Ken - From what I gather, your radios are not repeater capable. In other words, in order to trigger a repeater, the radios transmit 5 Mhz higher than the receiver frequency and usually with a selectable access code that the repeater needs to turn on. As an example, if a repeater is operating on the frequency pair of 462.550 out / 467.550 in with an access tone (CTCSS) of 71.9, and your bubblepack radios are on "channel 15" ( 462.550 both T & R ) with or without any CTCSS, you will not activate the repeater and if someone else does use the repeater, your radios will not interfere with that operation because of the power differences between the repeater output and yours. Just make certain that if you do use "channels 15 to 22" in your radios that you ID with your callsign after each communications string and anyone hearing you will know that you are licensed. If you ever upgrade to repeater capable radios, then before you do access someones repeater, get permission first.