Todays "Fun with TE": news on the distributed amplifier!
Half-way build picture, with capacitors to ground vertically inside the pcb
![Evil >:D](https://www.eevblog.com/forum/Smileys/default/xevil.gif.pagespeed.ic.tdrs7Uj5gu.png)
Idea was to reduce parasitics and required space. Turns out an 0603 fits pretty nice inside a 1.1mm hole. Bugger to solder tho.
![](https://i.imgur.com/cTiFOgu.jpeg)
Finished build, with and without gain pot. Gate 2 decoupling and connection bodged on with kapton tape and wire (aka poor man's triple layer pcb):
![](https://i.imgur.com/O0h0ozE.jpeg)
Measured with the Nanovna V2+
![DMM :-DMM](https://www.eevblog.com/forum/Smileys/default/smiliey_dmm.gif)
red=gain
blue=input return loss:
![](https://i.imgur.com/5zG22uY.png)
red=reverse isolation
blue=output return loss:
![](https://i.imgur.com/u4GDIae.png)
~5.5dB gain and gain flatness is not too impressive
but P1db at about 10mW/10dBm and 25dB isolation worst case (courtesy of the cascode nature of dual gate mosfets) make me happy nonetheless
![Grin ;D](https://www.eevblog.com/forum/Smileys/default/xgrin.gif.pagespeed.ic.QVVz6XIT20.png)
Not sure though why the gain goes up towards higher frequencies
![Confused :-//](https://www.eevblog.com/forum/Smileys/default/confused0024.gif.pagespeed.ce.5xOqKkq0Co.gif)
Schematic for the one's playing at home:
![](https://i.imgur.com/03sFCa5.png)