Lipo in 9CHPS?

[Pla]

Can I use 11.1V lipo to power 9C transmitter?

Is it advisable?

Also, since the lipo curve is different than NiCd/NiMH, is there danger the transmitter can shut off with very short or no warning?

Also, the built-in battery warning is set at 8.5V, can it be adjusted to 9.3V?

Thanks for any advise or opinion.

[BarracudaHockey]

Can you? Yes.

Would I? No. A 1650 NiMH that I paid 19 bucks for lasts all weekend and a few quick flights after dinner during the week and I dont have to worry about blowing up the garage charging it. I can only imagine how long the 2500's they are selling now last.

[Mangus]

Can you? Yes!
Should you? Up to you. Do you fly electrics with LiPos already? If so, why not go for it?

Advantages:

- Charging takes ~90 minutes at most
- Very long lasting (~8 hours w/ module until 9v minimum is hit)
- Can top off at any time (unlike NiCds)
- Very low self-discharge (as opposed to NiMH which require topping off after storage)

Disadvantages

- Charging is recommended outside the radio
- Charging dangers (mitigated by common sense and experience)
- LiPo charger needed
- Don't leave the Tx on by accident, since the cutoff is too low

Personally, I fly electrics that use LiPo anyway, so the negatives aren't substantial for me.

A good source:

http://home.comcast.net/~truerc/ready_pack/ready_packs.htm

(do a Ctrl + F search on "TX Pack")

No, you can't adjust the low voltage cutoff of the Tx without modifying the internals, which may or may not be possible. You'll have to be diligent about making sure the Tx is off and that you aboslutely shut the radio down at NO LOWER than 9v.

[Skiddz]

I run a 2700mah NiMh pack in my 9C.. It lasts 10-12 hours if I leave the Tx on, easily a couple weekends worth of normal use.

Takes a tick over an hour to charge at 2.7A..

[Pla]

Thanks for all the replies.

I already have 2 lipo chargers.
I liked lipo more because of the less weight and no self discharge. I could charge them with the balancing lead.

Do I have to remove them from the Tx even if I charge them with the balancing lead?

Or, I think I'll stick with NiMH so that my alarm still works and the discharge curve remains the same. The memory effect on NiMH is a lot less than NiCd so it doesn't concern me topping them off before flight.

[DavidH]

I would not charge LiPo's with them still in transmitter. I don't charge any type of battery with it still in the transmitter. Seen a few burned up transmitters due to battery meltdown in my years in the hobby.

David