These are very popular antennas as they cover many bands and are fed from the end making them ideal for /P operation.
As the end of the wire is often a very high impedance a transformer is needed to reduce this to closer to 50 ohms.
I see there is a new video about an end fed long wire on the DX Explorer video channel.
Last year, this developed a fault.
I strung an end-fed wire using the Par transformer out of the shack window. The VSWR looked low, so I assume this Par transformer is fine. At some point I shall re-erect this tri-band antenna, but with new coax. Either there was moisture in the coax or the plug had failed.
In the past I have been spotted all over the planet with this antenna and 500mW WSPR on 10m. It is good for 35W, although my absolute maximum is 10W and often much lower. With WSPR and FT8 it is far lower.
