You need to limit to the maximum power you decide on ?with an attenuator on the input and either accept lower on other bands or change attenuators each time
ps. The input impedance is far from 50 ohm resistive so attenuators behave strangely and the dB reductions is less that the stated value ?mostly due to high impedance on their output side
This higher PA input voltage (more EMF than PD) actually inflates the ¡®measured¡¯ gain figure (e.g. from about 22dB on 10m to the 24 or 26 quoted)?
(on the two I¡¯ve built anyway )
Moral. ?Build it and see rather than do calculations on flawed assumptions?
Other comments. ? ?
Starts to distort above 5W on 13V supply so LPF¡¯s definitely needed if using similar voltages?
Care needed on heat sinking. ? The supplied insulating washers for the PA transistors are a tiny bit too long - perfectionists can countersink the case /heatsink slightly ?to avoid just squashing them when trying to tighten the screw and risking less pressure over time?
Bruce Akhurst