This is the SC of my cable WITH the attenuator in the middle of it This is the SC of my taken apart coaxial cable WITHOUT the attenuator
My questions are as follows: What is a Smith chart and how do I use it to improve my attenuator+cable design? Is this a feasible method for creating basic fixed RF attenuators given that they don't need to be super accurate and only need to function over a very specific range of frequencies (905-920 ish MHz)? Basically I took apart a coaxial cable and hand soldered in some close-to-calculated carbon 5% resistors in between the two SMA connector ends. Now I should mention that my prototype is very shotty. However, the smith chart is all over the place when I measure S11. I have prototyped one using just off the shelf resistors in a T-pad configuration that gives me a decent level of attenuation (pretty flat 19dB) when I perform an S21 measurement using my network analyzer. I need a few different levels of attenuation but each different attenuator can be fixed. I'm working on designing some hopefully simple RF (912 MHz) attenuators.
