This construction by PA0FBK is a realy portable antenna to mount directly on the radio antenna connector. I have buildt a couple of them and they perform surprisingly well for their size. See my videos and PAoFBK drawing on my Swedish page.
You can buildt this in several ways, but the PL259 connector is setting the diameter for the coilform. I used an old fishing poole. The telescopic whip is in my antenna 1,8 meter, from Buddipole, but you can use 1,6 meter as well, thats original size. (Wimo). On the drawing the whip is mounted with washers and glue, it is also possible to place some nuts here and a screw in the bottom of the whip. That makes it more portable and give a shorter packing volume.
To make the coils with another diameters of coilform and or copper wire you are getting different values. Do the coils from top one in a time and tune that coil with whip fully extended. Do the same thing with all the other coils and you have a tuned antenna working really good. It is a nice Sunday work. Yes, also WARK band can be with us in the play, just do the extra tuning with the whipe. Konect on 40 m coil and tune with whipe for 30 m and so on.
So how good is this antenna?? I have no siffers but it works out in EU and little more.
After the last antenna was finished i sat down on a bench outside clubhouse and connected the antenna to my IC703+ and 2 ground wires for 20 m.
So i started to listening, first on 80m, there was some stns from south of Sweden but weak signal and qsb, so i continued to 40 m. Here i found SM2CFZ who called cq. I got him, he was in Haparanda, northest of Sweden, at the end of Botnia bay. He gave me539 and i returned 589.
Now to 20 m, here i transmitt cq a several times and got a cach after some time, it was DJ5AA Al in Dresden who answered me. Here i got 419 and i returned 339. Al changed power and came back with 5 W and an W3DZZ he got 229, his signal was on the edge of the noise, it was his clean and nice signals who carried it all in the bottom of the qsb.
So, just go and make you an own Outbacker an have joy.