7 Element 60' boom Yagi This is my new 7 El 60' boom Yagi. Its a beast at 80kg. The boom is constructed from 2 1/2 yacht masts.
The support rig is 43mm scaf poles welded together. Construction time has been around three months on and off.
Here it is under construction in the yard.
Its up supported on ropes until i'm happy with the tune then its going up on top of that tree that its pulleyed to.
That will get it to 70' then 40' of scaff poles welded for the remaining 30'. Total of 100' in final location.
Specs are not quite as EZNEC promised but not too far out.
Forward gain should be 13.2dbd and tests at 12.5dbd
F/B ratio should be 68db and tested at 63db at 27555 (38db within 200khz)
Bandwidth design was 850khz and is only 725khz for 1.5:1vswr
Pwr handling (gama temp limited) 1kw cont 2kw pep This was the worst surprise!! it gets mighty hot at 2kw! (90deg C in 45 sec)
wind area loading 1.6 sqm
Needs a 1000dx rotator to move the monster
Cost of antenna build £ 70 rotator £400 westflex £88
Once final on air tuning is complete i'll get it up on the rotator in about a week hopefully and weather permitting.
26FB193 John
Re: 7 Element 60' boom Yagi i take it that the green bags are full of red bull ,to help hoist the beast.
please dont point around 35 degs north east as i like my new radios?
catch ya soon as iam back on the radio again
Re: 7 Element 60' boom Yagi LOL The bags are full of crank up military tower bits mate you dont think i'd do all those years in the army without obtaining a portable 12m mast do you tehe. The plan was to set this kit up at Siomon's QT (204) for the open FB day, r u coming along? j193