-) (otherwise playing cards ;-))
I'm doing a recording with my SE-Handy and send you a personal mail, where you can find it to download.

Greetings "Flying Bull"

TwinHueyMan
20th Feb 2007, 08:05
I did the in-the-earcup thing for a while, however found that whatever I said would be picked up much louder due to my jaw making so damn much noise (similar to those fancy bone microphones firefighters use). Now I use an extra Davie Clark with a Lav (lapel) mic put inside, the cups taped together. Mic goes to a cheap-o voice recorder's mic plug. Picks up just enough ambient engine noise so you can hear power changes, ETL vibrato, etc and everyone's speech volume is equal. We have plenty of ICS plugs on our helicopter, though a splitter could be fashioned by a smart electrician if you're running low on plug ins.

I've also used the in-the-extra-headset bit with a wireless transmitter for video outside the helicopter, such as video for classes on hoisting. Makes it a lot easier than recording it on a voice recorder, then using some form of post processing to mix it.

-Mike

noexcessivecranking
20th Feb 2007, 09:36
Thanks Mike, great value - that sounds like a winner.

whosthatS76pilot
20th Feb 2007, 20:08
Buy a digital recorder (about $50) and wire a jack from your headset earpiece. I used a 3.5mm female jack and simply plug a 3.5mm audio lead from the headset to the recorder. Records perfectly all intercom/radio. You can also play MP3 etc back through it for music. Works a treat.

noexcessivecranking
21st Feb 2007, 07:47
Sorry, I don't understand. Do you mean it's possible to connect the microphone input wires to the headset earpiece wires? I would have thought this to be the perfect recipe for frying your digital recorder. And where can you get a digital recorder for $50? The cheapest I've found is about $90 for anything more than about 30 minutes of recording time.

whosthatS76pilot
23rd Feb 2007, 01:36
Well it doesn't fry mine! I bought the digital recorder in the US for about US$40 and can record about 3.5 hours. You can connect it to any recorder though, most accept a 3.5 mm standard jack.

Flying Bull
23rd Feb 2007, 09:36
Hi all,

for recording - some searching at ebay for mp3 player and recording (I did it with the german words ;-) ) and you get for 45€ including sending (in Germany) a device, capable of recording up to 280 hrs.

http://cgi.ebay.de/1-8-LCD-2-GB-2GB-MP3-MP4-Video-Movie-Player-PMP-sch-M_W0QQitemZ280085129951QQihZ018QQcategoryZ8267QQrdZ1QQcmdZVi ewItem

Some other excamples with less recording time
http://cgi.ebay.de/USB-MP3-Player-Stick-Diktiergeraet-1024-MB-M-1-GB_W0QQitemZ330089798450QQihZ014QQcategoryZ8267QQrdZ1QQcmdZV iewItem
36 € with 1GB Memory

or 26 € with 512 MB memory.
http://cgi.ebay.de/ws/eBayISAPI.dll?ViewItem&item=330089798579&ssPageName=MERC_VI_RUPX_Pr4_PcY_BIN_Stores_IT&refitem=330089798450&itemcount=4&refwidgetloc=active_view_item&usedrule1=UpSell_LogicX&refwidgettype=cross_promot_widget

Just put the mp3 player in record-modus and put it in some soft foam plastik in an extra headset, hold together with tape or rubber band and you can record the whole flight.

It also works with the microphone of a cabel headset from a mobile phone (as noexcessivecranking should know by now), but there you get (depending of the phone) only amr-records, which you have to convert to mp3, to use them with the computer (or get a programm, playing amr)

Greetings Flying Bull