[Elecraft] KX3 charger failure?

[Rich NE1EE]

I am missing a point:
Istvan said When I plug in the 13.8V PS the radio shows 13.8V for only 1 second and drops to 10.4V.
Don replied so the fact that the KX3 shows 0.3 to 0.4 volts lower than the external supply is normal.

Istvan said When batteries removed the voltage shown on display 13.8V.

I don't have a KX3, but I understand the diode issue..and it makes sense...but a drop from 13.8 to 10.4 doesn't seem right to me.

On 2020-10-08 18:56:+0200, István Szabó wrote:
>On Thu, 8 Oct 2020 at 15:58, Don Wilhelm <donwilh at embarqmail.com> wrote:
>
>> Istvan,
>
>> There are protective diodes in series with both the internal batteries
>> and the external supply, so the fact that the KX3 shows 0.3 to 0.4 volts
>> lower than the external supply is normal.
>
>> 73,
>> Don W3FPR
>
>> On 10/8/2020 2:53 AM, István Szabó wrote:
>> > When I plug in the 13.8V PS the radio shows 13.8V for only 1 second and
>> > drops to 10.4V. Eneloop batteries all OK 1.29V individually. Running a 4
>> > hour charging cycle it turns off when voltage reached and shows the
>> > dropped voltage. When batteries removed the voltage shown on display
>> 13.8V.
>> > Is it known failure, what can I do to fix it?