This helps many portable shortwave radios. You can be intuitive in your method of execution to obtain some more reception. This is not going to perform miracles. It is a well known fact in shortwave radios that if there is too little of a ground path or little reactive capacitance the radio is limited to what the antenna can hear. So to try to overcome this we make sure we have two same lengths of wire. Not necessarily full wave lengths of wire. Modern portables do have hotter front end reception but not enough reactive capacitance. I demonstrated in video:
