I am using arc 300 trying to link radio freq with this software
Not sure what you mean by "link radio freq", but judging from your previous posts in this thread, I'm going to guess that you are still asking about "importing" frequencies from Radio Reference into ARC300.
If you open the help file that comes with ARC300, (from the menu bar at the top, click "Help", then click "Open Software Manual"), and look at Chapter 3. There are very detailed instructions there on how to use the "Import" feature of the software to access the data at Radio Reference.
After reading those instructions, go back to the top tool bar, click on "Internet, then click on "Radio Reference Import".
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