Chris Lupa Key Veteran Location: Sonning, Reading UK
Hey guys,
thinking of buying some JR 8717 servos and running them with an unregulated 2 cell LiPo like some of the big guns have been doing recently. I know the spektrum stuff is rated up to 9.6volts, but the Futaba ones are "rated" at 4.8 - 6v. On paper it's not a good idea to run the higher voltage pack BUT my guess is that it will be fine as there is no motor to burn out (like on servos) and I've heard most receivers can take very high voltages. Will the R607FS receiver be ok with the 7.4 - 8+volt voltage?
raptorheli2 Elite Veteran Location: rip off britain and no changing it
i asked futaba this question directly and was told no chance. 6v only, but others run a123's on them in big planes......i would buy a reactor from sgp if you want to run 8717's
Chris Lupa Key Veteran Location: Sonning, Reading UK
Thanks for the responses guys. Looks like I'll run a Reactor if I want over 6V to the servos. Shame that Futaba's "latest and greatest" receivers can't handle the voltage taken by the up and comming 7.4v servos
Chris Lupa Key Veteran Location: Sonning, Reading UK
That's awesome news Still considering if I should risk it. A 7.4V battery charged is going to kick out over 8V and I don't want to fry my receiver! hmmmmm....might have to get in contact with Bobby Watts and ask him his experiance.
raptorheli2 Elite Veteran Location: rip off britain and no changing it
just a quick one here on another thought.
i have 8717 servos and i have tried them at both 6 and full charge 2s voltage. flying wise if there is a difference i can't tell. both voltages i tried i was able to crack easily and both had the same snap. what i'm getting at is altough it would be clean to run direct from a 2s battery for performance it isn't needed. so you could run the entire system happily at 6-7v's so long as your tail servo/gyro/thro servo could handle it.
QuickSilver Veteran Location: Cherry Hill, New Jersey
Higher voltagesFinally I found someone who shares my same thought on this issue. Does anyone really need the extra voltage? Not only that can anyone honestly say they can tell the difference between someone running 6v VS 8v? I couldn't tell, and if you believe otherwise your only kidding yourself. Unless you level of flying has gotten to a point where every little bit of performance will give you that extra edge I see no reason not to just stick with 6 volts. Just MHO.
Take care
Kyle
Life is not measured by the number of breaths we take, but by the moments that take our breath away.
It's not that I need the extra voltage.....it's that I want to run lipo's for their high capacity/weight ratio and their lack of auto discharge over time.
Putting a regulator in the system is just one more thing to fail, so I would rather do without them if possible. It seems they could just make it so that we could use a 2 cell lipo without a regulator. Is that too much to ask???? (I guess it is!)
05-02-2008 02:41 AM
QuickSilver Veteran Location: Cherry Hill, New Jersey
voltageWell if that is what you want to do then go spectrum. From what I understand they have a receiver comming out that can handle 9.6 votls and its a govoner, regulator and step down for the tail all rolled up into one compact package. What I dont understand is how is it they can make a helicopter speed controler that can handle 14.4 volts but not a Rx? Whats the deal?
Kyle
Life is not measured by the number of breaths we take, but by the moments that take our breath away.
Still considering if I should risk it. A 7.4V battery charged is going to kick out over 8V and I don't want to fry my receiver! hmmmmm....might have to get in contact with Bobby Watts and ask him his experiance.
Does anyone really need the extra voltage? Not only that can anyone honestly say they can tell the difference between someone running 6v VS 8v? I couldn't tell, and if you believe otherwise your only kidding yourself. Unless you level of flying has gotten to a point where every little bit of performance will give you that extra edge I see no reason not to just stick with 6 volts. Just MHO.
