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I have seen one case where "Stacking" transistors actually provided more output than a push/pull configuration and it was not used in a radio configuration.
It was used as a speed control for a DC motor.(FETs)
The maximums listed by Transistor manufacturers are just that. They are not holding back higher performance just to play with your emotions.
The energy lost in a combiner is not as much as you would think. If the transistors are properly matched and biased properly the loss would be negligible. There would be some power lost in DC resistance of the wire.
One thing I have not seen in this thread is the "De rating Curve." It figures heavily into the Junction Temperature" maximum. Heatsinks are forever changing temperature and the higher the temp the less power it can handle.
Also with the negative temperature coefficient the hotter it gets the more power it conducts and you end up in a thermal runaway. Lots of showy magic smoke coming out real quick.

<blockquote data-quote="Tallman" data-source="post: 676350" data-attributes="member: 32129">I have seen one case where &quot;Stacking&quot; transistors actually provided more output than a push/pull configuration and it was not used in a radio configuration.It was used as a speed control for a DC motor.(FETs)The maximums listed by Transistor manufacturers are just that. They are not holding back higher performance just to play with your emotions.The energy lost in a combiner is not as much as you would think. If the transistors are properly matched and biased properly the loss would be negligible. There would be some power lost in DC resistance of the wire.One thing I have not seen in this thread is the &quot;De rating Curve.&quot; It figures heavily into the Junction Temperature&quot; maximum. Heatsinks are forever changing temperature and the higher the temp the less power it can handle.Also with the negative temperature coefficient the hotter it gets the more power it conducts and you end up in a thermal runaway. Lots of showy magic smoke coming out real quick.</blockquote>

[QUOTE="Tallman, post: 676350, member: 32129"] I have seen one case where "Stacking" transistors actually provided more output than a push/pull configuration and it was not used in a radio configuration. It was used as a speed control for a DC motor.(FETs) The maximums listed by Transistor manufacturers are just that. They are not holding back higher performance just to play with your emotions. The energy lost in a combiner is not as much as you would think. If the transistors are properly matched and biased properly the loss would be negligible. There would be some power lost in DC resistance of the wire. One thing I have not seen in this thread is the "De rating Curve." It figures heavily into the Junction Temperature" maximum. Heatsinks are forever changing temperature and the higher the temp the less power it can handle. Also with the negative temperature coefficient the hotter it gets the more power it conducts and you end up in a thermal runaway. Lots of showy magic smoke coming out real quick. [/QUOTE]

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