Now we have a new version of multiband antenna:
The 2 band antenna for 20m and 30m.
Below you see it, installed as mobile antenna :



The tube has a length of 170 cm (including mounting space), and
measuring of the SWR has given the following values:
 
SWR when antenna is set for 30 m:

SWR      Frequency
2.0         10.010
1.8         10.028
1.6         10.044
1.4         10.060
1.2         10.080
1.1         10.095
1.0         10.106
1.0         10.145
1.1         10.155
1.2         10.168
1.4         10.190
1.6         10.210
1.8         10.228
2.0         10.255

SWR when antenna is set for 20 m:

SWR      Frequency
2.5         14.000
2.0         14.030
1.5         14.076
1.3         14.105
1.2         14.118
1.1         14.124
1.0         14.140
1.0         14.170
1.1         14.183
1.2         14.196
1.3         14.215
1.5         14.240
2.0         14.295
2.5         14.350

Values measured with MFJ-269 and 1.5m coax between feedpoint and instrument,
measured on May 1st, 2006.

The setting of "SWR 1.0" can be made on any frequency in the band.
By using the Remote Frequency Adjustement (RFA), the SWR 1.0 is changed from
14.000 to 14.300 within 3 seconds. The RFA is a feature included in detail in the
construction guide.

Comparisons with other antenna types will follow.

This antenna is also included in the construction guide.

And here a picture of the RFA control box: