Also for the Travcos that had the 50 amp receptacle in the rear toolbox for the shore power plug, It really depended on what generator you have. ex:
I am running a 4k Onan 120v 1ph. So I have the two hot bonded but if you were to plug a 50 amp cord into that 50 amp receptacle say to power a house, you would not be getting 2 110 hots, just one.
If you have the 6k onan with the extra rings, It produces 220 volts and is wired correctly so that the 50 receptacle in the storage cmpt could be used to power a house with true 220.
1975 Travco 270
1974 Travco 220 Parts unit