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TNT-1500 problems

Yes, I think it´s an imbalance cause I measured the current of the 4 pairs and it´s all the same so the TR´s might be ok.
Bad combiners perhaps?
 
When a combiner resistor smokes one stage is producing more power than the other,this is what causes the resistor to get hot. you have 2 100 ohm resistors on the combiners where the 2 transistor stages are being tied together,which one of these is getting hot? also check your 10 ohm swamping resistors on bases of all transistors.
 
There are 3 output combiners. 2 for the 4 pairs and behind the 2 combiners and the last one is getting hot. You see it on the pictures were the coil is soldered.
 

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