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<div>I do not remember the details. Litton made the actual vibrator unit. Several companies assembled vibrator trucks and custom off road buggies. We did both. To long ago for me to remember all the details.</div><div><br></div><div>We also made a weight drop truck. Used in the deserts. Had a 2000 lb weight that was winched up 10 ft high and dropped on radio command.</div><div><br></div><div>The main problem with those was the weight provided shade. Precious shade in the desert. That the Arab crew would use for brakes. One stray radio signal and would need a new crew.</div><div><br></div><div>That happened a number of times. That was a international truck with the weight hanging off the back. Sorry could not find a photo. They still exist but the weight is enclosed for some reason. 😆</div><div><br></div>
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On Saturday, July 25, 2020, 07:45:41 PM CDT, Howard Pletcher <hrpletch@gmail.com> wrote:
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<div><div id="ydp2a25a62eyiv2059453040"><div><div dir="ltr"><div dir="ltr"><div class="ydp2a25a62eyiv2059453040gmail_default" style="font-family:tahoma, sans-serif;">Very interesting. Thanks for your info. When I was at IH/Navistar, I know some trucks were used as thumpers, but had no idea just what they did--and after a little searching, now see what is being done, but still don't begin to understand how it tells the geologists anything. </div><div class="ydp2a25a62eyiv2059453040gmail_default" style="font-family:tahoma, sans-serif;"><br clear="none"></div><div class="ydp2a25a62eyiv2059453040gmail_default" style="font-family:tahoma, sans-serif;">Where are the trucks you worked with built? What engine powers them?</div><div class="ydp2a25a62eyiv2059453040gmail_default" style="font-family:tahoma, sans-serif;"><br clear="none"></div><div class="ydp2a25a62eyiv2059453040gmail_default" style="font-family:tahoma, sans-serif;">I am continually amazed by the wide variety of expertise accumulated by us "dumb farmers that play with old tractors", haven't seen any brain surgeons on here yet, but I wouldn't be surprised if one pops up. Very interesting group.</div><div class="ydp2a25a62eyiv2059453040gmail_default" style="font-family:tahoma, sans-serif;"><br clear="none"></div><div class="ydp2a25a62eyiv2059453040gmail_default" style="font-family:tahoma, sans-serif;">Howard</div></div><br clear="none"><div class="ydp2a25a62eyiv2059453040gmail_quote"><div class="ydp2a25a62eyiv2059453040yqt1459776082" id="ydp2a25a62eyiv2059453040yqtfd56805"><div class="ydp2a25a62eyiv2059453040gmail_attr" dir="ltr">On Sat, Jul 25, 2020 at 1:08 PM ustonThomas Mehrkam <<a shape="rect" href="mailto:tmehrkam@sbcglobal.net" rel="nofollow" target="_blank">tmehrkam@sbcglobal.net</a>> wrote:<br clear="none"></div><blockquote class="ydp2a25a62eyiv2059453040gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex;"><div style="font-family:Helvetica, Arial, sans-serif;font-size:16px;"><div></div>
<div dir="ltr">The ones we used in the vibrator trucks were rated for over 300 hp and cost only $32,000 each. We used them to make it easyier to control the spacing between trucks. Had ultrasonic sensors to measure the distance between the trucks. They operated as an array and spacing was important. Some array designs had different spacing between each truck.</div><div dir="ltr"><br clear="none"></div><div dir="ltr">The hydrstatic transmission was much easier to precisely control spacing between trucks. Three to five trucks in an array was common and there would be multiple fleets of trucks that would stop shake the ground then pull up the pad and move forward to the next shot point. While they were moving another fleet would shake the ground. Speed things things up a bit. </div><div dir="ltr"><br clear="none"></div><div dir="ltr">The older trucks were built on Mac Truck chases with normal transmissions. Not having a drive shaft from the front and rear drive allowed putting a bigger vibrator in the middle to get more signal. </div><div dir="ltr"><br clear="none"></div><div dir="ltr">In the US the wheeled version is common. Some places use the tracked version.