Most of the ZEROFIVE ANTENNAS are non resonant vertical antenna that work well for DX, first of all being non resonant they don't bring in extraneous band noise, you get a lot better signal to noise radio in less than ideal radio conditions, (you can hear the other stations better) Thats better than trying to take noise away from the signal with a DSP unit that always adds something to the incoming signal, fact is a signal will always come over the noise in radio reception, an antenna tuner will have to be used for a decent signal output of the radio used. I have a ZEROFIVE 43' that I have been using for 3 years in two different configurations with good results on 10-160m. My first setup was the way ZEROFIVE recommends installing the 43 vertical using a full range tuner and using a UNUN and a coil on the 43' vertical antenna this worked well up to 200 watts at my location, but after 200 watts the efficiency dropped. the present setup uses a screwdriver antenna in series with the 43' stinger and 3500' of radiales that range from 18-60' under the antenna, the antenna system will take 1000+ watts with 1.1 SWR which works very well on 160, 80 and 40m with fair results on the upper bands.
By taking off 5 section of the vertical stinger and making the stinger 27' that made the antenna a flame thrower on 40m it still works 80 an 160m. I just ordered the 27' Zerofive ground plane antenna that works 10-40 with an antenna tuner, for the higher bands to take advantage of the higher Sun Spot count for some good DX..........KB6HRT