Always irritated me that you cannot use favourite channels for a radio/tuner based activity on the Harmony One. Following advice from others I have a workaround that I believe would help others with the same device - Pure DRX-702 DAB tuner (701 uses same codes except 'Band' which doesn't exist on the 701).

I created a new Digital Set-top box as a VideoLogic DRX-702 and manually added in all the IR codes. Since this device type is thought to be TV based (and hence Logitech have allowed us to have Favourites), you can use this in a 'Play Music' activity by selecting 'cable/set-top box' and the activity will then allow you to set up the favourite channels.

It is my understanding that this device will now (or very soon) be in Logitech's database and accessible by others. In which case it should help others with either of these devices. Otherwise, you'll just have to create your own:-(

Truth is, we shouldn't have to jump through hoops in this way. Not allowing favourites for radio based activities is just plain DUMB.

I'm not sure I follow how you're doing your current workaround, but how about trying something like this:
Add new Device, Select Radio Tuner (or should it be TV?), for Manufacturer, pick -not listed-, then enter "custom" or something, then enter your model "DRX-702" or whatever. The review page will probably list the manufacturer as "AAA Generic". Teach your Harmony what it needs and see if you can still set Favorite channels.

A generic device will stay generic so you won't have to worry about them adding it eventually, as far as I understand.

I checked and it's not in the database (yet). It may never be if judged so by the Harmony database police.

exactly, that's a very good work around. we can't change the way harmony set it up and the constraints it puts on the remote usage but can certainly achieve certain goals with little hacks like this.

Note: You need to select a device type that is deemed to have a "TV" tuner like a TV, Cable/Satellite Set-top box, VCR, DVD recorder, etc. to enable the Favorite feature.

good point ... otherwise you'll be banging your head on the wall wondering why you can't set up the favorites.

Set up a non-existent TV, set its power and input commands to "none", set up a WatchTV Activity using it, specify the tuner to change channels, and you have the Activity you want with Favourite Channels.