naturerecordists
[Top] [All Lists]

Re: Long cable questions

Subject: Re: Long cable questions
From: Rob Danielson <>
Date: Fri, 22 Aug 2003 00:30:38 -0500
>Thanks to several of you for suggestions about sticking a mic out on a
>mudflat and
>running a cable back to a recorder. This sounds like a "grown up" version of
>what I did when I put a mic next to
>a Carolina Wren nest (in our eaves) with a long enough wire to reach a
>recorder. (Worked like a charm.)
>
>This is also one of two approaches I've considered to recording Prairie
>Chickens (or Spruce Grouse) on a lek.
>The other approach I thought of was to dump the recorder and mic on the lek
>long before dawn. Turning it on might be a problem (though I thought maybe a
>radio-control would be possible), so my plan was to use an MD set in "long
>record mode"  that would do almost 4 hours in low quality mono, and hope the
>birds started before the batteries died or the the disk filled. For my one
>chance, (I don't live near any leks) it got very cold overnight and the
>batteries died long before there was any activity, even though I'd but the
>recorder in a styrofoam box. (Perhaps a small heater?) But the moring was
>calm and clear, the sun rising behind us, and the displays, viewed through a
>scope from about 1/2 mile were wonderful, so I have no regrets.
>
>My questions, then, are:
>
>1. How long a cable can I hope to use? I assume it should be shielded? Do I
>need an extra "repeater" or "amp" to use a really long cable? Is it enough
>to get inexpensive, shielded (3-conductor) wire and solder (I've learned to
>do that now!) connectors on each end, or are there other things to consider?

A couple of hundred feet most always works for me, mic level, rural 
places. I haven't gone beyond 300' but should be okay.  I've used 
expensive mic cable and even plain old 3 conductor studio wire. The 
later is stiff but cheaper and sounds the same to my ears. If you 
believe you are losing level or getting radio interference and have a 
portable power mic pre, leave it out it near the mic(s) and cable the 
signal from the line level outputs back to the recorder. Try to keep 
the cable off wet ground.

>
>2. What about my idea of sticking a recorder out near the birds and turning
>it on from a distance? Have you tried it? Can anyone offer suggestions about
>how to do it?
>
>3. My first recorder (a hand-sized Sony) had a "voice acitvated" recording
>system that would start recording at either one of two user-selectable sound
>levels. When I tried sticking it next to an American Robin nest, it switched
>on and off too fast to make a useful recording. Has anyone considered /built
>improved versions of this sort of system? I guess I could program a laptop
>to start recording at a given level and keep going for a while. Or is there
>a way to "fiddle with" commerically available voice-activated recording
>systems to adjust when they turn off? Could I use one of these (cheap, I
>hope) systems to turn on recording by a higher quality recorder?

AC-powered laptop, headphones, mics running out several hundred feet 
makes for good sleeping. Eight hour takes. Burn them to DVD and hit 
record again.  You can spot the loud events on the waveform.  Yes, 
portable power for long periods is involved--especially  for laptops. 
For the smaller recorders, a sled of D size rechargeables should run 
an MD or DAT until the tape runs out and more.   You can get $200 
used DAT recorder and leave 3 hour tapes rolling in the woods.  The 
wind makes activation a challenge but I've seen free level activation 
software for mac at least.  Rob D.


>
>As always, I look forward to everyone's suggestions and insights. With all
>your help, someday I'll start to think I know what I'm doing!
>
>Thanks,
>Steve P
>



________________________________________________________________________
________________________________________________________________________

<Prev in Thread] Current Thread [Next in Thread>
Admin

The University of NSW School of Computer and Engineering takes no responsibility for the contents of this archive. It is purely a compilation of material sent by many people to the naturerecordists mailing list. It has not been checked for accuracy nor its content verified in any way. If you wish to get material removed from the archive or have other queries about the archive e-mail Andrew Taylor at this address: andrewt@cse.unsw.EDU.AU