</div><div dir="ltr"><br clear="none"></div><div dir="ltr">This is the company I use to work for. The name changed many times. When I joined the name changed to Geosource that was the name it was know by for many years.</div><div dir="ltr"><br clear="none"></div><div dir="ltr"><span><a shape="rect" href="https://www.inovageo.com/products/category/source-products/vibrators" rel="nofollow" target="_blank">https://www.inovageo.com/products/category/source-products/vibrators</a></span><br clear="none"></div><div dir="ltr"><br clear="none"></div><div dir="ltr"><span><a shape="rect" href="https://www.youtube.com/watch?v=8EVilzqcggk" rel="nofollow" target="_blank">Seismic Vibrator truck</a></span><div><br clear="none"></div><div id="ydp2a25a62eyiv2059453040m_-4842885578549511306m_1472968588542696885gmail-m_4105975687844552525ydp799752a1enhancr_card_5974204822" style="max-width:400px;font-family:YahooSans, Helvetica, Arial, sans-serif;"><a shape="rect" href="https://www.youtube.com/watch?v=8EVilzqcggk" style="text-decoration:none;color:rgb(0,0,0);" rel="nofollow" target="_blank"><table border="0" cellpadding="0" cellspacing="0" style="max-width:400px;"><tbody><tr><td colspan="1" rowspan="1" width="400"><table border="0" cellpadding="0" cellspacing="0" width="100%" style="max-width:400px;border-width:1px;border-style:solid;border-color:rgb(224,228,233);border-radius:2px;"><tbody><tr><td colspan="1" rowspan="1" valign="top" bgcolor="#000000" height="175" style="background-color:rgb(0,0,0);background-size:cover;border-radius:2px 2px 0px 0px;min-height:175px;"><table border="0" cellpadding="0" cellspacing="0" style="width:100%;"><tbody><tr><td colspan="1" rowspan="1" valign="top" bgcolor="transparent" style="background-color:transparent;border-radius:2px 2px 0px 0px;min-height:175px;"><table border="0" height="175" style="width:100%;min-height:175px;"><tbody><tr><td colspan="1" rowspan="1" style="text-align:left;padding:15px 0px 0px 15px;vertical-align:top;"></td><td colspan="1" rowspan="1" style="text-align:right;padding:15px 15px 0px 0px;vertical-align:top;"><div></div></td></tr></tbody></table></td></tr></tbody></table></td></tr><tr><td colspan="1" rowspan="1"><table align="center" border="0" cellpadding="0" cellspacing="0" style="background:rgb(255,255,255);width:100%;max-width:400px;border-radius:0px 0px 2px 2px;border-top:1px solid rgb(224,228,233);"><tbody><tr><td colspan="1" rowspan="1" style="background-color:rgb(255,255,255);padding:16px 0px 16px 12px;vertical-align:top;border-radius:0px 0px 0px 2px;"><img src="https://s.yimg.com/nq/storm/assets/enhancrV2/23/logos/youtube.png" height="36" style="min-width:36px;margin-top:3px;"></td><td colspan="1" rowspan="1" style="vertical-align:middle;padding:12px 24px 16px 12px;width:99%;font-family:YahooSans, Helvetica, Arial, sans-serif;border-radius:0px 0px 2px;"><h2 style="font-size:14px;line-height:19px;margin:0px 0px 6px;font-family:YahooSans, Helvetica, Arial, sans-serif;color:rgb(38,40,42);max-width:314px;">Seismic Vibrator truck</h2><p style="font-size:12px;line-height:16px;margin:0px;color:rgb(151,155,167);"></p></td></tr></tbody></table></td></tr></tbody></table></td></tr></tbody></table></a><div style="width: 100%; min-height: 100%;"><div><div><u></u><u></u><u></u><u></u><u></u><u></u></div></div></div></div><div><br clear="none"></div><div><br clear="none"></div><div><br clear="none"></div><br clear="none"></div><div><br clear="none"></div></div></blockquote></div></div></div></div></div><div class="ydp2a25a62eyqt1459776082" id="ydp2a25a62eyqtfd84797">_______________________________________________<br clear="none">AT mailing list<br clear="none"><a shape="rect" href="mailto:AT@lists.antique-tractor.com" rel="nofollow" target="_blank">AT@lists.antique-tractor.com</a><br clear="none"><a shape="rect" href="http://lists.antique-tractor.com/listinfo.cgi/at-antique-tractor.com" rel="nofollow" target="_blank">http://lists.antique-tractor.com/listinfo.cgi/at-antique-tractor.com</a><br clear="none"></div></div>
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