W1GHZ wideband LDMOS amplifier

[geggi1]

I have been looking into the broadband linear amplifier by Paul Wade W1GHZ.
The nice thing with tis design is tat it seams to be matched by the feedback ciruit.
I'm considering to use the BLP9LA25S from Ampleon  because it is reasonable priced at Digikey.

Does anybody got any experience with this design?

http://www.w1ghz.org/small_proj/Simple_Broadband_Power_Amplifiers.pdf?fbclid=IwAR3YgBK0XcMjm8Pf7RvfS0K1sAYcKH0kOPxq88wlrE-OUwmS_qzDBEkwM8s

[RFDx]

I have been looking into the broadband linear amplifier by Paul Wade W1GHZ.
The nice thing with tis design is tat it seams to be matched by the feedback ciruit.
I'm considering to use the BLP9LA25S from Ampleon  because it is reasonable priced at Digikey.

If you are looking for straight 50 Ohm IO impedance then you are limited to certain gm values. The BLP9LA25S has at 100mA almost 1S which makes the gain with a 50 Ohm load very high and the amp prone to instability. The max. output power in class-A would be, depending on the voltage of the power supply, relatively low compared to what the LDMOS can achieve. To get more output power and bandwidth you have to go down with the impedance and put some broadband transformers at in- and output.

[LaserSteve]

Paul Wade had a tray of the transistors ĥe used and kindly sold me a pair.  If you choose the right type of feedback resistor, it works well.

My gain numbers are somewhat lower then his, but I never saw any inherent oscillation. 

Yes, The design works.