[Antennas] fill the space?

2002年5月09日 13:23:22 -0700

At 12:50 PM 5/9/2002 -0400, you wrote:
>Hi. New residence has 200 ft of clear space with the house in the middle.
>Which size dipole do you think would be best for low bands?
>(I will put a small tribander beam up later.)
>>Shall i fill the space with 200 ft of flat top, up 35 ft, fed with ladder
>line?
>Is it better to cut for 80m ? I think i could tune 160m with
>200 ft and ladder line of 50 ft. right?

If you are wanting to operate on 160-meters then the 200 foot length dipole 
would be a better choice. Modeling your set up using NEC a 200 foot dipole 
on 160-meters (1.9 MHz.) would have the feed point impedance of about R23 
-J387. Using 50 feet of ladder line your tuner would see about R13 -J40 
which should be within the its range.
A dipole cut for the middle of the 80-meter band when used on 160-meters 
(1.9 Mhz) would have a feed point impedance of about R9 -J1130. Again using 
50 feet of ladder line would present an impedance of R2.3 -J250 to the 
tuner. I doubt the tuner would handle this and, if it did, the losses would 
be rather high.
In both cases you will be running a cloud warmer system. However, the 
longer antenna would give better efficiency.
73
Danny, K6MHE