With the demise of the EFHW, I decided to revert back to an EFRW. I don't know why they call it a random wire because there are set lengths that you use to get the best results. I tend to just refer to it as a long wire. This would only need a wire length of 58 feet, which makes for an easy fit in the garden. No need to divert around trees and the like. It is a straight run from the apex of the roof to the support pole at the bottom of the garden. However, the transformer would have to be reworked from a 49:1 to a 9:1 ratio (above diagram). That was easy enough to achieve. The secondary windings were reduced from 14 to 6, sticking with the 2 turns on the primary. I removed the capacitor also. Two type 240-43 ferrite rings were used as before. This is no longer a resonant antenna on any band, unlike the EFHW which is resonant due to utilisation of the harmonics. Running a check on the VNA confirmed that this would be promising with regard to SWR readings on all bands from 1.8MHz up to 28MHz. A higher SWR was observed on the 7MHz band and the 24MHz band of around 2.5:1 but nothing the ATU in the rig couldn't handle. I found that a 1m long counterpoise wire was sufficient to reduce the SWR readings even further and hopefully help with common mode current flow. A common mode choke was also employed on the coax close to the feed point.
Conclusions:
The antenna performs as expected. Several good DX contacts were achieved - even on 10W. I rarely run above 30W anyway because I use mostly digital modes. I find this to be sufficient for contacts all over the world. These contacts include USA, Canada, Brazil, Suriname, Ukraine, China and most of the European countries. I have noticed though that the noise level may be higher. Not sure why this is. It doesn't appear to be on all frequencies. Could just be the normal noise level on a particular day. Conditions haven't been the best recently anyway. Overall, I feel more confident with this antenna than the 'fickle' EFHW.
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