i guess you could use Tk::Menu::Item .

thus

use Tk::Menu::Item;
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and then use the -menuitems option for your menubutton.

eg.

$cardusagemenu->configure(menuitems => [
["radiobutton"=>"2M Sample Full Channel 333MHz 
Conventional", "-value"=>"2M Sample Full Channel 333MHz
Conventional","-variable"=>\$cardusagechoice], ETC. ETC.
])
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also, you might wanna have a look at : http://aspn.activestate.com/ASPN/docs/ActivePerl-5.6/site/lib/Tk/Item.html