Thank you. He is trained to return on three beeps of the whistle. I guess my use of the tone/vibrate would be more of a "you're ranging too far out; time to check in and wait up." Almost more of a warning that, if he continues to range out, I'll have to apply pressure.
I trained my lab the same way. Started with voice commands. Then overlayed to a whiste. 1 whistle meant sit/stop, look at me. 3 whistles meant return to me. I then overlayed the collar beep with the same thing - 1 collar beep meant sit, 3 collar beeps meant return to me. So while training, blow the whistle and do the collar beeps simultaneously. Then transition to just the collar.
Always keep them on a leash or check cord so you can immediately correct any action, don't ask them to do anything you can't immediately enforce. For instance, I wouldn't ask a puppy to sit if I cannot immediately correct them if they disobey. I would have them on a leash walking at heel and pull up on the leash while saying sit, which forces their butt to the ground. They learn that obeying means the pressure of the leash is let go. When introducing the collar beeps, do the same thing - walk at heel on a leash and say sit/blow whistle 1 time, while hitting the beep one time. Then transition to just the beep.
When training "here/come" I do the same thing but on a check cord. I never say they command if they are not on a cord than I cannot easily correct them, or else they will learn that their is no consequence if they don't listen and you end up being that person who is always yelling "come" at their dog in the field. Use your command, then give a bit of a yank of the check cord to start reeling them in.
I now only use the whistle if he loses sight of me for a long time in a thick area - hunting wooded area, corn, cattails, etc. The whistle can let him know where I am at, whereas the beep only lets him know to return to me, but he might not actually know where I am at. It's allowed us to be a very silent team in the field with most of our communicating via the beep on the collar, and very rarely any talking or whistle.