Tired of AA's...

[J57ltr]

Originally Posted by nitrostarter

Just got off the phone with Traxxas on this issue. He said he was never asked that question before and he was discussing it with another guy there. The best he could say was it's around 10v. I told him I was trying to see when at what voltage the light started blinking so that I could possibly use that as a LVC. He actually suggested the smart thing in saying to get a LVC for 3s and be safe that way.

So Jeff, if you wouldn't mind trying to see at which voltage it will start to blink that would be nice. I would like to know as well. My cells have internal cut offs tho.

I'll set it up on my power supply tonight and watch the voltage with my Fluke and give it a few tries and see. I have a TQ3 and a friend has a TQ2, can't imagine that they would be different, but I'll do it anyway.

Jeff

[zeropointbug]

I would guess around 9.0 - 9.5 volts the TQ3/2 would blink at, maybe 10.0volts. I can't even remember what my DX2 alarms at... I think it's 9.1 volts?

[redshift]

I was guessing <9V, out of curiosity I just used a 9V out of a smoke detector, at 8.6V on my DX3.0, no alarm. But we know that a DX7 has one because it woke him up one night when he left it on. He doesn't remmber the voltage it was reading tho. And the Nixx are hardwired on the DX7, and he wants to know before he clips the lead..... told him he was gonna have to put a jst connector on anyway- but he's friggin stubborn.

[bdebde]

Originally Posted by zeropointbug

I would guess around 9.0 - 9.5 volts the TQ3/2 would blink at, maybe 10.0volts. I can't even remember what my DX2 alarms at... I think it's 9.1 volts?

DX2 is probably the same as my DX3... 9.0 volts... chirps like a cricket, lol.

[rootar]

my dx3s goes nuts if you leave it on the voltage drops down, i has the same battery compartment as the dx3r so im thinking why cant we get a 2s lipo thatll fit in there and run the ccbec set on 5.5 volts and then even close to the lvc its would still be supplying .5 volts more than the bec is putting out..... you can get a novak blinking LVC and mount it ontop of the base and just wire your on of swtich BEFORE the lvc and bec

so youd have the lipo, plug, switch, lvc in parrell, and then the ccbec before it goes to the radio power leads .....

did i confuse anyone else or just me?

honestly i use the energizer lithium AAs and they last for 6 months getting used every weekend alot...

[zeropointbug]

Yeah, but how much do those primary Lithium AA cost again? $12 for 4? You can see that it wouldn't be long before a rechargeable transmitter pack would pay for itself, one year maybe. I would also get a LiFe pack, as weight is not a concern, plus it will last a decade at the very least running something as low powered as a radio.

[J57ltr]

OK, date with the wife got in the way of testing, but here are my results. This is in the TQ3 I have, have to wait till John comes back over to see what a TQ2 will do, but I don't expect any difference except for normal manufacturing tolerances.

At 8.03V the light starts to flash.
At 4.2V it starts to dim while flashing.
At 3.353V it's really dim and still flashing.
At anything under 3.25V it completely shuts off.

To test this I had to use an old Protoboard with built in power supply 0-15V. The meter I used is a Fluke 112. I did both rising and falling voltage to test hysteresis 3 times.

Jeff

do these cell phone battery not need to be balanced?

[J57ltr]

They should be they are just like any other Lo-po/Lo-ion, and now they are made into a pack, and they came from different devices that probably had different charge/discharge cycles. The ones I am using are from the same laptop pack and they are out of sink by up to a 1/4V, that's why I put a balance plug on mine. I also have a ton (about 50) of the Fat/Long aa size Li/ions and they act the same way in packs. No 2 cells are alike.

Jeff

[zeropointbug]

Okay, I have had my DX2.0 running for 16 hours now, and the voltage is still at 12.7volts... there must be a voltage regulator in there.

[zeropointbug]

Whow, right after I typed that out, the voltage fell to 12.6volts.

[J57ltr]

I wonder if it just sits idle unless the reciever is also on, kinda like a sleep mode?

Jeff

[zeropointbug]

No, I don't think it does... when I used AA alkalines, you turn the switch on, then after a 2 second pause, the LED on the back lights up and the voltage suddenly drops. It must draw a good amount of power.

[nitrostarter]

I took the Summit out today and the cell phone batteries worked flawlessly in the Tx. Awesome! Let see how long they last on 1 charge now....

[zeropointbug]

What is the mah and voltage on that pack?