CATsync & RFI

Overcome reception problems by using WebSDR / KiwiSDR ?

I had high levels of noise because of plasma televisions/RFI. I will give you a good solution which helped me through several QSO’s by using an online KiwiSDR.

You will need 3 programs and a ham radio with COM or USB port. First you need preferrably Ham Radio deLuxe, secondly you need a com port splitter, and you need program called Catsync.

What is Catsync?
CATSync is a program that allows you to syncronize public WebSDR receivers with your rig connected via CAT control to your computer. It supports the classical WebSDR as well as Kiwi SDR interfaces. It simply imports the KiwiSDR browser page into the catsync program and through Omnirig you change the RX frequency of the KiwiSDR. The frequency is the same as the frequency of your transceiver. When you listen to the output of the computer you will hear the audio from the kiwi. At the end of this page you’ll find a youtube film showing you how it looks like.

There are many KiwiSDR and WebSDR online. There might be one in your neighborhood? It has to be nearby. Check it out here or on a map.
Catsync is a great program, and costs only $9.95. The program you get from here:

Option 1: How to run Ham Radio DeLuxe simultaneously with Catsync?
You need to split the available com port from your transceiver so you can tune frequency both Catsync and HRD AT THE SAME TIME. This you do with a virtual serial port splitter.

You can try VPSE from Eterlogic. This works fine, but there are better alternatives, more smootly. You can start this program for free with an annoying message every time you start up the program. Price 25 us dollars.

I use TCP Com Bridge from Aggsoft and costs you 50 dollars, for me this program works more smootly.

So now you split the com port of your ham radio. The newly created two virtual com ports will serve both Catsync and HRD.

Option 2: You can use Catsync together with Log4OM. Log4OM is like ham radio deluxe, a logging program. Both programs use Omnirig and you do not need a com port splitter.

What I did was mixing the AUDIO output from the transceiver and the AUDIO output from computer through an external hardware audio mixer. This way I could listen both to the hamradio and to Catsyncs output simultaneously. I did that by using a cheap audio mixer bought on So when signal reception QRM occurs at home, I can mix the audio received through Catsync, and hopefully finish my QSO.

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