Been a long time.But with the recent improvements in conditions on 6 I have been able to do more testing.I'm pleased to report the co linear definitely works. During an opening I tested with several vk2 ,3 ,5 and 7 stations and the co linear works as well as my latest 4 el yagi.
Also worth noting on the construction .
I used 300 ohm ribbon for the feeder and the phase lines My tv ribbon ended up shorter than the 47 inch he posted
Using a grid dip meter mine came in at 45 inch.So a different VF. If you dont have a dip meter or analyzer you can terminate one end with a 400 ohm resister and do a swr sweep with low pwr,
You should get a reading of about 1.2 to 1 at resonate frequency.
Now this length is good for both the phase lines and the two lengths for the line trans former The author uses two parallel 1/4 wave lengths of ribbon for the line transformer.All good ,but he doesn't mention you have to separate the lengths with a spacer. DO NOT TAPE THEM TOGETHER.
To fine tune I left the last, 110 inch ,1/4 wave element a little long and folded the end back until i got band section I wanted. ( namely the ssb portion of all 3 bands ).A little juggling was required when I got 50.110 right the low swr on 2m was at 147.