Large Model Association Forum

What is the best method of reducing voltage from Lipos to operate 6v servos?

My Multiplex receiver will work on 7.4v with no problem, but I have dozens of Hitec 645 servos which have a max capacity of 6v. Is there a good proprietary system available to sort out the problem?

Thanks for any help

Peter Maw
LMA 3034

Hi,
I run all my planes on 2 cell LiPo's. There are 2 main types of voltage 'regulator'.

The most common is a 'ubec' or an 'sbec'. Both of these are an electronic switching circuit that essentially switches he supply onand off very quickly, regualting the speed to maintain the required voltage. These can be prone to a noise issue because of the high frquency switching - I used to have noise issues with these when using 35meg but no problems though now I use 2.4.

The other type of regulator is sometimes called a 'linear' regulator or 'non switching. This type loses the excess voltage through a power transistor that converts it to heat. hence you will often see a heta sink attached to these.

All my planes are electric and since the main flight batteries can now and again have a cell failure, causing a dead-stick, it is very sensible to have a seperate battery for the receiver/servos. Rather embarassingly last weekend I was flying a plane and as it came out of a stall turn the flight pack battery fell out and parted company with the plane!!! Hence a dead-stick, saved by the seperate 1000mah battery.

Have a look on HobbyKing, there are 30 different types. I can let you know which ones work well if you like.
Cheers
Andy

Hi Andy

Thanks for the info.

As you say their is a bewildering display on Hobbyking. I want to use 2S 3amp Lipos on most of my planes so which devices do you think work well as there is also a large variety of comments about most of the units

cheers

Peter

This is my favourite linear high current unti http://www.hobbyking.com/hobbyking/stor ... oduct=6313
I use 2 of these on dual power supplies for Spektrum AR9100 on my bigger models.

These are my favourite switching units
http://www.hobbyking.com/hobbyking/stor ... oduct=4319
http://www.hobbyking.com/hobbyking/stor ... oduct=6233

I have had no problems with any of these.
Cheers
Andy