Луис мне прислал тут письмо с описанием своей антенны.
90м вертикал.
Насколько я понял, конструкция похоже на ту, что испытавл недавно Андрей RN3AGC - удочка с балкона и два провода параллельно вниз.
Заземление- трубы холодной воды.
Только живет он повыше, потому и эффективность антенны получлсь в разы повеселее.
Пишет, что усилитель перенес на терасску крышы, я так понимаю чтобыне шумел вентиляторами и не мешал домашним спать и готов вещать чуть не круглосуточно. -)
Оригинал ео письма:
Привет Роман !
I have answered in the Russian group. Hope Google translator is not extremely bad on Russian
I'm using English->Russian translation, which should work better than Spanish->Russian
Hope to get the PA working in the top terrace soon. So I will be able to keep it running all night long
without fan noise at home. And then we will be able to get the good openings at sunrise in your QTH
I read that you don't understand how my antenna work. May be I can explain you, so you can translate
I live in a 26 floor building tower. The top terrace is flat (no roof with tiles) and about 80m to the ground
Then I have a 10m fiberglass pole. The pole supports a vertical wire and two sloppers to provide some capacity
about 150pF. The coils to resonate the antenna are also in the top terraza and the PA should be there. Actually
is feeded by a coax from QTH in the 16 floor
So fa so good. But the ground of the coax or PA is connected to a metal pipe which runs down the building to
the basement. This pipe is part of the fire extinguish system and is filled with presurized water and in the basement
connects with the main water distribution grid
So this is a 80m pipe which is not just ground but part of the antenna. The high voltaje runs from the coil to the 10m
fiberglass pole and sloppers. But from PA ground to the basement only RF current runs trought that pipe
The result is that the whole pipe is part of the antenna and radiates. So the effective size of the antenna is 80+10m
The performance is very very good. I have not being able to calculate the real radiation resistance, but should be high
And with 3A RF this antenna should be radiating a few watts. That's why my signal is strong
Another important thing is the radiation angle, which should be low, as the building is hight and isolated from others
and also the nearby mediterranean sea can help for a good takeoff to Reunion island, for example
73 de Luis
EA5DOM
А это результат его работы:
http://136.su/index.php/topic,18.msg24947.html#msg24947http://136.su/index.php/topic,18.msg24937.html#msg24937Усилитель мощностью 1300Вт
