Faq?

[do re meep meep]

I'm looking for a way to place a wireless microphone in a backyard birdbox to monitor and record on a computer in the house. I'm so ignorant that I don't know what questions to ask. Is there a FAQ or a tutorial on the net that I can read?

[ermine]

How far is your bird box from the house? Is power available locally?

The general problem with using wireless in sound recording is it tends to be one-way, so you need to set up recording levels at the remote location so that things don't go over the top or are so low as to be hissy. You can probably manage this in this app with a bit of trial-and-error. Plus you still have to switch the batteries at the remote site, regularly if you are running 24/7.

If it's not too far then try something like a wireless webcam (http://www.amazon.com/megalistandiston/dp/B000067JZF)

if you have ambitions of quality try something like a radiomic system (http://www.musiciansfriend.com/product/Sennheiser-freePORT-Wireless-Instrument-Set?sku=270855)

These guys (http://www.eco-watch.com/filmmakers/wildlifesurveillanceequipment.htm) make some of the stuff used by TV companies for nestbox cams - I've seen their stuff at shows but it's pricey.

and if your ambitions are lower than you can consider some of the spy microphone things, mini FM transmitters etc. Google will be your friend there - search on spy radio bug. Divide all claimed radio ranges by three to get some semblance of reality

Wireless is a nice idea but the powering and control issues can make it a pain. Cable is cheap... Recording on your PC can be done using the free Audacity (http://audacity.sourceforge.net/) and your exisiting sound card. You can also try just recording when the birds are chirping using something like the freeware Vox recorder (http://freeweb.supereva.com/ninopo.freeweb/index.htm?p) but the theory of that is better than the practice - it's easier to pick out the loud bits in Audacity.

[do re meep meep]

Thanks for the hints! My birdbox is only a few feet behind the backwall of my house. I like to shoot some videos (with an inexpensive DV camcorder) from inside the house, and wonder how I best capture the audio as well. There is power available for the microphone from an outlet in the backwall. If it is a wired microphone, then the cable to the computer in the house would be 20 feet or less. Come to think of it, how do I synchronize audio and video? Appreciate any thoughts.

[ermine]

20 feet is dead easy, go for a wired solution if it's doable. It'll save you money, sound better and you've probably got to run a cable in anyway. If your DV camcorder has a mic input then use that and synchronisation won't be a problem.

If you're going to be putting the mic inside the box then you are into the realms of DIY anyway. The good thing is the mic is protected from wind. What people normally use there is an electret insert, for about $1.50 at Radio shack. Most camcorders can power these down the cable using plug-in power (the camcorder sends the power down the audio cable that brings back the signal).

If you still favour wireless a standard spy bug will work over this range and they almost always use one of these mics and would take the signal to your FM tuner (in mono). You could record this using your PC (record 48kHz sampling rate, you can use your soundcard and something like the free Audacity). Or you could feed it into your camcorder, though if you are going in via the mic input you will need an attenuator of about 20dB - a music store or possibly radio shack may be able to help there.

If you record the soundtrack separately then most video editing apps allow you to time-shift the audio track. Import the extra audio and slide it using the waveform and listening. You will make this job a LOT easier by starting the recordings at almost the same time, and possibly playing the sound from your tuner through the hifi so the camcorder records the speakers. Though you will discard that sound on resynchronisation, it will help with syncing no end.

But an electret insert, 30 feet of standard audio mini cable, a 3.5mm jack plug and a few solder joints are the cheapest and best quality way to do that - assuming your camcorder has a mic input!.

As long as you are using digital recording of the sound then if you get the beak-sync right at the start it won't drift out over the duration of a MiniDV tape.

If you don't fancy the soldering job you could make do with a PC mic and a long 3.5mm jack extension lead or two and some creative woodwork. You might find some ideas from
http://www.birdhousespycam.com/index.html and
this

http://web.syr.edu/~bpburtt/Birds/May16-04.htm

may also be of interest

[do re meep meep]

Thanks for the recommendation, ermine! OK, then, let this be plan A:

...an electret insert, 30 feet of standard audio mini cable, a 3.5mm jack plug and a few solder joints are the cheapest and best quality way to do that - assuming your camcorder has a mic input!

Some follow-up questions:

Is this the electret microphone from Radio Shack?
http://www.radioshack.com/product/index.jsp?parentPage=search&summary=summary&cp=&productId=2062215&accessories=accessories&kw=electret+microphone&techSpecs=techSpecs&currentTab=summary&custRatings=custRatings&sr=1&features=features&origkw=electret+microphone&support=support&tab=techSpecs

The electret microphone device does not seem to have a polarity, i.e. it does not seem to matter which leg I solder to the inner conductor of the audio mini cable and which leg I solder to the outer conductor. Is this correct?

I have a (short) piece of audio mini cable that has a grey color. I can still close the window with the cable going from the outside to the inside of the house, but it is tight. What is the thinnest, most flexible audio mini cable?

Unfortunately, my antique camcorder does not have a mic input. But I will have to buy a camcorder for family use anyway, the antique one does not really cut it anymore. I looked at the Sony line-up, and the first from the bottom that has a mic input is the model DCR-HC96 http://www.sonystyle.com/webapp/wcs/stores/servlet/ProductDisplay?catalogId=10551&storeId=10151&langId=-1&productId=11038809 It has the mic input on the “Active Interface Shoe” (= a kind of docking station?) I wonder if the mic input will power the electret microphone in the above which requires 3 Volts – 10 Volts.

[ermine]

I'd be leery of the Active interface shoe. Sony have had a history of using proprietary interfaces that are non-standard (Memory Stick etc) and these guys

http://dvinfo.net/conf/showthread.php?t=82703

and

http://www.camcorderinfo.com/content/Sony-DCR-HC96-Camcorder-Review/AudioPlaybackConnectivity.htm

seem to be sweating it. You want bog-standard 3.5 mm jack, ideally with plug-in-power. F'rinstance this

http://www.camcorderinfo.com/content/Canon--Optura-50-Camcorder-Review.htm

gives you an audio input and manual audio level control to boot (which is a great help with bird sounds, as they are infrequent and auto level tends to rack up the gain between chirps which is not ideal)

It does matter which way round you wire the electret insert. It won't work the wrong way round. They should provide a datasheet which will show this, otherwise visually inspect the device and whichever terminal is connected to the case is the negative (screen) terminal and the other one goes to the centre conductor.

As for cable, while you're at RS for the mic ask them for the smallest screened single audio cable they havel. It does need to be screened for a cable of that length, but they should be able to find something suitable.

[do re meep meep]

I just want to say another thank you to ermine for his comments, I feel that I have fledged now and can explore on my own.