Howard, Yes that is true about the jacks on front but mine won't work on 
the outside jack with a paddle unless I ground the paddle to the chassis 
which makes four wires.  I thought it was my paddle but I have three of them 
and none work without the ground.  I think maybe on my rig that the ground 
of the jack has not been grounded inside the rig.  Thanks for your note.  Ed 
K7UC