I have set up a Galvanic cell and used filter paper that is soaked in KCl as salt bridge. The electrolyte I used is 1M and the experiment is carried out in room temperature. However, I am unable to obtain the standard cell potential. The voltage values I obtained was lower. I was thinking maybe the salt bridge is not good enough, so I added more filter paper strips. The voltage did increase, but I thought the salt bridge should not affect the results? Is it impossible to obtain the standard cell potential? Could it be the resistance of the voltmeter? Thanks!