Smith chart with SA44B/TG44A

[davorin]

Evnin'...

My Signalhound arrived this week and I'm currently thinking to get the tracking generator TG44A as well to get a network analyzer..

In an application note form Signalhound I saw that there is a feature called "smith chart" in their Spike software....
What actually is this tool useful for?

Can I use this with an injector to adjust an antenna design for a specific frequency?

[hendorog]

I have the SA124B + TG124A combo - which is basically the same as the SA44 series, apart from the extended frequency range.

The Spike software is quite new rewrite and doesn't have the Smith Chart feature (yet?)
That feature is in the older software which can still be downloaded and used on the same PC as Spike.

The other thing to note - in these devices the Smith chart feature works with a single frequency at a time. It doesn't sweep. This means a calibration is required for each frequency if you need to make measurements at many frequencies.

This isn't such a big problem for tuning antennas. You can sweep the return loss using the Spike software and a directional coupler. The Spike software works extremely well for this and is much faster than the old software.

Then make single frequency measurements and adjustments using the older software and the Smith Chart.

[davorin]

What sort of device is this directional coupler they are selling as well?

What is this small metal box doing for US$ 110? Or is this simple to be built selfmade?

[tggzzz]

Evnin'...

My Signalhound arrived this week and I'm currently thinking to get the tracking generator TG44A as well to get a network analyzer..

In an application note form Signalhound I saw that there is a feature called "smith chart" in their Spike software....
What actually is this tool useful for?

Can I use this with an injector to adjust an antenna design for a specific frequency?

You can find good explations here: lmgtfy.com/?q=smith+chart+antenna