Battery not fully charging Vbar touch

Hi, My transmitter batteries would only charge to 90% so I changed them for new and they still only charge to 90%, is this a problem with the onboard charging circuit? I have tried my JETI charger and that doesn’t seem to make a difference.
Is this a problem or do I just accept that 90% is all I’m going to get from now on?
Thanks in advance for any advice

Lets narrow it down:

If you charge the batts unless surely full with the Mikado wall plug (anothe rwall plug won't change anything, the "Charger" is on the PCB inside), then open the VBC w/o turning on, measure the voltage of the battery, then turn on and measure while running again.

Would be nice to see if you have a multimeter - but be careful not to shorten the battery or others inside.

How many Volts in this 2 cases?

regards (EN) / Gruss (DE)

Rainer Vetter

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Thanks for the quick response Rainer.
I have done as you asked and have 4.207 on both batteries when off and drops to 4.196 when switched on. I would assume from this that the battery is at full charge.
Would the drop to 4.196 bring it down to 90% or is the battery indicator wrong?
After being on for 3-4 minutes I turned it off and the voltage sprung back to 4.206.
Regards
John

Okay - thanks. I'll charge and measure mine tomorrow evening.

regards (EN) / Gruss (DE)

Rainer Vetter

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Posting and answering - please use a PC and a standard keyboard. Answer all questions fully, take the needed time, don't forget probably requested attachments.

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Thanks Rainer

My values for my VBar Control touch, some years already in use are:

Single Battery, original 4000mAh:
End of Charge, Radio off: 4.20V
Radio on then: 4.17...4.18V
Display: 91..92%

Dual Batteries, original 2x4000mAh:
End of Charge, Radio off: 4.20V
Radio on then: 4.18...4,19V
Display: 94..95%

So - the 4.2 Volts is w/o any load as 100%. But this will never been shown because adding load (turning on the radio) it drops down a few points to 4.17 ... 4.19V depending ob brightness, number of batteries, capacity and age of them. Quiet a normal behaviour here.

Now adding some measurement tolerances of a few % - it might happen you see around 90-92% only even if fully charged turning on the radio.

Knowing this - nothing to be worry about as long as the battery is ok. A weak battery will show faster % drops at all - even if starting from 90%.

regards (EN) / Gruss (DE)

Rainer Vetter

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Posting and answering - please use a PC and a standard keyboard. Answer all questions fully, take the needed time, don't forget probably requested attachments.

Für Posts und Antworten bitte einen PC und eine richtige Taststaur benutzen sowie alle Fragen vollständig abarbeiten. Nehmt Euch Zeit, beantwortet Rückfragen in Ruhe und vollständig.
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Edited 1 time(s). Last edit at 04/15/2023 10:38AM by RV.

That's great Rainer thanks for that very thorough explanation. As the batteries are new I'm sure that I haven't got a problem there, I can see where you're coming from and it makes sense to see a drop in voltage when powering on but I have been getting 100% for the last two years after charging that's what through me.
I think I overreacted a bit by buying new batteries but I don't know the history of the old ones as I bought the radio second hand, so the batteries was the first thing to suspect. As the old saying goes I'll keep an eye on them! Thanks again you've been very helpful with your thorough testing.
Regards John