Parabolic listening device - Easy build assistance requested

[Bigfoot]

I have a friend who has a cabin about 35 Km into the bush in northern Ontario, Canada. He has invited my wife and I to spend a week with him and his wife for the past three years. He has stated he would like to have a parabolic listening device on his cabin so that he can listen to night sounds from inside the cabin. Not knowing how realistic it would be to build a device from an old satelite dish, the small grey kind, or even how to begin to build one with any off the shelf electronic parts, on a pretty limited budget, I would like to throw it out to anyone who might like to assist me. I live just across the river from Detroit, MI, so getting parts from the U.S. would not be a problem if your familiarity is mostly with U.S. parts and ready to use electronics. Our next trip to the cabin is in September 2013, and I would like to be able to have something to bring with me as a gift for their generosity. If you can also provide me with an idea for a method of remotely directing the dish in the most economical way, even if that is in a mechanical rather than in an electronic way, that would be very much appreciated as well. Thank you.

 

[ronv]

I was going to build one once for a friend that records birds, but if you want to use ready made parts I think eBay might be the best bet.

https://www.ebay.com/sch/i.html?_tr...&_nkw=parabolic+microphone&_sacat=0&_from=R40

 

[misterT]

Not knowing how realistic it would be to build a device from an old satelite dish,

All you need to do is to attach a microphone to the focal point of the dish:

http://www.scienceprog.com/long-range-directional-microphones-myth-and-reality/

 

[audioguru]

The microphone tutorial has horrible Engrish and spelring.

The size of the dish also determines the low frequency cutoff.
What makes "night sounds in the bush" anyway? Boring! It is like watching paint dry.
Oh, maybe for spying on neighbours?

 

[unclejed613]

a more interesting project would be what's called a "organ pipe microphone"... something like this: http://members.shaw.ca/roma/shotgun.html

 

[chemelec]

These Dimensions are Based on OCTAVES.
Produces Better results than that other one.
http://chemelec.com/Projects/Shotgun-Mic/Shotgun-Mic.htm

 

[Bigfoot]

The microphone tutorial has horrible Engrish and spelring.

The size of the dish also determines the low frequency cutoff.
What makes "night sounds in the bush" anyway? Boring! It is like watching paint dry.
Oh, maybe for spying on neighbours?

All sorts of interesting sounds can be heard at night. Everyone has his own thing, right? Whether it be electronics or one of the zoological or biological sciences. Since my buddy's cabin is 35 Km into the bush, he could, I suppose, be trying to listen in on a hermit trapper mumbling to himself. That could be LOADS of fun.

Other than the grammar and spelling, is the tutorial useful, and, pardon my ignorance, how do I access it? Thanks

 

[atferrari]

There is also a design using a 4-side "funel" following an exponencial law.

Built a small prototypr with cardboard and vinylic glue. It works.

Some info here: https://forum.allaboutcircuits.com/showpost.php?p=244604&postcount=32

BTW, what is "spelring"?

 

[unclejed613]

"spelring" is how "spelling" is pronounced in "chinglish"....


the longer dimensions, while it would make a nice sounding microphone, are a bit unwieldy. the 36 inch version as can be seen from the article, needs support members. the 54 inch version would be difficult to mount, and difficult to transport, etc... i built one of the 36 inch models and it fits nicely in a mailing tube for blueprints.

the actual purpose of the various length tubes isn't really to provide resonant chambers, but to provide phase cancellation for any audio source that is off-axis.

 

[audioguru]

BTW, what is "spelring"?

Didn't you notice the horrible English spelling in the tuorial??
Some Oriental people mix up or cannot speak "L" so they pronounce it as "R".
They say "Engrish" instead of English and say "sperring" instead of spelling or maybe the other way around.

 

[atferrari]

Didn't you notice the horrible English spelling in the tuorial??
Some Oriental people mix up or cannot speak "L" so they pronounce it as "R".
They say "Engrish" instead of English and say "sperring" instead of spelling or maybe the other way around.

Oh yes. No doubt it is hard for them!

I meet them fom time to time in vessels coming to this part of the world.

 

[audioguru]

Vessel??
Sometimes a boatload of Orientals comes to the West coast of Canada. They claim to be refugees but actually they paid a fortune for the trip.
The govenrment of Canada pays for their hotel room and also pays for restaurant meals. Maybe for 6 months or more then they go to court and are deported back to their country (Canadian taxpayers pay for their hotel room, restaurant meals and airplane trip away from here).

 

[atferrari]

Just crew members

Sorry, I should have say "vessels" (corrected now in my previous post) where they come as crew members.

As a Supercargo, I worked with vessels with up to 14 different nationalities amongst crew. Nowadays, very seldom the vessel's flag says anything about the Owners or crew.

Yes, communication is sometimes a problem. Thanks God, the few times we had real emergencies on board, we were all speaking the same language.

 

[Bob Scott]

Edmund Scientific usually has an assortment of parabolic reflectors. Here are three. 12, 18 and 24 inch dia:

https://www.scientificsonline.com/large-parabolic-reflectors.html

They also are featuring a complete but smallish parabolic listening device on sale at half price.

If you're experimenting, I've noticed that some woks look very parabolic. If you buy one and it doesn't work well, you can always use it to stir fry veggies.

 

[Bigfoot]

I don't get it. Why did I get a completely unrelated message from atferrari to my request for assistance in building a parabolic microphone? I quote : "Sorry, I should have say "vessels" (corrected now in my previous post) where they come as crew members.

As a Supercargo, I worked with vessels with up to 14 different nationalities amongst crew. Nowadays, very seldom the vessel's flag says anything about the Owners or crew.

Yes, communication is sometimes a problem. Thanks God, the few times we had real emergencies on board, we were all speaking the same language. "

Strange. It came directly to my email.

 

[alec_t]

Just google 'parabolic dish microphone'. There's heaps out there, together with amp schematics.

 

[atferrari]

Strange. It came directly to my email.

Strange to me also. I just posted here.

 

[Bigfoot]

Help in building Parabolic microphone with some kind of off the shelf preamp

I have been scouring the internet as you suggested, but other than the very expensive set-ups(CDN $450 - $500 and up) and the very low end with very small dishes, I haven't been able to find anything. I began posting here to see if there is anyone who could assist me in making a parabolic mic set-up in a way that even someone who is totally electronically challenged, like me, though fully capable of assembling something from parts that need no schematics or soldering circuit boards, just some clear instructions, could put together. In other words, what I am looking for is someone who can give me simple instructions and who can make suggestions that will ultimately result in a good quality parabolic microphone for a cost I can afford (and that is not even close to what they are charging retail). If you feel that my request can be productively dealt with by yourself, or if you can suggest someone else who is by heart a patient teacher and would likely be able to help, I'd be very grateful. It sucks to be so helpless in this area. And I am too old to start learning all that electronic jargon, formula's and theory. I hope you or someone out there can help. Thanks.

 

[alec_t]

You may be able to source cheaply an old cassette tape recorder with a plug-in microphone. Alternatively a solid-state dictation recorder would do. Just mount the mic facing the dish (an old satellite dish with a foil liner, a trash-bin lid, a saucepan lid,......) with the mic opening at the dish focus (experiment for best position).

 

[ronv]

I keep coming back to something like this:

**broken link removed**

It would be hard to match it for price or performance with "off the shelf" components. Note that you still need something for the final amplifier, like a recorder with headphones.