wsmalley

My Feedback: (6)

I have a 1 meter sailboat with 2 channels, a Hitec 815BB on the sail and standard rudder servo. Hitec HP-2RNB Rx. El Cheapo Futaba Attack Sport (Ch 83)with 8 new batteries. I might add the crystals were a 'gimmee' from a fellow in the club so I don't know what they are. Yesterday, I took 2 charged 1000 mAH batteries to sail with my 5 or 6 sailing buddies. After about 15-20 minutes, the sail servo started going in and out, the boat would turn 'wheelies', a few seconds go by, I would get control back then, then 'Zap' started twitching again. Brought it in and swapped batteries, same thing, 15-20 minutes later- glitching all over again. Got home and checked the batteries, both read 4.6v (5.4 and 5.7v when I started)on my analog Hobbico meter. I have had this problem over and over, thinking my smaller battery pack was the problem, I brought out the 1000's! With my old boat, I could sail all afternoon on a 650 mAh-with an old Airtronics sail servo. Anyone have a clue what the problem might be?

redfox435cat

is there any binding in the current set up from lock to lock? Also from towers website on the servo.

This servo consumes 800mAh UNLOADED, Hitec states that it REQUIRES
a minimum of 1200mA receiver battery, 6V (5 cell) is STRONGLY
recommended.

So it would seem the servo is your problem

wsmalley

My Feedback: (6)

Hhhhmmmmmmmmm! Guess I should have checked that out! Thanks for the comment. It was quite windy yesterday so I guess it would have been pulling more. Raises an interesting question though: what exactly does it mean when you have a 1000 mAh battery and an 800mAh servo, or 1200 mAh, for that matter? Does it mean the servo could sit there without moving for an hour+ on a 1200 and 30, or so, minutes on a 550 mAh battery. Never did really understand that.

Electriceddie

Just in case your not aware:

Batteries when they die or are not charged enough will leave the servos in the last working position they were in. If it is eratic RF operation then they would be jumpy, so to speak. But it makes me wonder why the guy gave you the crystals. It also is concerning that you don't know what they are.



Good Luck

wsmalley

My Feedback: (6)

The servos were indeed 'jumpy' after the initial 15 minutes or so. The fellow who gave me the crystals had, in turn, been given a number of radios by folks getting out of the hobby, members and others who had died, etc. As to what make of radio they came from, neither he nor I know. But, if there is a problem with a crystal, Tx or Rx, why would they work for awhile with a charged battery. For that matter, would-or could- a heavy duty servo, run a battery down in 15-20 minutes? I've got a 1400 mAh battery in one of my planes, guess I'll give it a try! Perhaps I should have mentioned there are 5 or 6 other guys in close proximity sailing also-we race these things.

redfox435cat

the power rating of a battery is a current time base. 1000 mAh battery means when fully charged it can discharge at 1 amp for 1 hour. So that servo when just plugged in and doing nothing will draw .8A which would kill the battery in say an hour and 10 minutes. when you start using it it draws much more current. So 15 min would sound about right with normal use. at the same time 15 minute later since you've drawn the battery down your other channels are going to freak out since they have lost power.

With our planes we have 4-5 standard servos and will drain the radio in 20-30 min with a 650mAh battery since the entire system will draw about 2 amps under normal loads


Anyway I've been buying NiMh battery from these guys for a while and recommend them to anyone.
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