CATsync & RFI

How to overcome RFI problems? – UPDATED 15/2/2021

Well, I had these problems! I had high levels of noise because of plasma televisions and other RFI. I will give you a quite good solution which helped me finishing many QSO’s without missing too much. This I do by using online SDRs.

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.

Catsync has a waterfall view which allows you to see where the stations are over a wide spectrum.

There are many KiwiSDR and WebSDR online. There might be one in your neighborhood? Best to have one nearby. Check it out here or on a map

But how to get this thing working?

Alternative 1: When using Ham Radio Deluxe, you need 3 programs and a ham radio with COM or USB port. First you need Ham Radio deLuxe, secondly you need a com port splitter, and you need program called Catsync.

Alternative 2: When using logbook program Log4om version 2 (free logbook), you only need two programs. Log4om version 2 & Catsync. Both programs use Omni Rig for cat control and you can skip a com splitter. Configure OmniRig and you are good to go and you can use both program simultaneously. Easy!

Catsync is a great program, and costs only $9.95. Have a look at it, Youtube link: The program you get from here:

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.  

Looking for a Virtual Serial Port Splitter?

You can test VPSE from Eterlogic. I had some problems with this program, but I got it finally working fine. You create just 1 virtual port and use the same virtual port on both Catsync and HRD. Costs about 25 us dollars.

Otherwise TCP Com Bridge from Aggsoft. It will cost you 50 us dollars and you can try it out for two weeks for free. With this you create 2 virtual ports, one for Catsync and the other HRD.

So from now on you can split the com port of your ham radio.

Catsync and Log4OM use both Omnirig. You do not need a port splitter when using these two programs.

I suggest you set in Omnirig Poll int, ms to 100 and timeout, ms to 100 as well to get the fastest results. You should configure your radio on the first Omnirig tab: Rig 1.

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 ham radio 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.