Lightning Bolt Quad installation By W7IS

Friday, October 14, 2005 Here are several pictures of the reflector and director before the aluminum welding wire is added.   I first spray painted the bare spreaders with a green enamle so that the speaders would blend in with the green evergreen trees in this area.  That also helped seal the sharp edges of the fiberglass spreaders. As without the paint it's necessary to use gloves to prevent injury.   The proper installation of the aluminum welding wire is another matter.   I spent a great deal of time testing the wire to find its weaknesses.   I ended up bending the wire over a 1/4" saw file with my fingers.  That gave the proper sized loop to attach to the stainless screws.   You need to be very careful to use only the very minimum of pressure on the nuts.   If you tighten the nuts  till there is no more resistance felt, it will have damaged the aluminum wire to where it will be very easy to break.  I used a jam nut over each nut to keep it from loosening up.  In order to keep tension on the wire while it was being threaded into the spreaders,  I attached a heavy pair of vice grips to the end of the wire and pulled the vice grips along the ground towards the element.   That prevented the wire from coming loose and coiling up.   The aluminum welding wire is very unforgiving and you have only one chance to get it right.   So take your time and be careful.  I used a 100ft fiberglass measuring tape and cut them to the exact length specified.   You should be able to substitute solid core 14 gauge copper clad steel wire without changing the tuning.   It will add a few lbs of weight to the ant and increase the cost by quite a bit.  I decided to live with the aluminum welding wire and take great care during installation.   The second picture shows the spreader with the unique wire holders attached.   After you thread the wire through the holders, you will need to establish the correct amont of tension for each wire by moving the wire holders in and out on the spreader.  You can set the spider on a 3 ft high support while making the tension adjustments.   That way you can see the amount of offset that the spreaders have.     When I got the quad in the air, I had the correct amount of offset on the reflector but not as much offset on the driven element.   Although it looked correct on the ground.  It might have had something to do with the heavy 2kw coax I used on the driven element --- which could have pulled the matching transformer back towards the center of the boom?  You just have to be careful to not put too much tension on the wires as then they can break under wind loads.  So set the tension so that its not too tight but still keeps the wires in proper position and it will probably be pretty close to being the correct offset.   The performance on 20m for gain and front to back ratio was excellent even though I might not have 10ft spacing on 20M. 

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