Model: Motorola Talkabout 2-way radios
Typically you should be able to communicate by pressing the Push-to-Talk button (PTT). If it is necessary for you to press the musical note, you are using the Call Tone feature, which makes the other unit have a sound. This method is acceptable, but not necessary unless you want sound.
Here is a copy of the user guide: http://www.giantintl.com/RadioPDFs/Outdated%20Manuals/T56XX_57XX_User_Manual_E.pdf
Read the section on Call Tones and decide if this is the method you prefer. Otherwise, shut off the call tones and then you can simply use the PTT button to communicate.
You are correct, the radios must be set to the same Frequency. Plus, they must be on the same Code (interference eliminator code) and the Qt filter must be set the same on both units. Following setting everything to match one another your radios are ready to communicate.
Best regards. Read More At : Talkabout T5720 (7 Channels) 2-Way Radio...