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 n0ah@arrl.net.
>
> 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
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