keyboard implementation
Both hardware and software are needed for laptop and PCs.
1. Hardware
Below is an image that shows the stickers on the keyboard of a laptop.

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You can mark the new letters with paint or a marker on buttons,
(or)
Buy stickers from a printing shop. Below files can be used for printing:
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2. Software
2.1 For laptop and desktop (windows OS)
download the software AutoHotKey version 2.0 from below button and run (double click).
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2.1.1 For existing qwerty keyboard
download this remap_qwerty_123456_v7.ahk file and run (double click).
check and verify :

check if remapping is done :
Remapping of horizontal number pad to 6 important phonetics
1 2 3 4 5 6
ʌ æ ɔ ə θ ð
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when caps lock is on, then,
1 2 3 4 5 6
Ʌ Æ Ɔ Ə ϴ Đ
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You can exit the program by turning off in icons tray:

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