NotTaR of Television Sets : TV blows fuses or trips breakers or wors..  
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TV blows fuses or trips breakers or worse when A/V connections are made

You have sent the TV for repair and now three times, it blows something the instant anything is connected to it in your house. Other A/V equipment operates fine.

Assuming all the other stuff is plugged into the same outlet asn is 115 VAC equipment and that thsi happens instantly when the TV is connected:

Next time they bring it back, measure the voltage between the A/V connector shields and the shields on your cables - I wouldn't be surprised to find some substantial fraction of 115 VAC between them. This would mean that there is an internal short in the TV (their problem - any competent service center will routinely check for signal-AC ground shorts) resulting in a connection between the non-isolated AC ground and the signal ground. When you connect your equipment, you complete a path which results in a short circuit. Depending on the design of the TV and where the fault lies, much more than a simple fuse may be destroyed. This is similar to connecting a scope probe ground to a live chassis TV - see the section: Safety guidelines.