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Several RPTVs produced around 2003-2004 apparently suffer from the same failure. A convergence amplifier chip tends to burn out, causing one or more of the colors to go out of convergence. (i.e. All the red is suddenly an inch to the left of where it should be.) The repair is pretty simple, but shouldn't be considered if you don't know what you're doing near high voltages (30,000 volts, etc). The problem chip is the STK392 series. The two in my TV are pictured above. I purchased a pair of STK392-110s from electronix.com for $5.99 each. Several people reccomend using a higer power rated version - I didn't feel like reading data sheets, so I went with original spec'd hardware.

To repair my set, I removed the back of the TV, labelled the three matching wires shown next to the STK, and got familiar with the rest of them. I gently disconnected the jumper connectors that crossed to the power board, and removed the entire PC board with the STK392s.
On my workbench, I removed the heatsink screws and used a cheap desoldering iron to de-solder the STK392s. Once they were loose, I used a soldering iron to release any stuck pens and pulled the old chips clear.
While the chips were out, I used a multi-meter to check all of the large resistors to make sure nothing burned out. All of them checked out, so all I needed were the new STK392s.
To finish up, I inserted the new chips and screwed them to the heat sinks. Once they were mounted, I soldered the pins and cleaned up the resin residue with some alcohol and a q-tip.
Once the board was re-installed, I powered up the TV and was able to converge the display using the usual consuer menu. (Panasonic has fine convergence in the service menu, but it's difficult to do without the service manual.)
Last Modified 10/6/12 01:28