Author Topic: RX batteries...  (Read 18854 times)

Fred

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« Reply #15 on: July 05, 2010, 19:09:03 PM »
Hi Aidan,


You can go for the Low self discharge ones, will work great, but as Nando said, why not Lipos ?
Converted my Evo a year or 2 ago, and will never go back to Nimh for TX ! (all my radios are Lipos now).
2S lipo, no diode, and charge the battery.. Once every 4 to 6 months in my case for the evo  :D  And that's intensive use!
Flew everyday in Britany for 2 weeks last month, the reading on the charge only lost 0.4v  :D  Bringing it in Germany tomorrow, still haven't charged it.

I have photos if you are interrested, but really no tricks, really easy to change over  :D

Otherwise, I can bring you a few "Carrefour" ones, I think there is a Carrefour in Cherbourg  :D
Education is important, but flying RC planes and gliders is importanter!

Aidan

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« Reply #16 on: July 05, 2010, 19:54:56 PM »
Quote from: "Fred"
Hi Aidan,


You can go for the Low self discharge ones, will work great, but as Nando said, why not Lipos ?
Converted my Evo a year or 2 ago, and will never go back to Nimh for TX ! (all my radios are Lipos now).
2S lipo, no diode, and charge the battery.. Once every 4 to 6 months in my case for the evo  :D  And that's intensive use!
Flew everyday in Britany for 2 weeks last month, the reading on the charge only lost 0.4v  :D  Bringing it in Germany tomorrow, still haven't charged it.

I have photos if you are interrested, but really no tricks, really easy to change over  :D

Otherwise, I can bring you a few "Carrefour" ones, I think there is a Carrefour in Cherbourg  :D

I don't see a major advantage in lipos for the transmitter. I had thought about it but If I was going with lipos I'd probably use cells between about 2000mAh and 2500mAh anyway so I'm not gaining much in capacity. Self discharge would have been the main incentive for me to use lipos but the LSD NiMH cells seem to cover that angle pretty well.
I sometimes leave a glider and transmitter in the car just in case of good weather on the way home from work. I'd be happier with NiMH sitting in a hot car than lipo. I know the risk is tiny but without a convincing advantage for lipo I'd err on the side of caution and simplicity and use Eneloops or these other LSD NiMH cells.

Is there something else that I'm missing?

Aidan

P.S. Perhaps I could use a small space saving - I'm trying to fit in both the Jeti module and EVO 35MHz module with a switch and there's not much extra space in a Royal EVO!

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« Reply #17 on: July 05, 2010, 19:55:40 PM »
I’m surprised that you‘ve  used a 2S li-po to run a Rx Fred. :shock:  A fully charges 2S Li-po = 8.4v. With a rx designed for a nominal 4.8v I’d have thought the Li-po would have damaged it. :? Or are your rx's 6v ones?

The only thing that puts me off using Lipos for Rx is the fact that in the event of a crash landing, (Which I’m very good at), I fear that the Lipo will burst into flames. :(
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billscottni

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« Reply #18 on: July 05, 2010, 19:58:53 PM »
TX Keith!!

Happy Days

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« Reply #19 on: July 05, 2010, 20:26:09 PM »
OOOoooppppsss! :roll:

My Tx operates on 9.5v so I assumed they were talking about rx radios.

I’ll just walk off somewhere and dissapear down a crack in the floor! :oops:
Try not to run out of airspeed, altitude and ideas....... all at the same time.

billscottni

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« Reply #20 on: July 05, 2010, 21:22:10 PM »
But good radios ie MULTIPLEX run on 6 cells/7.2v :twisted:  :twisted:

Fred

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« Reply #21 on: July 05, 2010, 21:28:38 PM »
Hi Aidan,

True ! I went directly from Nimh to lipos, but never went the LSD route for my TX, I think mainly because soldering 6 or 8 cells end to end, is a bit of a challenge for me (and also the known issues with the Evo to blow up the HF when doing "fast" charging!).
For my RX, I found that much easier to do.

For the Evo, there is very little space! If interrested, I think I still have the 2 nimh packs I had, one relatively new for the Evo   :D  Just need the plug at the end (cut it from your dead pack).
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Aidan

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« Reply #22 on: July 05, 2010, 22:47:34 PM »
Quote from: "Fred"
Hi Aidan,

True ! I went directly from Nimh to lipos, but never went the LSD route for my TX, I think mainly because soldering 6 or 8 cells end to end, is a bit of a challenge for me (and also the known issues with the Evo to blow up the HF when doing "fast" charging!).
For my RX, I found that much easier to do.

For the Evo, there is very little space! If interrested, I think I still have the 2 nimh packs I had, one relatively new for the Evo   :D  Just need the plug at the end (cut it from your dead pack).

Yeah, I haven't tried soldering end to end yet but how tricky can it be  :?:
I do have a hammerhead soldering tip I got years ago but never used so that should give me a reasonable chance at success. I'll practice on some old cells and see how it goes. As long as I can keep it to no more than a couple of seconds contact the cells should be okay.

Thanks for the offer of your packs but I presume they're 4 or 5 cells per pack and I'd rather not combine cells of different ages and histories. Do you know if Aldi routinely have these or if it's likely to be a hunt? I'll drop in to the local one tomorrow and take a look.

Aidan