Hi John,
Thanks for your time to respond...
I'm a great tinkerer and do-it-yourself sort of a guy, I get great pleasure=
of doing my own thing and then refining it and doing it again most likely
based on what, hopefully, I have learned along the way...
Actually, my first stab at building a dish microphone is already
underway... Quite by chance, I came upon a source of inexpensive stainless=
steel woks, 16" diameter... This is made of a light weight stainless made=
the same way many stainless cookware bowl shaped items are made and
surprisingly, this wok has a good parabolic shape and when pointed at the
sun, sets a stick of wood on fire at a point 5 5/8" above the bottom center=
of the bowl... This was a very crude test made to determine how well the
wok would focus and at what height above it the point of focus was located.
I have not measured and calculated to see how true a parabola it is,
however for a first attempt, to see what I can learn as an experiment, I'm=
going to mount a microphone on it and see how it does.
In the long run, to my way of thinking, stainless would be too heavy a
material for portability, however if this foolish wok proves to have the
right shape, it will make a good mold for plastic or fiberglass fabrication=
...
You can see 5 photographs of my test and result made this afternoon here:
http://www.4shared.com/dir/2_X_hmub/Dish_tests.html
In
At 03:04 AM 7/17/2010 +0000, you wrote:
>Hi Mitch,
>
>Building a parabolic system from scratch could certainly be fun, but
>unless you need something bigger than the Telinga dish, $150 for the raw
>dish is a good value for the base of your system. I did, however, make a=
>dish for less than five dollars by finding a scrap piece of ridged foam
>insulation, cutting out overlapping rings, gluing them together, shaping
>with a wood rasp, sanding, and then using wood glue to glaze a reflective=
>surface. First though, I calculated the shape, and cut a parabolic arc
>template out of plywood. For my Telinga dish, I used a variety of parts
>from the plumbing section at the hardware store to mount the dish.
>
>John Hartog
>
>--- In Mitch Hill <> wrote:
> >
> > Dan,
> >
> > Thank you for the information And thanks to Paul for your comment.
> >
> > I think one of the first sites I visited in my search on line for
> parabolic
> > dish microphone information was the NatureSongs web site and I listened=
to
> > the comparison recordings made with the ME66 (which I have and use) and=
> the
> > Telinga dish and it is truly impressive. If I were interested in
> > purchasing a complete system of that type, there is no doubt in my mind
> > that is what I'd purchase.
> >
> > However, a key part of what my plan is a learning experience... In the
> > past I have worked with refining a design of a hand held diver pinger
> > locater used in underwater work which was a very similar looking device=
> but
> > much smaller. As a result I have some experience and ideas of my own t=
hat
> > need to be exercised before I'm satisfied that I goofed and my fall bac=
k
> > would be a Telinga parabolic dish setup. It is definitely a neat clean
> > design and the sample recordings are impressive to say the least, gives=
me
> > a mark to aim for performance wise.
> >
> > Thanks,
> > Mitch & Shadow...
> >
> >
> > At 10:34 PM 7/15/2010 -0700, you wrote:
> > >A few years ago most of the parabolic dishes were home-brewed. Now tha=
t
> > >Telinga in Sweden manufactures a superior system, you can buy it off t=
he
> > >shelf. Telinga( http://www.telinga.com) is imported by Doug Von Gausig=
,
> > >http://www.naturesongs.com. I do the repairs in the U.S.
> >
> > --
> >
> > Thanks,
> > Mitch & Shadow...
> >
> > http://www.4shared.com/dir/UTASxktL/wildlife.html
> >
> > Shadow's area: http://www.4shared.com/dir/ecfWjyZb/Shadow.html
> >
> >
> >
>
>
>
>
>------------------------------------
>
>"While a picture is worth a thousand words, a
>sound is worth a thousand pictures." R. Murray Schafer via Bernie Krause
>Yahoo! Groups Links
>
>
>
--
Thanks,
Mitch & Shadow...
http://www.4shared.com/dir/UTASxktL/wildlife.html
Shadow's area: http://www.4shared.com/dir/ecfWjyZb/Shadow.html
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