model yachting Australia - including d'12metre radio yacht forums

Hi folks,

Now that I am more back into the sailing bit, I thought I might just say a few words about receiver battery packs...

Okay, nearly all servo's are capable of handling 4.8 or 6.0 volt NiMh batteries. There are some specialised servo's that will only handle 4.8v, but they are few and far between. And these are all analog servo's.

If you're moving to digital servo's because of their increased accuracy, then they will probably, quite happily handle 6.0 or 7.4 volt LiPo or even the much heavier 7.2v NiMh batteries, if they are needed, to get your model up to minimum weight specifications. 

However, whilst the digital servo's are mostly happy to accept the 7.4 v continued voltage, analog servos will only accept that level of voltage for a short time before they burn out, unless they are using NiMH batteries.

NiMh batteries, are only in the high 7 volt range for a short while, but their power decreases with use, so the servo's are not that strained. But I talk about rated 6 volt packs here, because when fully charged they will nudge, or even slightly exceed the 7 volt level.

But 7.4v LiPo's are different. They are for a start, very much lighter. They will also hold their power until they are almost discharged, and analog servo's are not designed to take that amount of power, over the many hours that the LiPo batteries  are capable of providing, and as a result, the servo's may burn out very quickly.

So how do we cope with this? How do we cope with this increasing trend of replacing our faithful NiMH batteries with the higher power LiPo's?

We either replace our existing analog servo's with digital servo's, which seems a waste if the analog's are working fine, or, pay a lot more money and replace them with digital servo's, or, get a voltage regulator!

I personally have chosen to go with the voltage regulator option.

Why? Because my analog servo's are in perfect working condition, and, the cost of a voltage regulator, is much cheaper than replacing my analog servo's with digital ones. Voltage regulator's that you can switch between 5 of 6 volts output are available from the USA fully imported at a cost of around $30.

But, you are blessed if you have an RMG winch installed in your boat, in which case, no further outlay at all is required, as the winch will handle the 7.4v input with ease, and only pump out the 4,5, or 6 colts, needed by the receiver.

I hope this has helped, but please do not hesitate to post questions if you need more info!