suggestions for newby

Discussion in 'Amplitude Modulation' started by KK4RSV, Apr 25, 2019.

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  1. K4KYV

    K4KYV Subscriber QRZ Page

    Or else, get some #6 copperweld, and daisy-chain several small johnny-ball insulators at the middle to insulate the two legs at the feed point. That way, the messenger line is effectively contained inside the antenna wire. The retiree who was thinning his radio collection and gave me a roll, had used the same stuff to guy two 100' towers that had been up for 10 years at the time. You could probably safely use it for a tightrope act.
     
  2. W2VW

    W2VW Ham Member QRZ Page

    Ok ok so it probably won't do well with 45KW of 8VSB at 605 MHZ.
     
  3. N2DTS

    N2DTS Ham Member QRZ Page

    In my case, I have the 80/40 meter fan dipole made from 12 stranded insulated copper wire with 14 or 16 gauge below it for the 40 section, no balun, held up very tight by thick dacron rope (HRO sells it) with rg8x coming down 40 feet or more.
    Been up for about 10 years without trouble.

    The other fan dipole is an alpha delta LB antenna with a 20, 10 and 6 meter leg under it.
    The LB is made from 14 solid copper, as a full length 40 meter element, then a coil for 80, then a coil for 160.
    It does not work well on 160 or 80 but it does work, and makes a good RX antenna.
    I HAVE made contacts on 160 (Buzz up in Rhinebeck NY) at 25 watts (Icom 7300), but its too short to be any good.
    It also has no balun and its been up for 6 years or so.

    I am going to have all the trees trimmed and re do the antenna's and might just go with one fan dipole for 80, 40, 20 and 10.
    10 just because its so easy.

    We have had some BAD storms yet the antenna's never came down.
     
  4. K5UJ

    K5UJ Ham Member QRZ Page

    From W7WLL on the Tower Talk email list, this is reportedly what is used by fishing fleets and may be a good bet for a ham on the seashore. "I've never had one break under the most severe conditions. Do need to secure the ends because it is twisted. A little flame or dipped in resin. Available at ship chandlers and suppliers. Withstands salt, UV and rain."
    https://www.eversoncordage.com/tarred-seine-twine
    Around here I've used regular Dacron (not the hamfest knockoff) for years and never had a problem. When it's new, it stretches for a time but once that's over with and it has weathered, it's tough rope. But I don't subject it to real high tension.
    This material looks good. They were at Dayton but I've never tried their rope: https://www.mastrant.com/index.php?option=com_content&view=article&id=7&catid=2
     
  5. W2WDX

    W2WDX Subscriber QRZ Page

    I can attest to Mastrant. Much better than regular Dacron (which is also very good in most cases). Mastrant has a higher breaking point and less stretch than similar thickness Dacron. It's UV and chemical resistance also appears better, on paper at least. I know the break strength is better, having hung my full body weight on a 4mm Mastrant cord.
     
  6. K4KYV

    K4KYV Subscriber QRZ Page

    I use about a 300' run of Phyllistran between each of the ends of my doublet to the wooden poles where they terminate. Mine is the older type that uses the epoxy potting compound at each termination, which I trust more than the pre-form grips they now use, since a mechanical grip like pre-forms or cable clamps grip the jacket covering, not the synthetic fibre itself, whereas the epoxy potting material fuses with the actual fibres. I have heard stories of failures, where the rope fibres pulled through the outer jacket when U-bolt clamps were used.

    Phyllistran used to sell direct from the factory. It was expensive, but affordable. Then they switched to selling only through a middleman like Texas Towers and the price skyrocketed. For guyed towers, I'll stick with EHS cable broken up with strain insulators.
     
  7. KD6CXW

    KD6CXW Ham Member QRZ Page

    I was going try my new fan dipole with RG-59 or RG-6 with a steel suspension wire or some know as a messenger wire for the dipole and tie all three together. the messenger , shield and center conductor. the balun box acts as the center support with 1/4 inch rope holding that and I use braided masons twine to hold the dipole ends to the supports.
    Also use a few raps of rope on the feed line to take stress of the connection . The mason line is only good for 120 lbs. and would need changed in a couple years. if the antenna works then i'll change out the twine with something heaver .
    I'll try the balun like W2WDX maybe a 4 core and use rg 142 or 303 to wrap the cores. I hope it will handle a KW AM .
     
  8. K4KYV

    K4KYV Subscriber QRZ Page

    Build the fan dipole using #8 copperweld and strain insulators for the longest radiator, with lighter weight solid copper for the rest (even soft-drawn stuff from a big-box store would do), since it would have negligible tension.

    For my station, I prefer OWL with a balanced tuner in any case, but would not recommend any kind of fan dipole, multi-wire flat-top or cage dipole in an area prone to major ice storms. Not just the antenna itself, but the end supports are prone to failure with a heavy ice load. It could probably be made to stand up with a set of heavy-duty supports, including one at the midpoint for the antenna and feedline.
     
  9. KM1H

    KM1H Ham Member QRZ Page

    Ive used #12 solid Copperweld (the real stuff) with a heavy black poly jacket since the early 80's and no failures yet and even reused when I moved here in 89.
    Sold as rural telephone wire I bought 500' reels (easier to move than 1000') for wire antennas and Beverages.

    With a 135' dipole strung between the near tops of a pair of 70' pine trees and fed with RG-213, a pair of heavy duty springs kept it from going wild in wind storms; #14 stranded copper was hung as an inverted V for 40 and did well until the second tower and a KLM 40M4

    I came close to losing a 100' tower with a 4 el Christmas tree of homebrew W2PV 20-15-10 yagis due to heavy snow laden pine branches rubbing on the Phillystran. I used that as the tower was shunt fed on 160 but it was replaced with free CATV surplus 1/4" EHS plus Preforms; and a case of 504 Johnny Ball insulators was bought direct with my business discount and those are on all 4 towers here.

    The trees were also trimmed!

    I have absolutely no use for OWL and dont even own an antenna tuner as the various amps pi networks are easily modified to do that without the hassle of an external box. Since I dont live on one band or frequency it makes rapid QSY's very simple and fast.

    Carl
    Ham and CW since 1955, AM since 56 and SSB added in 57
     
  10. K5UJ

    K5UJ Ham Member QRZ Page

    What a heck of a good deal. We don't see anything like that nowadays.
     

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