Zend certified PHP/Magento developer

PS/2 to USB converting for IBM Model M not working properly

I have an IBM Model M keyboard with terminal connector (similar to RJ45 socket) with model number 1394108.

I connected the wires to a PS/2 to USB converter like this images
enter image description here

It works but not correctly: when a key pressed one time (for example z key), it type that key code infinitely (zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz).
In the Other word, keydown works but keyup don’t work.

Is this problem from the converter or is related to keyboard?

How can I fix it?