RichLoop

Anyone know why after years of running two steering servos, all of a sudden they glitch and chatter? Have replaced radio, and servos, but still no change while both are connected.

All Day Dan

My Feedback: (5)

Disconnect all other servos. Make sure your receiver battery is good by measuring it's voltage with a voltmeter loaded to .5 amps. Plug the battery directly into the receiver. Plug the servos back in to the receiver one at a time. What's happening? Dan. dan

RichLoop

Did all that, one single servo works, but is not strong enough for the monster tires. For years, twin servos worked great, all of a sudden, they chatter unless I unplug one or the other.

RichLoop

Have Replaced servos, tried a different radio and receiver, same results.

dirtybird

My Feedback: (5)

you were lucky before to have two evenly matched servos. As you are now finding that is not always the case.
The cheapest way to fix it is put the servos on separate channels that are mixed together. Then play with the trim and sub trim until you eliminate the chatter.
They used to sell a device that you could plug in up to 4 servos on one channel and individually adjust each servo to eliminate them from fighting each other when connected in parallel

RichLoop

What is this device? I have a spare channel but have no clue how to marry them.

TFF

http://www.horizonhobby.com/product/...system-jrpa900

RichLoop

Thanks for the info. So I am clear before buying this, Both servos will work with each other? Great news. Thanks again.

cessnaflyer54

My Feedback: (68)

There is a little device that the airplane guys use to match servos went they have multi servos on one wing. It is a lot cheaper than a JR matchbox. If I wasn't having a brain fart right now I could tell what it's called.

ltc

My Feedback: (3)

Depending on which radio you have, you can use the radio's built in servo matching capability; thus avoiding the cost of a Matchbox.

SWORDSN

My Feedback: (13)

Has anyone used a Life battery with a matchbox? It's rated for 6volts.Will 6+ volts damage it?

cessnaflyer54

My Feedback: (68)

I'm using a LiFe battery with a matchbox. I have four servos for flaps hooked up to the matchbox and
have had no problems so far. Could let you know more after next weekend as I will heading to WOTR.
Will be the maiden flight for my new plane and the set up.

SWORDSN

My Feedback: (13)

Thanks,please do

All Day Dan

My Feedback: (5)

Send an email to the manufacture of the match box to get the right answer if their electronics that is designed for six volts will survive 6.6 volts. No one else is qualified to make such an important decision. Dan.

ltc

My Feedback: (3)

If you are concerned about running the Matchbox on a LiFe battery, you can simply put a diode in series to drop some voltage down to 6V or install a small inline BEC (voltage regulator) to get 6V output.

6V rated servos and electronics came about years ago due to a 4 cell Nixx pack approaching 6V under full charge/no load. The pack voltage would quickly drop down close to 4.8
However, people started assuming that 6V meant that they could use a 5 cell (Nixx) pack (since 5*1.2=6V); however a 6 cell Nixx pack would be well over 6V under full charge/no load conditions until the cells dropped down closer to 1.2V each.

That having been said, there are lots of people running 6V servos on a 6.6V LiFe cell for years with no issues reported.
But if you want to live by the letter of the law, put a diode in series or a BEC.

pilotpete2

The major servo brands provide speed and torque values at the nominal voltages of the batteries they're designed to be used with, so a servo with a 6V rating has to be able to handle at least 7V for a fully charged 5 cell Nixx battery. There are very few servos being sold today that aren't capable of 5 cell nixx or 2S LiFe operation.
Pete

All Day Dan

My Feedback: (5)

Good discussion Pete. You fail to take into account the initial charge voltage of a five cell battery pack is above six volts for a short period of time. A 2S pack is at 6.6 volts continuously. That is a big difference because regulators within the servos or receiver are not designed for that. They will overheat and eventually fail. Like I said, check with the manufacturer first. Dan.

SWORDSN

My Feedback: (13)

You are right,but mfg usually hedge and are slow to respond.I think it will handle 6.6,but i hope someone has experience.Thanks all for your response.

pilotpete2

OK, a 600mAh Nicd with a 200mA load will take a full 15 minutes to drop to 6.6V. So the servos and receivers internal regulator better be able to deal with 6.6V, as well as the almost 7 volts they see with a 5 cell pack fresh off charge.
I've been running 6.6V LiFe for 7 years now on a wide variety of servos with 6V speed and torque ratings, no problems. I have been buying all HV rated servos lately though. The Hitech HS-430's are a real nice dual BB HV servo for about 13 bucks.
Pete