hilleyja
Posts: 2184
Joined: 1/7/2002 From: Salem,
WV, USA Status: offline
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[QUOTE]...I will also say that I had servos marked AUG2001 and they worked flawless on the first 4 flights. Between the 4th flight and the next one I had heard of the programming issue so I hooked them up to the programmer and reset them. On the next flight the one failed. So is it something in the programming... that's the only thing I changed from the 4th great flight to the 5th and last flight. Who knows but best of luck to Mike to find a resolve. [/QUOTE] There is something curiously coincidental about this statement. Although my servo did not fail after I reset the program I did reset it after it failed. Mike from Hitec insists the problem with these servos were/are not related to the digital circuitry and/or their firmware programming -- I think your scenario and the following belies that: As I stated before; 1) I initially used a Futaba R28DF 8-channel RX with a Hitec chnl 35 Xtal for my initial setup (this configuration was only intended to be used to set up the pushrods and pull-pull controls for the tail surfaces). This setup worked fine and I detected no problems with the (2) HS-5625s and (1) HS-5645. Although my use of this setup was not real extensive, I did put those servos through many maximum left and right deflections -- again no problems. 2) When it came time to setup the throttle channel I also replaced the Futaba RX with a Hitec Supreme 3200 8-channel RX. 3) My configuration upon startup of the RX was now (2) HS-5625s, (1) HS-5645, and (1) HS-422. Each servo was installed in a separate RX channel. The (2) HS-5625s were setup in an "AILEVATOR" mode with channels 2 & 8 with no y-connector and no extensions -- servos were direct connected to RX. 4) BTW, my TX for both of these setups was the Futaba 9C. 5) Within 5 seconds of energizing the RX the channel 2 HS-5625 immediately deflected to maximum left, a full 45 degrees from neutral. 6) I disconnected the failed servo from the RX and hooked it up to the Hitec programmer and ran the "progra reset" function. I was awarded with the "success" response. [COLOR=red]During the "program reset" activities the servo was commanded to deflect full left first and then full right. This occurred with no indication of problems[/COLOR]. 7) I then activated the "auto self test" and observed that the servo only deflect a couple of degrees around neutral. I could not get the servo to move normally. I redid the "program reset" and it still would not deflect normally. 8) I replaced the Jan 02, version 1.02 servo with an HS-5625 lableled as Mar 02, version 1.03. Setup was normal and no problems with the servo. 9.) Three days later in preparation to box up the failed servo to return to Hitec and again hooked it up to the Hitec programmer and ran the "program reset" function. I subsequently ran the "auto self test" and this time the servo reacted normally. Conclusion: The servo was in a failed state for a period of time and then was able to be reset. What component degrades and stays degraded for a couple of hours, only to return to normal a few days later? BTW, for those thinking heat is involved here. I reset that servo after a couple of hours since its failure and it still stayed failed -- a couple of hours is more than sufficient time for thermal degredation on an IC to reverse itself. I know these facts only further confuse the issue, but maybe there is someone out there that can make some sense of it. I am returning the servo to Hitec for replacement -- it failed once and I'm certainly not going to install it in an airplane again.
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Jim Hilley AMA #671825 RCCA# 758 Twist 150 Brotherhood #14
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