Roomcap 2nd
Generation: more
27th April 2013
/ upd 2nd May 2014
More about the new Antenna Generation
Instead of the thick tube (5cm dia)
a lattice is used as radiator.
The radiator measures 1m x 1m (light lattice with small
wind resistance), abt. 50 cm above the roof of the car.
This radiator serves for the 4 bands: 20-30-40-80 m, as seen
here: (New =
10-12-15-17m = all 8 Bands
!)

Comparing to the traditional
Roomcap, a further significant increase of the field
strength in the far field,
and a significant enlargement of the bandwidth is obtained.
Here follows the SWR and impedance diagram of the new
antenna on 40m: (measured on the the antenna seen above)
Red curve = SWR, green curve = impedance Z
(compare the SWR bandwidth with the version of the thick
tube here: /ant5jan11e.htm )
See the low SWR in the 40m band, and furthermore, the RFA
(Remote Frequenca Adjustment)
allows to set the SWR in seconds on any
frequency to the minimum value SWR 1.02 : 1.
An antenna tuner is not required for the Roomcap! You can
forget it.
--- --- --- --- ---
AND:
This antenna serves equally well as home antenna on the roof
of your house.
What a difference in size to a half wave dipole, or quarter
wave GP!