Problem when entering Russian letters in the console?

Question

linux

I have a NAS QNAP TS210 I
connect to its ssh (openssh) using putty (UTF-8) or ssh client in xubuntu.
I can’t enter Russian letters in the console (/bin/sh) (although some are partially entered, but I can’t go to the “Russian” folder, for example).
1) If you open mc, then everything is well entered from the keyboard and there are no problems.
2) All letters are displayed correctly and there are no bugs.
3) When copying / pasting Russian letters, there are also no problems.
With all this, it is impossible to enter Russian letters from the keyboard.
Tell me what could be the matter and where to pick it up ?!
I understand that something is wrong with sh, but how to fix it ?!
/bin/sh --version
GNU bash, version 3.2.0(163)-release (arm-none-linux-gnueabi)
Copyright (C) 2005 Free Software Foundation, Inc.
LANG and LC_ALL = ru_RU.UTF-8 (en_EN.UTF-8)

Answer 1

Those support said

The fact is that initially it is not supposed that work will be done on the command line.
Qnap NAS is a piece of software and hardware, not pure Linux.
Also, from the correspondence with technical support, we can conclude that the problem is on ARM devices, everything works fine on x86.

Answer 2

It seems to be related to the convert-meta parameter in bash (I have it enabled). I can't turn it off. set convert-meta off doesn't work. Also adding it to /etc/inputrc does not work.

Answer 3

Try to select UTF-8 encoding in the connection settings in the Translations menu, if you haven't done it already.

Answer 4

Maybe it's in Putty,
look that in
[HKEY_CURRENT_USER\Software\SimonTatham\PuTTY\Sessions\<name of your saved session>
I have
"LineCodePage"=""
"CJKAmbigWide"=dword:00000000
everything is displayed fine, but
in the session
with
"LineCodePage "="UTF-8" " CJKAmbigWide
"=dword:00000001