The icom runs a max of about 65 watts but almost always less, more like 5 or 10. The antenna I hope to set up is a mobile 5/8 waxe over a ground-plane. My purpose is for skywarn activations, as an NCO it would help to be active one two frequencies nearly simultainously. Any further help is appriceated.
--- In Repeater-Builder@yahoogroups.com, "Eric Lemmon" <wb6...@...> wrote: > > Jeremy, > > You did not provide enough information to give you a good answer. How far > apart are the frequencies involved? How powerful is the other radio? > > What I can tell you right away is that vertical separation is far, far, more > effective than horizontal separation. If both radios are going to be > frequency-agile, that is, there may not always be a fixed separation in > frequency, then the simple answer is: Separate the two antennas vertically > as much as you can, one over the other, and hope for the best. Use > double-shielded cable for feedlines on both antennas. > > Damage to the receivers is not likely, since most good radios have diode > protection on the front ends. After all, look at almost any "mobile command > post" vehicle, and you'll probably see a dozen antennas on the roof- usually > no more than a foot or so apart. Although major desense is almost > guaranteed when any one of the radios transmits, judicious use of > preselectors (such as those made by DCI) can minimize it. > > -----Original Message----- > From: Repeater-Builder@yahoogroups.com > [mailto:repeater-buil...@yahoogroups.com] On Behalf Of Jeremy (KB1REQ) > Sent: Monday, October 26, 2009 6:24 PM > To: Repeater-Builder@yahoogroups.com > Subject: [Repeater-Builder] Antenna spacing > > > > This post does not necessarily relate to repeaters, but some of the same > calculations can be applied. I am interested in installing another two meter > radio in my shack and was wondering what kind of spacing is needed as to not > over load either of the radio's receivers. I currently have an icom set up > on a j-pole, and I have a 45 watt GM300 that I want to add. What would be > the best placement of antennas to reduce desense. or otherwise damage the > receivers? >
