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Everything you wanted to know about VarAC and were afraid to ask

Who is behind VarAC?

My name is Irad Deutsch, 4Z1AC.

I'm an amateur radio operator since the age of 13 (30 years now). I was always fascinated by digital modes such as PACKET RADIO, AMTOR, PACTOR, GTOR, CLOVER, FT8/4, PSK and others... and love chatting using those modes rather then just exchanging reports. 

When VARA emerged into our lives I adopted it as in my opinion it provides the protocol robustness of PACTOR coupled with the ability to handle challenging SNR levels like FT8. So I have decided to create a chat application with lots of cool features to chat with my fellow hams.

But I am not alone. There is a great team of supporters and testers that play a major role in this project. You can read more about them here.

I am in touch with VARA creator (EA5HVK) about feature requests and bug fixes, but I have NO business relations with him. I am doing this purely for fun.

What operating systems are supported by VarAC?

VarAC is written in C# which means it runs on Windows as-is. But many are using it on Linux using the WINE platform. Read more about this HERE.

How can I find people to chat with using VarAC?

EASY :) our main QRG is 14.105.00 USB dial. Simply tune your transceiver and hit the "CALL CQ" button. If someone is monitoring the frequency, they will see you on screen and even hear a DING sound.

If you want to make yourself visible to others - you can also activate a beacon by clicking the "SEND BEACON" checkbox so once someone tunes in, they can see you and connect with you.

You can also join our vibrant Facebook community and schedule a QSO by posting there. There are plenty of people who will be happy to assist.

What RIGs are supported by VarAC?

VarAC needs to manage your PTT. In addition it is recommended that it also manage your RIG frequency. Therefore it requires CAT control of some kind (unless you chose to use VOX which is not recommended).

You can use both direct CAT control, RTS/DTR for PTT, and I made your life easier by integrating with OmniRig which covers every transceiver out there.

Can I monitor VarAC QSOs of others?

Sure! Go to VarAC settings --> VARA Modem Configuration --> VARA-HF Monitor (Optional)
Click the small (?) icon for more details.

500Hz or 2300Hz ? which one should I chose?

Well, we want to be efficient. So by default all VarAC QSOs are made in 500Hz. if you want to test a wider bandwidth, feel free to do so but pick another frequency which is not in the listed VarAC QRGs, and play. Just be respectful to other hams on the band.

Does VarAC keep track of all QSOs?

Yes. VarAC records all QSOs in an ADIF file. In addition VarAC can send UDP/TCP broadcasts of QSO entries to most of the leading QSO loggers out there. Click HERE for more information.

What are the limitations of using VarAC beacons

Beacons are great. But they can also become a nightmare for your fellow hams. So I have incorporated a few limits:

  • Beacons will be automatically disabled after 24 hours.

  • Minimum beacon period is 15 minutes.

  • Beacons will not be fired if the freq is identified as BUSY with ongoing VARA QSO or other beacons/CQ calls. IT waits for 60 seconds from the moment the frequency is cleared before sending a beacon.

  • Beacons will not be fired while you are in a middle of a QSO/CQ even if Enabled. In other words - you don't need to disable beacons while Chatting or CQ-ing. It will continue to beacon once you end your CQ/Chat.

My OmniRig has a delay in transmitting

In OmniRig - set the "Timeout, ms" menu item to "100" and you are good to go.

What can I do if I encounter a bug in VarAC?

Yes. Bugs and crashes may happen. And I am willing to work fast to resolve them. but I need your help by providing these details.

Simply log in to the VarAC community and file your bug here. Please provide as much information as you can including: 

  • A bug description and how to reproduce

  • A screenshot

  • The VarAC.ini file

  • The VarAC.log file

  • The relevant section of  VarAC_traffic.log file

What are VarAC prerequisites?

to read the full list of VarAC prerequisites list, click HERE.

Are VarAC and Vara-Chat compatible ?

Yes but up to a certain level.
VarAC can connect Vara-Chat and conduct a healthy QSO. However VarAC has many unique and proprietary features that will not be decoded on Vara-chat such as Emojis, Sounds, Is typing etc...

Where can I find VarAC manuals?

There are still no official manuals as every thing is very new. But some brave VarAC users decided to invest their precious time and write manuals. You can find them all HERE.

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