Change encoding of txt file

You can use iconv to convert the encoding of the file:

iconv -f ascii -t utf16 file2.txt > another.txt

another.txt should then have the desired encoding.

You could also try this:

echo $var | iconv -f ascii -t utf16 > "file2.txt"

Use iconv:

echo "$var" | iconv --from-code=utf-8 --to-code=utf-16le --output=file2.txt