tacan to vor, can't find out how it works

[thenikos]

hi everybody, i follow the instructions of the manual to get a vor freq working in tacan configuration. i want to insert the 108.60 vor freq, the manual says that i should put the number 23.
the procedure i follow is:

1. switch on the vhf radio and put it at the tr+g position.
2. IFF at the norm position
3. tacan mode to R/X position
4. tacan freq at 023.
5. X/Y switch on X.
   i suppose that when the vor is in range, the green arrow should point at it. but it never happens as i fly around the airport.
   what did i do wrong? or what did i forget to switch on?
   thank you !!