Well, the nice-to-have mails just keep coming and this one came from Chip, K7JA who become well-known in HAM circles after appearing on the Jay Leno show with K6CTW where they went head to head with SMS text messaging to show CW was the fastest text messaging available! Chip, who is VP of Sales at Heil Sound in the USA had this to say about his new beam:
Just wanted to drop you a note to advise that I just put up a 6-element homebrew LFA yesterday, and it seems to be a real winner. Haven't worked anybody on it yet, owing to the terrible conditions recently, but the SWR is spot-on and the pattern is really excellent.
I built up a version of the 6.8-meter 6-element LFA. For the loop, I used right-angle pieces salvaged from the resonators of defunct KT-34XA tribanders. The tubing is 3/8" diameter, so it mates with 1/2" perfectly for the driven element.
The parasitics are mostly 1/2" copper tubing (0.625" O.D.) salvaged from an earlier beam project. Yes, they're heavy, but they are very rugged and good for the strong winds we get here in the winter. The reflector is made from 1/2" aluminum (oops. . .aluminium, sorry), and I did a little tweaking in EZNEC to compensate for the slightly different element diameters from the original design on your web page.
The element mounts are made of dry wood, painted with many coats, and then wrapped with electrical tape (as are the centers of the elements). The wood is slotted down its length, which gives a place into which the element can nestle before being held in place with cable ties (followed by another layer of tape to protect the cable ties from the sun). I realize the wood might affect the resonant frequency, but as I said the SWR is spot on and the pattern is absolutely what the model predicted. . .all lobes more than about 70 degrees off the nose are down at least 30 dB. I've attached a photo of the element mount, absent the tape, etc., for clarity. This photo is from the original project, a DIY-store OWA Yagi that I documented for Popular Communications magazine in 2007.
Thanks for a neat design and a most informative web site. If you want to use the photo, please feel free to do so. I have a higher-resolution version available, if you like.
Chip Margelli, K7JA
Garden Grove, California USA
The 6.8m long 6el 50MHz LFA as installed at K7JA
Why not build an LFA today, be apart of the LFA revolution!