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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Comic Sans MS";color:#1F497D'>Hi Mike….<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Comic Sans MS";color:#1F497D'>I have noticed a sound like a ‘knock’ on the side of the fuselage on 3 different airplanes, Plett 30-10 and Advance and three ESC…a CC 80HV ICE and 2 CC 80HV ICE V2.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Comic Sans MS";color:#1F497D'>I’ve looked at logs and don’t recognize any problems.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Comic Sans MS";color:#1F497D'>I have always wondered what the sound was…at first I thought it might have caused by the cables to the rudder and elevator slapping the side if the fuse but they are fastened down tightly.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Comic Sans MS";color:#1F497D'>Then…I thought it might be caused by the wheels rattling….<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Comic Sans MS";color:#1F497D'>It seems to happen most of the time on an up line.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Comic Sans MS";color:#1F497D'>It doesn’t seem to be a problem…yet…but I would like to know what is causing it.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Comic Sans MS";color:#1F497D'><o:p> </o:p></span></p><div><p class=MsoNormal><b><span style='font-size:10.5pt;font-family:"Comic Sans MS";color:#1F497D'>Dave Harmon<o:p></o:p></span></b></p><p class=MsoNormal><b><span style='font-size:10.5pt;font-family:"Comic Sans MS";color:#1F497D'>NSRCA 586<o:p></o:p></span></b></p><p class=MsoNormal><b><span style='font-size:10.5pt;font-family:"Comic Sans MS";color:#1F497D'>K6XYZ[at]sbcglobal[dot]net<o:p></o:p></span></b></p><p class=MsoNormal><b><span style='font-size:10.5pt;font-family:"Comic Sans MS";color:#1F497D'>Sperry, Ok.<o:p></o:p></span></b></p></div><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Comic Sans MS";color:#1F497D'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #B5C4DF 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>From:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> nsrca-discussion-bounces@lists.nsrca.org [mailto:nsrca-discussion-bounces@lists.nsrca.org] <b>On Behalf Of </b>Michael Cohen<br><b>Sent:</b> Sunday, August 19, 2012 3:48 PM<br><b>To:</b> NSRCA<br><b>Subject:</b> [NSRCA-discussion] Hacker C50-14XL comp/Castle 80HV Ice 2 combo "backfiring"<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal style='margin-bottom:10.0pt'><span style='font-family:"Calibri","sans-serif"'>I had a strange problem today with a Hacker C50-14XL comp/Castle 80HV Ice 2 combo. Sounded like the motor/ESC was backfiring, so I stopped flying. I had 56 flights before today, and this is the first time I noticed the backfiring. I was at a contest last weekend, so if it had occurred there, I think people, including me, would have noticed.<o:p></o:p></span></p><p class=MsoNormal style='margin-bottom:10.0pt'><span style='font-family:"Calibri","sans-serif"'>Well, upon taking it home and hooking it up to the computer, I did find that all my settings were still where they were supposed to be, so there was no unexplained change there. I downloaded the data logger, but I really didn’t check it too closely. I then went online to look for backfiring problems and the only thing I found was a sample rate of 10hz (mine was at 1hz) could cause a backfire. I also noted a comment that if you run out of data logging space, that could cause a “ticking”. I did not have a ticking, but I decided to clear all stored logging information and set the sampling rate to "disabled". I ran the motor/ESC for about a minute on the ground with no evidence of a backfire. Could the data logging/storage space been it? Has anyone else had a similar experience? FYI, here is my program:</span><o:p></o:p></p><p class=MsoNormal style='margin-bottom:10.0pt'> <span style='font-family:"Calibri","sans-serif"'><o:p></o:p></span></p><p class=MsoNormal style='margin-bottom:10.0pt'><span style='font-family:"Calibri","sans-serif"'>Brake Strength: 30% <o:p></o:p></span></p><p class=MsoNormal style='margin-bottom:10.0pt'><span style='font-family:"Calibri","sans-serif"'>Brake Delay: No delay <o:p></o:p></span></p><p class=MsoNormal style='margin-bottom:10.0pt'><span style='font-family:"Calibri","sans-serif"'>Brake Ramp: Medium <o:p></o:p></span></p><p class=MsoNormal style='margin-bottom:10.0pt'><span style='font-family:"Calibri","sans-serif"'>Cutoff Voltage: 3.2<o:p></o:p></span></p><p class=MsoNormal style='margin-bottom:10.0pt'><span style='font-family:"Calibri","sans-serif"'>Current Limiting: Normal <o:p></o:p></span></p><p class=MsoNormal style='margin-bottom:10.0pt'><span style='font-family:"Calibri","sans-serif"'>Cutoff Type: Soft Cutoff <o:p></o:p></span></p><p class=MsoNormal style='margin-bottom:10.0pt'><span style='font-family:"Calibri","sans-serif"'>Motor Start Power: low (39)<o:p></o:p></span></p><p class=MsoNormal style='margin-bottom:10.0pt'><span style='font-family:"Calibri","sans-serif"'>Motor Timing: Custom (3) <o:p></o:p></span></p><p class=MsoNormal style='margin-bottom:10.0pt'><span style='font-family:"Calibri","sans-serif"'>PWM Rate: 8khz <o:p></o:p></span></p><p class=MsoNormal style='margin-bottom:10.0pt'> <o:p></o:p></p><p class=MsoNormal style='margin-bottom:10.0pt'><span style='font-family:"Calibri","sans-serif"'>Regards,<o:p></o:p></span></p><p class=MsoNormal style='margin-bottom:10.0pt'><span style='font-family:"Calibri","sans-serif"'>Mike Cohen<o:p></o:p></span></p><p class=MsoNormal style='margin-bottom:10.0pt'><o:p> </o:p></p><p class=MsoNormal><span style='font-size:14.0pt'> </span><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'><o:p></o:p></span></p></div></div></div></body></html>