Impedance matching using resistors

[neazoi]

Hello I have this circuit **broken link removed**
If I am not wrong, it seems that it tries to lower the output impedance to 50 Ohm using a combination of resistors. Is this technique correct? (let's ignore power loss from the resistor for the time being)

 

[VSMVDD]

why bother the low z output is 56ohm balanced with a 560R input

if the input to the 560R is 10v p-p then the 56R will have a Z of .96 to 1

due to the velocity factor

so youll have 50R at the low Z out as is load balanced

and hi z i think is more like 560-56R relative is is 496 parts of 10v

so replace the 560R and the 56R with a 100R and a 1K variable

problem solved
just peek the variable if you present a dummy load @50R

peek both pots for max foward power with min refected

its a no brainer....

56R load res * 1.404 = impedance ~78R

so work from that to 33R instead...