I was given a Cushcraft 50-5s just for taking it down. Now, go to this
site http://6mt.com/6tech.htm and scroll down to "Cushcraft 5 ele mods
extended boob, optimized A50-5s.w5wbv.pdf. Basically, a whole new antenna
as the boom is extended to 17.5' (very easily I might add) and the ele
spacing/lengths have been computer optimized. This "new" antenna has almost
the same performance figures as the factory 6 ele.. There are a lot of 50-5
antennas out there and should be easy to pick up. Also, the mod is
inexpensive. GL and 73
Dave - KB4ET
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>Several years ago I bought a 6 el Cushcraft beam from Ron W4WA. I brought
>it home and got a stiff warning from VHF Contesting guru W3ZZ (ex K1ANV)
>that the older design Cushcraft left much to be desired.
>
>I pulled the 5 el and 6 el manual from the cushcraft page (for free). First
>off I noticed that the elements
>were now all one size center with smaller pices of aluminum telescoped to
>make the element ull size. This changes the parameters in a modeling
>program as to spacing and length.
>
>I did not have room in the space available (attached to my chimney) to use
>the full 20 foot 6 el version. So I opted for the 5 el on about 11 foot
>boom of the 605S
>manual. I made the lengths exactly the size per the manual and spaced them
>as per the manual. On NEC4WIN it looked good but the gain was only 6.9 dbi.
>I then made changes to the element lengths and found that adding to the
>reflector 2" and shorting the 3rd and 4th directors (the element spacing was
>fine) that I was looking at 8.4 Dbi. The only way to make further increases
>was to lengthen the boom to 14.5 feet which was not an option. I ran these
>by Joe W1JR and he agreed they looked good...he designed the 605 and 606S.
>
>I would not pay the price current price for the newer version but would copy
>the 605 or 606S design including the tubing sizes since you can download the
>manuals. This way you only use two sizes of aluminum but your still have to
>fashion the gamma match. For the less brave you can probably buy the gamma
>mechanism from Cushcraft.
>
>I tried the 5 el three times and working stations was much easier than with
>the 4 el Comet HB9CV beam
>(11 foot boom). Both antennas were on a military mast 6 feet above the
>chimney and about 35 feet above the ground. Using the FT-920 barefoot the
>guys on the 6 meter net said I was loud and I worked two in Europe on SSB
>that I could not make with the 4 el.
>
>The only cost was the original cost of the old beam and some work in doing
>the modeling and adjusting the element lengths.
>
>Don't have an antenna and want to get on? I found that my 2 el cushcraft 40
>worked Ok. I worked 23 countries (NA, SA) and many states (bunches of W6
>and W7). Other SECCers in Alabama used their 15 meter beam with good
>success.
>
>73 Dave K4JRB
>
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