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I noticed C14, the input padding cap to the 8 transistor section, has been removed. That suggests that the input impedance to this stage, is below 50 ohms and cannot be "dialed in" by adding any capacitance. To confirm this theory, look at the turns ratio used on the RF transformers. They are the same for the driver stage as they are in the final. In fact, it seems every Rocket box regardless of size, uses the same turns ratio in every stage.

Assuming the driver is at 50 ohms, using the same turns ratio with 4 of the same stages combined, results in a 12.5 ohm impedance. While I can't read the value of the other padding caps used here, they should not be the only change made to compensate for this much of a difference in impedance. That could also be the reason we see little more than 12db of overall gain, including the driver stage.

[QUOTE="Shockwave, post: 740313, member: 10882"] I noticed C14, the input padding cap to the 8 transistor section, has been removed. That suggests that the input impedance to this stage, is below 50 ohms and cannot be "dialed in" by adding any capacitance. To confirm this theory, look at the turns ratio used on the RF transformers. They are the same for the driver stage as they are in the final. In fact, it seems every Rocket box regardless of size, uses the same turns ratio in every stage. Assuming the driver is at 50 ohms, using the same turns ratio with 4 of the same stages combined, results in a 12.5 ohm impedance. While I can't read the value of the other padding caps used here, they should not be the only change made to compensate for this much of a difference in impedance. That could also be the reason we see little more than 12db of overall gain, including the driver stage. [/QUOTE]

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