Every time I turn my panasonic T V on it blows a fuse. What can be causing this problem?

A fuse blows when the circuit is drawing more current than the fuse is rated for. It's a safety feature to keep you from burning down your house. If this is a circuit breaker, it's possible that the circuit breaker is worn out. You can test that out by plugging the TV into a different circuit. If it blows a fuse again, then something in the TV has burned out, causing the TV to overload the circuit.

There are literally hundreds of possible causes.

Many possibilities. Would start with the Verticle and Horizontal outputs, the larger transistors.
Check for a short in place, then remove transistor to verify it is not elsewhere on the board.

Wait a second. Is the TV blowing a fuse inside the set, or is it actually tripping one of your house's circuit breakers? Fuse blowing or tripping a breaker is probably a problem right at the front of the power supply, not a bad horizontal or vertical output transistor. Most TVs now use a switching power supply that feeds the horizontal and vertical deflection circuits, as well as providing a low-voltage 'standby' supply that is always on and allows for your on-off circuit and saving settings, etc. The horizontal deflection circuit, in turn, provides the rest of the set's operating voltages (this is called a 'scan-derived' supply). If the horizontal output transistor or other component shorts, you will have a dead set, but probably not a blown fuse. You might also hear a high-pitched 'screeching' noise coming from the power supply indicating it's being loaded down. The blown fuse suggests something right at the front of the power supply, like a shorted rectifier, filter capacitor, or switching transistor. MAJOR SAFETY WARNING: This front side of the power supply is often called the 'hot' side because the common ('ground') connections in this section are connected directly to one side of the AC line. DO NOT try doing anything to this area with the set plugged in. This portion of the power supply (primary circuit) may be marked to indicate that it is the 'hot' section.