Question: For a normal 5 watt handy working in VHF or UHF freq with 50 ohm antenna , is it possible to use a same length coax cable instead of a stub antenna, so as to work like a crude antenna. Will this only result in extra capacitance/ VSWR damaging the system ?

Answer: 
youtube has a video of a piece of coax with the last 19" being separated between the center, pulling it out of the sheath. poor mans dipole. seemed to work
<http://bit.ly/2scIYD7>
Grid dip the coax to quarter wave, then put half wave wire on the center conductor end. Should work fine but clunky. Why not buy one of the longer antennas made for walkies?