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December 02, 2020, 02:32:36 am

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Radio Battery for IC Models

Started by meharibear, June 21, 2020, 15:41:10 pm

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meharibear

The long absences from flight has me thinking about replacing some of the 4 and 5 cell NiCads/NiMh etc powering my radio systems before returning to flight.  Rather than just like for like replacements I was wondering about LiPo/LiOn replacements and a voltage regulator alternative which I know some people use.  Any advice and recommendations?  And those of you who have gone down the Lithium route any advice on brands/types/suppliers?
Inside every old person is a young person wondering what happened.  (Terry Pratchett)

FrankS

I did dabble in using Lipos and a UBEC but couldn't see the point of adding another device in the system, but have been using 2s LiFe packs as the voltage is basically a direct replacement for 5 cell Nimh pack.

But may in future look at using HV servos and 2s Lipos.

British Victory

I've gone over completely to LiFe cells, tbh it's a nobrainer. This includes receivers, transmitters and glo drivers.
The only gotcha I've suffered is with some old JR servos which, after checking at wee macgregor, proved to be for 4 cell nicads only.
It's virtually impossible to get the smoke back into them no matter how hard you try.
I won't recommend the following procedure but if you lose a model and later recover it, obviously there will be 0 volts on the battery.
A few seconds, literally, on a NiMH cycle will bring the volts up over 4 ish and it can then be recharged as per normal.
The battery that I did this on took almost exactly the capacity on the sticker and has been in use, without charging, for the last year powering my servo checker.
there's only one f in RCMF,
               John

FrankS

Quote from: British Victory on June 22, 2020, 06:55:43 amI won't recommend the following procedure but if you lose a model and later recover it, obviously there will be 0 volts on the battery.


Or if you leave it switched on in the shed/garage...............

RobC

Just as a point of interest and definitely not a recommendation, I have run JR 5xx (517 or 519s maybe) servos on 2S LiFe in a 120 FS powered sports model (a Dragon Lady) amongst others over the last several years.  I simply didn't know not to when I set the model up that way, maybe the servos didn't know either?  More likely they weren't being stressed to their maximum rated load so it simply wasn't an issue.
As for brand, I have a mix of Turnigy and Zippy from HK.
flying's easy - it's getting it back down in one piece that's the hard part

British Victory

Rob, my JR servos dated from 1983 or 84 when I built a Southerner major, a couple went duff virtually immediately when I changed from nicad to LiFe about 2009ish so I looked up the servo database and it said that they were for 4.8 volts only can't remember their number now but JR are so expensive that I only use futaba, hitec, corona and turnigy now and I've never had any problems. I also have some J Perkins servos that stand up to the voltage ok but the centering  leaves much to be desired so I don't use them anymore.
there's only one f in RCMF,
               John

RobC

I must admit that when I discovered that JR only rate their servos for 4 cell Nixx I stopped installing them in IC models. Now that I've got rid of everything IC I've started using my old stocks of them again on BECs though I've also still got stocks of Savox and Spektrum DS821 digitals and Futaba analogues from the IC models that I sold off.
Corona and Turnigy have proved totally reliable for me too, even in petrol models.  In fact the last servo failure I had was a wiring failure inside a Futaba 148!
flying's easy - it's getting it back down in one piece that's the hard part