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Crazy radio, battery, servo gremlins...what's your guess?

Crazy radio, battery, servo gremlins...what's your guess?

Old 06-20-2009, 10:51 PM
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Red face Crazy radio, battery, servo gremlins...what's your guess?

I run a Futaba 3PK (older gen) with the FAAST system. It's set to HRS and I was pretty confident (after reading through the manual many times) that I had it setup correctly. Despite my efforts, I continued to lack braking power. Yesterday while running at our local track I accidentally hit the brake/throttle trim and things got all out of whack. I think it overloaded the servo (JR9100S) before I noticed. When I brought it in and re-trimmed it correctly I noticed the servo was fine on the throttle side but on the brake side, at full brake, the servo would jump back then pull again then jump back, almost like it was in ABS mode but very slow. I checked and ABS was turned off. Then while messing with it more I lost almost all of the brake side range of motion. It would barely move. Turns out one of the settings in the radio was turned down too far (don't recall which now). I have no idea how it happened since I didn't touch it since it had been running well. So, in trying to diagnose this I put in a new servo, then a new radio, etc. I ran into the same issues. Finally I put in a new, full charged Rx battery, had someone go through the Tx and reset everything and got it working again but it was still doing the jump back from full range thing. I had to dial the endpoint back quite a bit to get it to stop doing that and now it's working okay. I think my 9100S is still okay. Now I'm dealing with a battery pack that makes the throttle/brake servo cut off about 50% of the time but has no impact on the steering servo. Last race day it came fully unplugged and caused a runaway so this time I had it taped (yes, I'm getting a new connector).

So after all that BS I'm curious if you guys have any ideas why my servo was acting that way, why my Tx mysteriously reset itself in more than one setting (even my steering settings were all whacked up after swapping out servos!), and what would you do to remedy these issues short of replacing everything. I don't have the dough to replace anything right now so making what I have work is the goal.

Thoughts?

Anyone want to buy a race spec RC8 fully modded with radio and servos? I love how this hobby/sport makes you want to give up sometimes!
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Old 06-21-2009, 09:45 AM
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The only thing I can come up with is the battery switch. Go derect and see what happens. I stop useing it long time ago and no more funny stuff.
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Old 06-21-2009, 10:48 AM
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You answered your question about the servo. You fixed it when you backed off the epa, right ? Sometimes when the end point is too far out it will jump and act funny because its under extra load. It cant go any farther because of it being at max. Always adjust your epa to the max throw then back it off a couple of clicks. As long as you do this it will be ok. Im sure your radio has steering dual rate also. I always set my epa to max then use the dual rate to adjust the proper throw.
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Old 06-21-2009, 11:27 AM
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Try another servo
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Old 06-21-2009, 11:37 AM
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Originally Posted by t0adman View Post
I run a Futaba 3PK (older gen) with the FAAST system. It's set to HRS and I was pretty confident (after reading through the manual many times) that I had it setup correctly. Despite my efforts, I continued to lack braking power. Yesterday while running at our local track I accidentally hit the brake/throttle trim and things got all out of whack. I think it overloaded the servo (JR9100S) before I noticed. When I brought it in and re-trimmed it correctly I noticed the servo was fine on the throttle side but on the brake side, at full brake, the servo would jump back then pull again then jump back, almost like it was in ABS mode but very slow. I checked and ABS was turned off. Then while messing with it more I lost almost all of the brake side range of motion. It would barely move. Turns out one of the settings in the radio was turned down too far (don't recall which now). I have no idea how it happened since I didn't touch it since it had been running well. So, in trying to diagnose this I put in a new servo, then a new radio, etc. I ran into the same issues. Finally I put in a new, full charged Rx battery, had someone go through the Tx and reset everything and got it working again but it was still doing the jump back from full range thing. I had to dial the endpoint back quite a bit to get it to stop doing that and now it's working okay. I think my 9100S is still okay. Now I'm dealing with a battery pack that makes the throttle/brake servo cut off about 50% of the time but has no impact on the steering servo. Last race day it came fully unplugged and caused a runaway so this time I had it taped (yes, I'm getting a new connector).

So after all that BS I'm curious if you guys have any ideas why my servo was acting that way, why my Tx mysteriously reset itself in more than one setting (even my steering settings were all whacked up after swapping out servos!), and what would you do to remedy these issues short of replacing everything. I don't have the dough to replace anything right now so making what I have work is the goal.

Thoughts?

Anyone want to buy a race spec RC8 fully modded with radio and servos? I love how this hobby/sport makes you want to give up sometimes!
are 9100s servos digital ?
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Old 06-21-2009, 11:50 AM
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Originally Posted by The Working Man View Post
The only thing I can come up with is the battery switch. Go derect and see what happens. I stop useing it long time ago and no more funny stuff.

+1..too many switch problems..mini deans direct plug in is the only way to go
and lots more room in your box to pack a sandwich
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Old 06-21-2009, 11:53 AM
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Originally Posted by Jaz240 View Post
+1..too many switch problems..mini deans direct plug in is the only way to go
and lots more room in your box to pack a sandwich
no on/off switch problems for me


change them out every so often and no problems .
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Old 06-21-2009, 12:12 PM
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too many connections that could come loose, break, have possible problems. One time the silicone boot had a small tear in it and dirt got in the switch, couldn't turn it off. Broke a plug once. switch failed once causing loss of RX..I dont have to change them occasionally now..because they are gone, makes it much easier to swap out batteries also..try it...you make like it..Plug and play
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Old 06-21-2009, 12:40 PM
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Originally Posted by Jaz240 View Post
+1..too many switch problems..mini deans direct plug in is the only way to go
and lots more room in your box to pack a sandwich
i do like the sandwich idea though
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Old 06-21-2009, 01:02 PM
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I do like the idea of more room. But seems like alot of trouble just to turn your car on and off.
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Old 06-21-2009, 01:15 PM
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They are digital Monty. Could be another reason.
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Old 06-21-2009, 01:57 PM
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Originally Posted by dreaux View Post
I do like the idea of more room. But seems like alot of trouble just to turn your car on and off.
Takes about 20 minutes to solder mini-deans on 2 batteries and the lead from the RX
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Old 06-21-2009, 01:58 PM
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all you need is a 4" or so servo extender and 2 notches cut on the battery box lid so the wires can be out. i do it on the outer side of the box so the wires are easy to reach. the servo extender plugs into the receiver, then the link between the battery and the extender is your on/off switch. also you plug the battery direct instead of through the switch.
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Old 06-21-2009, 05:03 PM
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Originally Posted by Jaz240 View Post
Takes about 20 minutes to solder mini-deans on 2 batteries and the lead from the RX


Cut, Strip, twist, solder, shrink, Done......

20 min



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Old 06-21-2009, 05:54 PM
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Originally Posted by Integra View Post
Cut, Strip, twist, solder, shrink, Done......

20 min



you missed a couple....

Cut, crack open beer, Strip, take a drink of beer, Twist, another drink, Solder, take a big swig of the beer, Shrink, slam the rest of the beer, NOW you're done.......
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