Hi,
Is there a known issue on the R127, that when trying to use a digital servo say the Hitec 5945, it causes glitches. I have been told that if I upgrade to maybe an eight or nine channel futaba rx that the glitch may go away. He was suggesting that the R127 just couldn't handle digitals. Is this true? Thanks.

Adam

Hi Adam,

No that is not true, we use digitals all the time with the R127DF with no problems at all. If you have the R127DF and a digital servo and you are seeing glitching, it could be coming from a number of factors other than the receiver that is being used. Things such as long leads and high voltage could also be a cause.

Thanks, Krysta

Strange, well there are no long extensions, I am running a 6v battery (it happens more often on a 6v than a 4.8v), and the rest of the servos are standard. But whenever I put the digital in the whole thing starts to glitch. I would think it is just the servo, but it is effecting the entire setup so this leads me to think that it is the rx. I have tried on a few of my R127 and the same thing. any suggestions?

Adam,

I would bet it is the 6V battery then, if it seems to not happen with a 4.8V one. A lot of time you will notice this when there is a full load on the 6V battery, but as the voltage drops or a load is applied to the control surface it will go away. Again, we use digitals with our R127DF's all the time, and have had no adverse affects.

I hope you find this information helpful. You can also reach our Futaba support technical team at 217-398-8970, or via fax at 217-398-7721.

Sincerely,
Krysta
Lead Futaba Customer Service and Programming Technician

Well the thing is, it DOES happen with a 4.8v just not as much. I have had this issue on my airplane while flying on the first flight all the way to the 5 flight. (As soon as it happens on one flight, it continues the rest of the day.) Thanks.

Adam,

This may sound strange but I have run in to the same exact thing you are describing when I used that combination as well. Mine happened when doing dual aileron servos. I had to change the second servo to use channel 6 instead of channel 5 if I remember correctly and the problem was gone. I did this with multiple receivers, transmitters and servos all with the same results. Once I made the channel assignment change it went away.

Strange. What radio, I am running a 9cap. I may try to switch channels on it. Thanks

7CAP. I have a 14MZ now and have not tried it with that one to see if it is something strange between the transmitter and receiver. Let us know what you find out. I am curious too.

One thing to check. Do you get the glitching when you're using all Futaba servos? Sometimes, mixing brands can cause unplanned interactions.

No, I have a mixture of brands. Futaba and Hitec. I don't have any digital Futaba Servos to try though. I have a Hitec Micro, 1/4 Scale, and Digital High Torque. These are used with 4 s3004 servos for my ailerons of a Dave Patrick Ultimate. Thanks for the help so far.

Adam

What I was trying to say, is do you get the glitching if you only use Futaba servos? If you have a mix of brands, then you may be having a brand-compatibility issue. The only solution would be to use servos that didn't cause the glitching. It may be that the non-Futaba servos are causing some kind of feedback into the receiver that's causing your problem. If that's the fact, then your receiver's not the problem, but the non-Futaba servos would be.

Hmm, well what would be a comparable futaba servo to the Hitec 5945? And is it possible that only one of the servos are causing a bad interaction and the other two ( a micro and a 1/4 scale) are fine? Thanks.
Adam

Just updating this. I also noticed that the problem happened after I added a voltwatch. I never thought of trying to disconnect it. Has there been reports of any glitches being caused by voltwatches?

Yes, my friends plane had glitches and we all worked trying to fix it. I then asked him if he had added anything new to the aircraft and he said he had added a voltwatch. He disconnected it and goodbye glitches.

Copterdrvr

Well I have been able to recreate the glitch on two r127 rx and when I switched to the 138DP they went away. I am not sure if it is PCM helping here or if the 138 is just able to handle the digitals beter. But I flew without the voltwatch and it flew fine. I am also flying at a different field than usual. I guess the only way to be sure is to see if I could recreate this glitch on a 138DF. Any thoughts?

Hmmm. We haven't seen problems with the Voltwatch, but that doesn't mean that some might. We do know that NO Futaba servo that's working properly should cause any kind of glitching or erratic operation with ANY Futaba receiver. Any combination of Futaba servos on the same recevier should work without problems. Got glitching? Then something's not working right somewhere.

The Hobbico Voltwatch should not cause problems, either. It does do voltage sensing, but shouldn't interact with the rest of the system. It absorbs so little current that it should be nearly invisible to the servos and receiver. There's nothing in the unit to cause any kind of oscillation. The only failure modes we can think of would either make it inoperative (open), or cause faster battery drain (short or partial short). There's nothing to oscillate.

We'd need to see the unit that causes glitching when attached to a receiver and 'clean' when it's not.

There is one thread that mentions the voltwatch problem. I believe it is entitled Volwatch Troubles. Anyway, i think its more a servo or rx problem at this point. I think PCM may be masking it but I can't confirm till i have tried on a rx that runs ppm other than my 127's. My guess is that either the rx is unable to handle hitec digitals because of incompatibility or my hitec digital servo in particular is doing wierd things to the rx which is possible, such as feedback, etc. I will send in the servo before warranty runs out just in case. Could the feedback or something similar be the problem? I am a loyal futaba customer, and I just would like to solve the problem.