On 2011-10-24 4:10 PM, BRYON PAUL n0ah VEAL wrote: > I have a good friend who has a 1/4 wave 80 foot vertical (63 feet) who > decided to put a 100 foot coil to bottom feed the antenna for 160M. Using a > tuner, (no UnUN) he is resonant at 1.830 but the signal is very broad banded > at 4 miles away. Originally, he started with a coil made of 50 feet of copper > and was resonant at 1.890Mhz. Any red flags with this design to warrant this > problem of hearing him 30KHz wide, (10 up, 20 down) ?? On the scope, the > signal looks very clean, and I only see it 3-5 Khz wide, as I would expect. > Hut he is transmitting CW on LSB using CW software. The coil is only around > 2 1/2 inches wide- I am thinking larger turns would be less of a coil- Any > suggestions appreciated- this is not an antenna I understand very well but > would like to get some input- The station is very clean for issues but is the > coil suspect- I think I would just gone with an Inv L....... hihi > Please feel free to respond to [email protected]. > > Paul N0AH > > Base loading coils for short verticals can have a very high RF voltage across them (and also the base insulator). If he's running high power, there's a chance there is some arcing going on.
Maybe he's inadvertently running "spark gap" instead of CW. 73, Terry N6RY _______________________________________________ UR RST IS ... ... ..9 QSB QSB - hw? BK
