There is always problems with frequencies that are multiples of the one you yourself use, so a 72MHz radio might have trouble with 144 (amateur band, I think) and 36 MHz - whatever that is, to mention a few. So while they will not broadcast on 'our' frequencies the equipment can well spill some of the radiation on 72 MHz ... Otherwise RC equipment would never be affected by cellular phones (high above our frequencies, garage door openers, pagers, et cetera)! So keeping a safety distance to equipment emitting many kilowatts is prudent if you are an RC modeler! I would, anyway! Tord, Sweden -- If reply difficulties - use [EMAIL PROTECTED] Tord S. Eriksson, Ovralidsg.25:5, S-422 47 Hisings Backa, Sweden RCSE-List facilities provided by Model Airplane News. Send "subscribe" and "unsubscribe" requests to [EMAIL PROTECTED]