rds8000 and 401

[rcgeek]

Has anyone had any problems setting up a 401 gyro with the rds8000?
And about how much gain have you had to put in?

First attempt tail had a bad drift to the left. Pretty sure it was set up right but maybe to much gain, then ran out of light. Been to cold to go out and mess with it since so I figured I would see what others with the 8000 and 401 have seen?

[TMoore]

Start your gain at 45% and -45%. These are usually good starting numbers for the RD8000.

[UBHSTRY]

I actually have my HH gain at 85% on my RDS8000, though I am running a clone 401.

[rcgeek]

OK, Thanks for the reply. I am at 50 and 50 right now, but I picked it up used so not sure it's good. Already ordered a 520.

[Farrell]

Make sure the revolution mixing is not causing you problems. Go to RU > RV.H, RV.M and RV.L. With a gyro like the 401 you do not want there to be any revolution mixing. Set all three points to zero, for all four flight modes (N, 1, 2 and 3.)

-Farrell

[zaw]

Yeah, on my RDS600 any new heli setting have some values in REVO settings by default. I too also have problem setting a gyro and that's how I found out.

[grawyl]

OMG!!! Thank you SOOOO MUCH! That was it! I have had this problem for ever and you fixed it!!!!

I have always had to induce a little trim to compensate but it was never quite right.

Farrel, Your the man!

TMoore - Why is the radio set to have some mix as a default?

[TMoore]

The RD Series was designed software wise in the late 90's and even the early Stylus radios from the mid 90's had Revo from the start because HH gyros weren't the norm. Sanwa never changed the prom burners and Revo mix was the default for these radios. It is really a legacy thing to be honest.

TM

[iceman320]

just wanted to know what are you guys using on the rds 8000 to get the tail servo from creeping? are you using the trim setting or the centering setting. cause i'm having problems with my tail servo wanting to creep on my exi 500. I'm using the align ds520 for my tail servo and I have the gy48v (401 clone) for a gyro. anyway any help would be great thanks.

[Farrell]

Neither. Trim or centering adjustments should not be used on any channel that has a gyro.

If your servo is creeping make sure nothing is affecting your rudder channel other than your rudder stick. No rev mixing, no custom mixes, no trim, no centering, etc. Plug your servo directly into ch4 and make sure when you move your sticks for throttle, elevator and aileron that your rudder servo does not move. Check it out in all four flight modes.

If your servo moves, you have some mixing enabled. If the servo does not creep at all when plugged in directly, you may need to adjust some settings in your gyro or the gyro itself could be bad.

-Farrell

[iceman320]

Farrell, my revo mixing is set to zero in all three flight modes. the only thing that i have is my d/r is set to 100% on the rudder channel and the epa is set to 150% on the rudder channel so should I set all those settings to zero also? could that be messing with the gyro? thanks in advance.

[Farrell]

DR and EPA settings would not cause the servo to creep, they will only affect your pirouette (spin or yaw) speed. Just try what I mentioned about plugging your rudder servo directly into ch4.

-Farrell

[TMoore]

On some gyros it is common to see creeping in HH on the bench. The gyro is looking to sense some piro rate and then wants to correct for it. In addition, some gyros don't learn the rudder center pulse on bootup. If that is the case, the simple fix is to run the gyro gain temporarily to 100%, switch to HH and then set the CENTER adjust on the rudder channel until the servo doesn't drift. Back the gyro gain down to normal settings once this is done, reboot the RX and check to see if the drift is gone. Most times the servo won't drift in rate mode.

TM

[iceman320]

well guys I took my 500 out today and the drift is still there. I will try to set the center pulse like you said then if that doesn't work I will plug my rudder servo into ch4 on my rx when I switch out bottom plates later this week. if nothing works or fixes this problem i will just forget about it for a couple of months and get my other projects done first then get a new gyro for the 500 like a spartan or a mini g. I have also been wondering if it could be my radio cause it seems like that ever since I got this stupid thing that I can't get any of the gyro's to hold on any of my helis. so could it be that something is wrong with my radio?

[grawyl]

Originally Posted by TMoore

On some gyros it is common to see creeping in HH on the bench. The gyro is looking to sense some piro rate and then wants to correct for it. In addition, some gyros don't learn the rudder center pulse on bootup. If that is the case, the simple fix is to run the gyro gain temporarily to 100%, switch to HH and then set the CENTER adjust on the rudder channel until the servo doesn't drift. Back the gyro gain down to normal settings once this is done, reboot the RX and check to see if the drift is gone. Most times the servo won't drift in rate mode.

TM

TMoore, I though that I had this drift issue fixed but it seems I do not. In HH, I get drift but in rate mode no drift (while flying). Can you please explain the steps above in more detail for me to understand?

Thanks

[grawyl]

Originally Posted by grawyl

TMoore, I though that I had this drift issue fixed but it seems I do not. In HH, I get drift but in rate mode no drift (while flying). Can you please explain the steps above in more detail for me to understand?

Thanks

In HH mode, should I be looking for the servo to stay centered unless the gyro (heli) is moved or will it tend to slowly turn to one side? Is this what you mean by drift? IF it is, would the followign procedure be the correct one to fix it?

With Heli on the bech;
1) Set TX to Norm flight mode
2) Set Gyro switch to Rate mode
3) Increase Gyro gain to 100%
4) Swith Gyro to HH mode
5) Adjust Rudder channel center possition untill the servo maintains center possiton
6) Reduce Gyro gain to previous settings (just below point of tail wag)
7) Unplug battery from ESC (and RX)
8) Connect battery to ESC (and RX)
9) Pray it fixed the issue

What does increasing the gain to 100% achieve? Does it send a command tothe gyro?

Thanks for your help?

[grawyl]

Well I went through the process listed above (if correct) and I still have the same issue. I am seeing the heli turn slowly to nose right in hh mode.

When I started out i set it up un rate mode and mechanically, it is sound and holds pretty good in rate mode but as soon as I switch to hh mode it starts to turn nose right. If I increase the gain any more I get a nasty bouce or wag after any rudder input. I have been able to get it to reduce this turning affect with some left rudder trim but depending upon heli orientation I still see it trying to turn right.

I am not sure if I got a bad gyro or its somthing in the radio.

please help.

Thx

[TMoore]

The 401 senses rudder channel neutral on bootup so adjusting the rudder trim with the gyro at 100% won't get you anything more than what you had in the beginning. Adjusting rudder trim only works on JR gyros.

Set the gains back to normal values.and make sure that the trim step in the radio is set to a value of 2 or less and try that.

TM

[grawyl]

I went back over it and I have the servo ctr and trim set to '0' and it does not drift in rate mode. Also on the bench the rud servo stays centered in both hh and rate mode. However while flying, the only way to keep it from turning nose right in hh mode is to use about 5 to 7 points of left trim (at 8 it starts to turn left). Like I said, it is fine in rate mode but as soon as I turn it to hh mode it starts to turn.

do you think it could be a temp change issue? The temp I have been flying in is about 35f and I have been taking the heli from inside the house which is about 65f. how long should I let the gyro acclimate to the outside temp? I am just trying to rule out all possibilities before I purchase a new gyro.

I really do appreaciate the help.

[TK5028]

From what I understand you need to let it sit out side for about 20 minutes before you fly.