EMRFD Message Archive 11951

Message Date From Subject
11951 2015-12-06 16:14:50 Rod KST data plotting for filter sweeps
Hi All,

There is a very powerful data plotting program called KST. It is
available for Windows and Linux.
It offers a wide array of data visualization tools.

I have uploaded a zip file of some crystal filter sweeps using KST
software, called filter-pix.zip.
It is worth taking a look at those pix.

The data was generated by a homebrew scalar network analyzer and sent
over a serial link
to the PC for logging. A companion program on the PC put the data into
KST friendly files.
Then I manually ran KST to create the plots you see.

The impetus for this project was that I wanted to improve my homebrew
crystal filters, and
had no method of accurately recording filter sweeps. I needed to record
them for the purpose of comparing filter "improvements", so I built the
hardware and the software to do so.

The homebrew scalar network analyzer (SNA) is an Arduino running an
AD9850 DDS,
and a W7ZOI power meter circuit feeding analog into the Arduino, which
the data and sends it on a serial port to the PC.

If there is some interest, I will release the software under a GNU
license, along with
hardware notes. If one has the skills to build a high performance
receiver, one certainly
has the skills required to build the SNA. It is actually a lot easier
than building a high-perf
receiver. And all of it was done with discrete parts and .1 inch center ICs.

I hope you take a moment to look at the plots- they will give you an
idea of what can be done.
(BTW- the gobbledy-gook on the Hz scale below is on the to-do list of
things to fix!)

11952 2015-12-06 22:34:04 Ashhar Farhan Re: KST data plotting for filter sweeps
i have written a fairly usable program for windows that does sweeps. it can be adapted to any sweeper or spectrum analyzer with minimum effort. you can get the source code from https://github.com/afarhan/specan-ui and you can see it working athttps://www.youtube.com/watch?v=dkQTSFjqY5k

- f