Magicdude

Is it normal for a throttle digital servo to make the analog servo working the elevator jump around? Are the two compatable? I'm using a 72mh Futaba TX with a Seeker 6 RX on a combat plane. I've substitued another RX and replaced the digital servo with another digital and the elevator still jerks around. Everything works fine using only analog servos. Do I need to use only analog servos?

nute12

My Feedback: (14)

i have never been quite sure of this myself, but i have run a digital rudder servo on my dp ultimate with the rest analog for a long time and never had a problem. i am currently building a 100cc extra have the radio installed, running all digital metal gear servos on the surfaces and a analog metal gear on the throttle. no problems are apparent. i am using a futaba 9c super 72 mhz
I think i would check that ele servo.

A.T.

Under normal circumstances, providing that the digital and analogue servos are not on same RXinput channel via a "Y" or similar, then there is no problem. However, if the digital is on to thin an extension lead* or there is a long extension to the elevator servo, these can cause problems. Digital servos must be connected with HD, prefereably twisted, extension leads and are more prone to problems withbad connections~ or batteries.
*.To obtain the high standing torque and quick response, digital servos require more from the power source than standard servos. Use heavy duty harnesses, anda larger capacity battery to ensure proper servo performance.
~. Mixed brand of plugs - some after market/other brandlook similar and tight but can be a loose fit on pins, even new name brand leadshave proven faulty.

See also sub Section "Glitches & Jitter in Receiver, Servo & ESC - causes and cures " under
"Radio Systems, Accessories, Alterations and FAQ." at:
Alan's Hobby, Model & RC FAQ Web Links

Regards
Alan T.

BarracudaHockey

My Feedback: (11)

What does twisting leads do?

Thats a loaded question, the answer is nothing

A.T.

Perhaps you are correct and I have no argument, but with respect, this reader/user defers toaknown servo design tech's comments and as published:
Hitec Catalogue 2010 - Page 11 Servo History and Technology Achievements. - extract attached.

Alan T.

nute12

My Feedback: (14)

I heard the twisted wire was for rf noise also, but,did you get the increased wire size from 22 gauge to 24 gauge? I cant be gettin that old. The bigger the gauge number the smaller the wire is what i was always taught.

A.T.

Goodtypo pick up.. "Hitec servo use 24 & 22 guage.
Copy old post Servo - (Lead) Wire gauge

The other question I have is what wire gauge to get?
<snip></snip>Much depends upon length and voltage drop, refer to
"Servo - alterations, calculators, databases, repairs, convert to an ESC or winch & FAQ" at
Alan's Hobby, Model & RC FAQ Web Links
Twisted wire leads were added to many of the Hitec servos in 2002 in an effort to prevent RF noise from long servo leads feeding back into the servo causing unnecessary servo "jitter". High power digital and analog servos need plenty of current to deliver massive power. Recognizing this, Hitec increased the size of the wires from 24 to 22 gauge to provide the power these servos need to perform at the highest level. Hitec items which may assist:
#54651 is a light weight 160 mm servo wire with plug for micro servos.
#54652 is a light weight 160 mm servo wire with Female "S" Connector.
above 2 items can be soldered together to make a lightweight extension lead of up to 315 mm, long lengths are not available.
#57417 is a standard weigth 50'(15.2m) length of 24 gauge servo lead.
#54804 is a heavy duty 50'(15.2m) length of 20 gauge servo lead.
Servo lead connector leads and fittings - differences"

Another good independant reference:
Servo Extentions and Jitter - JR.

Alan T.

BarracudaHockey

My Feedback: (11)

Twisting works great on preventing cross talk between communication pairs that are running in the same bundle. The pairs are twisted at different rates.

Since servo wires only have power and ground next to the signal wire, twisting doesn't do anything IMO (and I taught network cabling at the local University)

Rodney

BarracudaHockey is correct, twisting the wires on servo leads does nothing to prevent noise or interference in the way a servo is wired. it does make for a neat installation though.

dirtybird

My Feedback: (5)

It also creates a happy feeling to some individuals, also

BarracudaHockey

My Feedback: (11)

True, you can never underestimate the "warm and fuzzy"

Servowires

I'd have to agree as well on the "Twisted gives a Warm and Fuzzy". I've been selling Servo Extensions for years now. I offer both normal ribbon and twisted extensions and whenever I'm asked if twisted wire does anything for RC applications, my normal answer is that it just looks good. The warm and fuzzy must work for a lot of people because I sell more twisted than flat extensions.

Alan_UH

HIV Titanium gear servos,high torque and high speed for rc cars,helicopters and airplane Click here

tomfiorentino

You kill me...