Re: [Help]Extract S-Parameters: High Power Microwave Transis
Hello boy and sunn and all the others.
boy:
Yes, my idea was to try something like that, an l-match and maybe make different pcbs, etc....
Those guys producers of those tuners with computer control, software, all those builtiful sometimes useless things added....They must ask a lot of money. And probably they also make a lot too.... :')
sunn:
You really made thepoint. Yes, changing the position of the trimmers we gain another degree of freedom. I would say the position of the capacitor is making the impedance transformation from the very low output impedance of the transistor to the 50ohms at the output.
And the value of the trimmer is just what is needed to cancel the reactance at the point where it is. Very nice....
The impedance of the transistor will be measured with a network analyser I expect...
Do you know any good method to measure this so low impedance of the transistor output????
S:
ps:The transistor I have is an old ldmos, pushpull 150W output 28V drain voltage.....