It doesnt really work that way, unfortunately. The first few directors add the most additional gain, then with additional directors the additional gain tapers off to the point of marginal utility.So theoretically, seven additional directors buys you .4 x 7, or 2.8dB of gain; just about double the signal power.
Yes , I recommend doing a few things to increase durability and longetivity . I just had to take the antenna down to replace the rotor that wasn`t giving me a full rotation ( quite old ). BTW the Source is clearing them out for $50. Great deal !!! GeoStar commented on how his directors are coming loose . I questioned myself on that when i was assembling the XG , one of the elements fell off due to it was bent where it snaps into the plastic holder from the factory . Thanks to 300 ohms idea of using adhesive for the directors , i used pcv adhesive by applying it to the topside of the director letting it run down between the director and plastic holder filling the gap , should hold alot better . I also didn`t like how the rubber seals on each side of the balun sealed so i used black silicone to make sure that was sealed up good .goforit said:So for those with new 91XGs, is it recommended to seal all fasteners/joints with a lock-tite substance- to increase durability/longevity?
I have no idea where you got the .4 figure from.that's 5 additional directors, and at .4 * 5 that ought to be just 2.0 dB.
But if you have that book handy, look in Chapter 11 - HF Yagi Arrays, page 11-10, figure 10. It will show you the marginal gain drop off curve of more directors and longer boom length. For example, you need to add 9 directors and 4 1/2 wavelengths of boom to go from 18 dbi to 20 dbi with a theoretical optimal yagi.- ARRL Antenna Book, 21st Ed.
I applied Plumbers Goop/Loctite Plumbing and Marine Adhesive on the loose/cracked reflectors on my Antennacraft corner reflector about a year ago. (It dries semi-hard unlike silicone sealant, and is also non conductive ) The exposed glue still looks good, with no signs of UV damage so far.Thanks to 300 ohms idea of using adhesive for the directors , i used pcv adhesive by applying it to the topside of the director letting it run down between the director and plastic holder filling the gap , should hold alot better
Yeah, around to 180, then to 90 then to 270 and then to 169 and still going, heh.I think most of us have had some 180° turns in our thinking