[PARAPTOR]

Originally Posted by Steve S

K the batteries are brand new, there's no problems unplugging the shore hydro and running everything off of 12 volt.
I swapped the cables from one TV to the other and still no changes.
I'm 100% sure this isn't a 110 issues as that just wouldn't make sense.
I'm thinking that maybe, just maybe that the main TV just doesn't get enough signal but then again how does turning things on affect the signal?
As mentioned above about the inverter, if this is hay wired is there an easy way to test it?

Stick with me a moment, want to make sure we are on the same page: To start I have no idea where this "inverter" came from? I see no reference to it in your original post, so I am going to ignore it in this post assuming there is none. I am going to assume you are following John's procedure, ie disconnect shore power and run an extension cord from the house to power the one 120VAC TV (strange one). NOW:

From what you are saying all is fine (everything working normal) after disconnecting shore power. To Summarize no 120VAC to trailer other than extension cord to power one TV, 12VDC solely being supplied by the onboard batteries. Electric portion of HWT out of the picture as well as the Converter has been taken out of the picture, everything else the same such as coaxial and battery connections. In this state as you said all working fine. Electric portion of HWT can not influence anything its off, on propane only if selected.

Here is what I would do to try and isolate the problem:

Switch off the 120VAC breakers to the WHT and Converter then reconnect back to the Shore Power leaving TV connected to extension cord to house. I would expect all to be working fine as before. Then if all working fine I would power TV into trailer 120VAC source. Again if all still working fine I would introduce say the converter by turning the breaker on, check everything for awhile, if okay sometime later introduce the electric portion of the WH by switching its breaker on.

This would be my suggested approach