my05monte

I accidently left my JR transmitter on the other day and now it does nothing. Tha supplied charger doesn't show a charge cycle nor do I get a reading on my voltmeter. Is the battery hopelessly gone??

dignlivn

How long did you charge it ?
What chemistry type ?
What type of charger ?


Bob

my05monte

I put the charger on for maybe 6 hours. I believe its a 9.6 nimh and the charger is the one supplied by jr

dignlivn

I would try charging it overnight.


Bob

Regent

My05,
I have seen this situation before for both TX and RX batteries. Some chargers require that it see some voltage on the pack before it will begin charging. This is how these chargers determine the number of cells present and what charge rate to use.

What I have done in the past is to remove the battery and place it across a basic 5V power supply for a few minutes. I use an old PC power supply and it does not have any intelligence, it just pumps out the current at approximately 5V and 12V. After a few minutes take a reading with your voltmeter and if the reading is around 4.5 to 5 volts on a RX pack or 8 to 9 volts on a TX pack then put it on the intelligent charger.

Discharging any battery down to zero does not do it any good. If the battery was in good shape to start with it will recover but will have decreased performance, and will be reduced something on the order of 1% to 2%. It could be more based on the battery chemistry and age.

Scar

My Feedback: (3)

I'm confused by your comment about the supplied charger. My JR came with a wall wart that just had a light that lit up (one for the transmitter, one for the receiver battery). Does yours have some type of "charge cycle indicator"?

If yours is like mine, with a small indicator light that just shows the charger is connected.... and it's not lighting up when you plug it in... you may have a blown fuse in the transmitter battery circuit. Or, you may still have the switch on.

If you're not getting any on-board voltage indication at all, that's another sign the fuse is blown.

Please, a bit more information.
Best wishes,
Dave Olson

goirish

You talk about not getting a reading on your voltmeter. Is the battery still in the TX. I have Futaba and I cannot use a voltmeter to check the battery when it is in the TX. Not sure JR is the same. I agree with SCAR. Make sure the TX is off. I know this is a dumb question, but is the circuit that you are using with you charger hot or does it have a blown fuse?

my05monte

scar yes it is the same charger with the lights. I took the battery out and used my dvm and paper clips and still no volts. Me thinks the battery bit the dust.

JohnBuckner

My Feedback: (1)

This is from your first post and not what you are saying in your later posts. Leaving a Tx on for extended periods of time it is possible for one or more cells to reverse polarity for all extents and purposes ruining the battery pack However your comments on what happened do not seem to gell. The very first thing I would do is to open the rear cf case of the Tx and visually check the fuse that all JR transmitters have. If ther fuse is open then replace and put the battery back in the tx and charge with your wall wort for 16 hours no less and no more.

Deadeye

Any chance it froze while discharged? That'll screw em up for sure.

flaminheli

Charge it for 15 to 16 hours and then check it.

j.duncker

My Feedback: (2)

The guys who say you need to "shock" it back to life are right. I would connect it in // with a 12 volt battery for a few minutes then try the wallwart again. Try that two or three times before discarding the battery.

However you should also cycle it before using it for real. Full 24 hour charge, then leave the tranny switched on aerial OUT for at least an hour and look at the the voltage or output meter. If it holds up for an hour then you have not done too much damage.

Recharge and go fly!

2slow2matter

My Feedback: (1)

Your JR radio should turn itself off before ruining the battery. It has a low voltage cut-off at around 8.3 volts, so there is no way you ruined your battery just by leaving the radio on. I'm not saying the battery isn't bad for some other reason, but the radio will guard against this....at least the modern computer radios will. What JR is it?

opjose

You're right!

I had forgotten about the auto-shutoff too.

He needs to check that when he plugs the charger in to the RX, that he is getting the light on the charger.

If not, then the circuit in the RX or the fuse may be fried.

He can check this by charging the battery pack outside the TX.... maybe on some other club member's charger.

If it works this way, then he can re-install it on the radio.

If the radio fails to power up, look to the fuse.

If the radio now works, but still refuses to charge, look at the charger itself it may be problematic.

Ideally try another charger and also check the continuity across the charge port to see if the input diode is fried.

If all else fails send it back to Hobby Services for repair. They are quite reasonably priced and usually turn things around within 2 weeks.

brett65

My Feedback: (18)

It's also possible to go below zero on a battery, atleast with an automobile battery. It usually means battery death too.

my05monte

Thanks for the help guys. Had a bad connection somewhere on the battery itself. now it shows 8.6 but if I turn the battery over in my hand it drops to 0. can you say hell-o garbage can

goirish

Good idea!!!!

opjose

How about "Hello soldering iron", instead?

Touch up all of the solder joints and I'll bet it will work.