I have 2 different models or radios - RT7 and RT 21. Can they talk to each other and how do I make this happen?

Yes,RT7 can talk with RT21. RT7 and RT21 are analog model radio,for analog radios communication, just set all communication channels with same frequency and CTCSS/DCS is ok. Please download USB universal driver and RT7,RT21 software from Retevis official website freely: https://www.retevis.com/resources-center. related video for your reference:https://youtu.be/PEDs3WkxjcM
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