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Why do you use HV and / or why don't you?

Xpress

GSN Sponsor Tier 1
The irony is Hitec servos are the reason I have to use a regulator. Damn 7950's on the elevators and rudder won't stop dancing on HV so I had to add a regulator.:mad::oblong:

Are you using a Spektrum or JR receiver?
 

stangflyer

I like 'em "BIG"!
The irony is Hitec servos are the reason I have to use a regulator. Damn 7950's on the elevators and rudder won't stop dancing on HV so I had to add a regulator.:mad::oblong:
That is so odd to hear your 7950's are jittering. I have 7950's throughout the Sukhoi and not s wiggle one. Actually very whisper quiet. As for my 7980's on my 260? Again, smooth as silk, and whisper quiet. I have actually "tried" to get them to jitter. They just don't do it. Weird.....
 

stangflyer

I like 'em "BIG"!
Spektrum power safe 12 channel with Fromeco Li-Ions.
Don't know if this would help, but as I understand it, Hitec makes a "signal booster" to help with this. I actually have about ten of them I never used because my Hitec has been so crystal clear and the servos so very stable. Talk to @Xpress about the signal boosters.
 

Xpress

GSN Sponsor Tier 1
Spektrum power safe 12 channel with Fromeco Li-Ions.

The powersafe receivers for some reason always have this issue with long extensions going to the 79XX servos. We can send you signal boosters (for FREE!) that will ramp up the signal going to the servo and will cure the problem. Give us a call tomorrow and ask to speak with me (Tanner).
 

quadracer

100cc
To some extent Terry, you are correct. Most all rx's don't care "HOW" they are fed. But the biggest thing to remember, is to allow for a constant "UN-INTERRUPTED" power supply for the rx. I have read and seen some systems set up in such a way that servos were drawing power through the rx. and thus high demand from HV servos have been reported as drawing so much, that the rx itself "starves" for voltage. Dropping below the nominal 3.3 or so volts, causing brown out and complete loss failures. I know a lot of you out there don't use the SF boards, a lot of you have power safe rx. that allow battery redundancy. But the biggest reason I have used and continue to use the SF boards is because the SF powers up the rx to a constant 5 volts. With absolutely no risk of losing voltage, (unless the batteries are drained) And also allows battery redundancy for the rx. as well. While supplying a direct supplied voltage to each servo. Pluse with the SF boards, you also have internal battery matching and isolation features. As for using a regulator to utilize two lipos is a sound idea. Fromeco and SF both have some awesome regs. I have used both in the past. I think I like the Sahara from Fromeco best. I don't know Spektrum, but I would say if you are using a power safe version, You're covered except for the servos. You would need to find a way to regulate the servos to the 6.6 volts you are looking for. If you regulate the entire system, such as two regs, one to each battery connection on the power safe rx, then you are covered completely. And since you are not using HV serovs, you most definitely are not going to be starving the rx. for needed voltage. Unless you are considering a single reg that will give you the battery redundancy along with the battery matching and isolation features. Then in that case, You're set!!

I truly am a "HUGE" advocate of the SF boards. Battery redundancy, constant un-interrupted 5.0 volts to the rx., and battery redundancy of battery supplied voltage to my servos. If I were using a normal voltage servo system, I would go the route you are thinking.

These are just my thoughts. Maybe someone knows of a better way?
Spektrum receivers are good up to 9.6V, no reason to regulate rx voltage down to 5 (I don't know if you use Spektrum or not though..)
 

Terryscustom

640cc Uber Pimp
The powersafe receivers for some reason always have this issue with long extensions going to the 79XX servos. We can send you signal boosters (for FREE!) that will ramp up the signal going to the servo and will cure the problem. Give us a call tomorrow and ask to speak with me (Tanner).

@Xpress Can you ship an extra two for me with @ericb 's?? The 7950 on my 100cc Cap 580 rudder, that thing is CRAZY. I actually have to hold half rudder while starting because is shakes like crazy. Also the rudder on my sukhoi dances all over the place and that's in a 50cc bird with a standard spektrum RX and only a 36" lead.
 

Terryscustom

640cc Uber Pimp
Spektrum receivers are good up to 9.6V, no reason to regulate rx voltage down to 5 (I don't know if you use Spektrum or not though..)

Ahh, crap your missing the question. This is for a plane that has standard voltage, just changing battery technology only and looking to regulate to 6.6 volts.

Anyway, I got my answer after a couple hours on the phone with a couple of good friends here is what I am going to do:

1 - Buy one whole set of HV servos and run unregulated LiPo and power safe
2 - Set up one of my existing planes with Fromeco Ions, a Fromeco Reg and the power safe RX

This will allow me to compare all three battery technologies and mah consumption as well as flight performance difference. The problem I see is most people have only tried and are used to one thing. Therefore when they give advice it is bias to that setup.
 

yakken

100cc
The powersafe receivers for some reason always have this issue with long extensions going to the 79XX servos. We can send you signal boosters (for FREE!) that will ramp up the signal going to the servo and will cure the problem. Give us a call tomorrow and ask to speak with me (Tanner).
So do the hitec rx. The 7955 and 7950 servos all have had problems here. six different planes. They all jitter no matter what. We have tried signal boosters and diods.This is all on 35 to 40 centers. I have sent my 7955's back twice and they last maybe three flights before they start jittering.
 
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