jfhtm350
Member
Ok folks. This might be a deep pile of stuff im stepping in here, but i have an old magnetic mount cb antenna that i want to use for my mobile scanner. It has a coil in the middle of it. Ive tried to read up on antennas but I dont understand exactly what they are talking about.
My way of thinking is that I want it to be tuned to 460.475 Mhz, since that is about middle of the road between 800Mhz channels and low band and also that is the sheriffs dept dispatch here.
From what I understand, is that 5/8 is as long as you want to go as it looses gain after that. Is that correct? Originally i was planning a full wave until I read that.
According to this page ( Amateur Vertical Antenna Calculator by dxzone.com ), 460.475 at 5/8 wave is 1' 3 1/4". Now is this measured from the bottom of the base to the top of the antenna with a measuring tape or is the length of wire in the coil factored in with the measurement? There could be 2 to 3 feet of wire wound up in that coil and the coil is only about 3 inches long.
My way of thinking is that I want it to be tuned to 460.475 Mhz, since that is about middle of the road between 800Mhz channels and low band and also that is the sheriffs dept dispatch here.
From what I understand, is that 5/8 is as long as you want to go as it looses gain after that. Is that correct? Originally i was planning a full wave until I read that.
According to this page ( Amateur Vertical Antenna Calculator by dxzone.com ), 460.475 at 5/8 wave is 1' 3 1/4". Now is this measured from the bottom of the base to the top of the antenna with a measuring tape or is the length of wire in the coil factored in with the measurement? There could be 2 to 3 feet of wire wound up in that coil and the coil is only about 3 inches long.