Santa very kindly left me with a new addition to the radio set up yesterday. A 5 element LFA antenna from InnovAntenna’s. I must admit I gave him a little steer in the right direction but even so it was delivered on time.
Its figures suggest its a good yagi for my QTH for use with the local net and SOTA / WOTA on FM and into the NI repeater GB3NI at a push.It’ll also be useful for any back packer work as well as club special event stations if needed. The website throws the usual information and as always it should be read in conjunction with your own experience of your site. Never less the numbers are:
Gain: 11.16dBi @ 145MHz
F/B: 19.59dB @ 145MHz
Peak Gain: 11.18dBi
Gain 10m above ground: 16.93dBi
Peak F/B: 20.32dB
Power Rating: 5kw
SWR: Below 1.4.1 from 144MHz to 146MHz
Boom Length: 1.789m
The antenna came in a large cardboard tube but with nothing else in it, no clues as to assembly, which is odd as you get pages of helpful advice from people like Sotabeams who sell cheap out and about antennas. It also states that the elements are solid 1/4 inch (6.35mm). Although mine were not and the use of high quality insulating blocks is let down by the choice of threaded inserts. Which in my case spun one the box section holes that were drilled and made the insulators sit slightly proud of the section and hence area point which over time will allow fretting. One of the elements isn’t quite as secure as it could be and when I looked inside the box to see the type of insert used I was met by quite a few bits of swarf. Nice!
Still, the new toy is up in the loft (until I can sort out the wobbling elements. Each block needs a deeper countersink in order to make sure the raised insert sits fully inside the insulator and not on the taper of the countersink, if you follow that. The spinning insert will be dealt with by a bit of Loctite 603 or other bearing retainer before the holes get too big.
Whilst I am cheesed off that the manufacturing 
quality is a bit below par for my liking I’m sure once I’ve fixed the issues it will be a very useful antenna. Here is is in the loft aiming at GB3NI and getting in (just) and you can just about see a bit of the non perpedicularity / wonkiness of the loose elements. Once the go ahead for an exterior installation has been approved by the in house planning department I’ll be fixing it outside to make the most of the beam. Until that occurs I’ll be manually rotating it by going up into the loft and moving it about, There’s plenty of room up there so there is no problem and means that it’ll give me the kick I need to board out the rest of the central part of the loft.
