Here it goes. And I'm really sorry for my drawing abilities.http://fotos.subefotos.com/71807bedc27c6a96b2b9887fb5e3a1e8o.jpg
4 floor house with lot of antennas on the roof. Only one is shown.
It is a 25 years old CB antenna from Tagra. It is undestructible so I'm not really interested in changing it for a (more capable?) AV-620 or the like. About 6 meters tall. DC grounded (or so I hope) with a coil to a 5 meters tall mast with 3 elevated small radials.
It performs awesome on 10,12,15. Great on 17. Passable on 20. And surprisingly well on 30 & 40.
DXCC on 10, 15, 20 in 1 year. And worked +100 entities on 40 17 and 12.
Coax lenght is 30 meters to ground level, where the shack and single gound point is. And I couple it with a MFJ-993. SWR is always under 3,5:1 (or so it says) in all the bands, so I think I can save the money on an external tuner.
There are about 20 ferrites (TDK) on antenna feeding point. Coax leaves the antenna horizontal form some 4 meters, then slopes down some 10 meters more. And I've installed a 16 turns FT-240-52 ferrite core where the radials end.
- Is there any reason to lay down all those radials (blue on the pic) at the roof, if I connect them to the base of the mast instead of base of the antenna?.
- What about the chokes? Am I losing anything installing them? They definitely kill RFI and improve RX noise. But don't know if I've overdone it.
- Is the perpendicular exit of the coax justified?. Putting it the usual way (parallel to the mast) would make it for a cleaner view.
Don't want to overdo if there is no reason. And I really don't understand what kind of antenna is this. I guess it is acting as a OCF dipole. But don't know what the extended radials are doing, or if they are doing anything.
Thanks for any comment.