I have offered to help a friend of mine put up a decent antenna on 40/80/160.
He's a DXer close to Honor Roll operating only 10/15/20. As a starter
antenna, I suggested parallel inverted L's, and I want to run this by the
antenna gurus before I proceed further.
He has a couple of 50' pine trees about 50' apart, near his house.
With my slingshot and some fishing line and some dacron rope, we can get the
dacron rope from the top of one tree to the top of the other with a 40M
vertical, an 80M inverted L and a 160M inverted L tied off about 5'-10" apart
at the 50' level. The extra 15 feet of the 80M inverted L would follow the
dacron rope towards one of the trees. The extra 80' of the 160M inverted L
would be attached to a third tree about 90' away and perpendicular to the
dacron rope between the two trees. All three antennas would be conected in
common at ground level where the shield of the coax would go to some ground
rods and a radial system. I'm well aware of the importance of the radial
system.
Years ago, I used parallel dipoles which worked OK. I've never heard of
parallel verticals, but see no reason why they shouldn't work? Due to the
proximity of the vertical elements (together at the bottom and 5-10 feet
apart at the top) do I need to change any of the 1/4 wl dimensions? Does the
spacing at the 50' level of 5'- 10' or so make any difference?
On 160M amps. I have used my older Ten Tec Titan on 160M for several years,
never running over 1500 watts out and usually at the KW level. A year ago,
L3 (I think) started heating up badly even at the KW level, and the output
becomes unstable on 160M after a few minutes of operating. The amp works
perfectly on all the other bands at 1500 watts out. I haven't been very
active on 160M this year because of the problem. Has anyone else experienced
this with the Titan? Ten Tec would like me to ship the amp back to them,
but have offered no real solution when I've talked with them. If I were to
buy a new or used amp sometime, which ones will run all weekend with 1500
watts out on 160M without problems?
Doug W0AH Woodland Park CO
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