I am a naturalist, educated in physics, who worked in industry as a sound and vibration engineer for many years. I get a lot of enjoyment from observing natural things that go on around me and in making real connections with the natural world. Many of my interests relate to natural and man-made sources of sound and vibration out in the environment but I throw in a few observations and posts on other subjects that catch my attention too.
Murmurs from the Earth…Whispers from the Sky is the more analytical half of my personal blogosphere. My quiet, more reflective side expresses itself at The Quiet Way. In both I share some of the things around me that I have found interesting. I also post some black and white photographs at lightmonkey dreams. I hope you enjoy them…comments are welcomed.
Sir,
First, Merry Christmas!
I ran across your weblog while searching for information to complete a Lehman Seismograph which I am building with my 6th grade math and science students.
I must tell you that I became engrossed with your posts at The Quiet Way and they have distracted me from my search for the information I think I need to complete the seismograph.
But I wonder if I may shoot a few questions your way regarding your seismometer?
I’d like to know how long your boom is and whether you gave any thought to the boom’s center of mass when you determined where and how to attach the suspension wire.
I also would be interested to know the height of your support tower and the distance between the boom pivot point and the suspension point at the top of the tower.
Finally, I note that most builders of Lehman instruments suspend the boom and inertial mass from an inverted U shape of steel pipe as it appears in the original Walker article. But I am wondering if there is any reason why an un-guyed monopole of maybe 1″ pipe, or even a square steel tube welded to a flat steel plate wouldn’t work just fine?
I would be grateful for any assistance you are willing to offer.
Christopher Dahle
6th Grade Math and Science
Ortega Middle School
Alamosa, Colorado
Comment by Christopher Dahle — December 29, 2008 @ 12:34 am
Merry Christmas Christopher,
Thanks for your comments and questions. I’ll send you an email with the information you requested, a couple of small photographs, and a couple of other suggestions.
Mic
Comment by Mic — December 29, 2008 @ 8:50 am
Thanks again Mic for your detailed and very helpful suggestions. My ADC arrived today and excepting a few nuts and bolts and a final decision on what to do about an amplifier, I finished rounding up all the parts this afternoon.
I’m looking forward to playing with the ADC. I’ve never had access to anything like it before.
Happy New Year,
Chris
Comment by Christopher Dahle — December 30, 2008 @ 11:28 pm
Hi, This is a great page. I am always looking for good examples of sound recordings for classes in underwater acoutsics but air acoustics often work well. Would you consider posting or sharing some of your recordings you use in your examples?
Regards,
Bud Vincent
Research Associate Professor]
Ocean Engineering
University of Rhode Island
Comment by Bud — February 6, 2010 @ 11:13 pm
Bud,
Thank you for commenting. I would be happy to send you some recordings if I can find them and will contact you via email regarding the specifics.
Mic
Comment by Mic — February 7, 2010 @ 8:59 am