| Topic |
Author |
Posted On |
| marine mobile antenna - power boat |
W2HDI |
on 3/5/16 |
| Ground to a porous phosphor bronze bonding/grounding plate mounted on the hull or transom below the water line. It has huge effective ground surface area because of its' porosity, and seawater makes the best possible counterpoise for a horizontal wire or vertical antenna, far superior to the rail. |
| baluns |
0001529375H80 |
on 3/5/16 |
| It depends on how you want to feed the antenna. If using Coax, you want a 1:1 balun with a current choke, or use a separate current choke between your transmitter and tuner. To feed it with ladder line, you would typically either connect it directly to the balanced output of an antenna tuner, or run a short length of coax out of the radio room into a 4:1 Balun connected to the ladder line to transform the 50-75ohm coax impedance to the 200-450 ohm impedance of the balanced line. The shorter the coax, the less lossy the overall system will be. Ladder line is far superior when it comes to loss over coax under high SWR's, like when using the antenna with a tuner on a band on which it is not resonant. |
| Ants |
talljames |
on 3/5/16 |
| If you can rig something up where the line passes through or dips into a tray of water, or the end connection is surrounded by water, it will stop them. Another option is "Tanglefoot" sold at nurseries or farm supply stores. It is extremely sticky, designed to trap insects. |
