Antenna tuner and G5RV

Discussion in 'General Technical Questions and Answers' started by KD9MLU, Aug 15, 2019.

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  1. KD9MLU

    KD9MLU Ham Member QRZ Page

    As a beginner ham, with a general license, I am thinking of using a G5RV antenna for my (used) HF radio. What is an entry level (inexpensive) antenna tuner to use with the G5RV?
  2. K7TRF

    K7TRF Premium Subscriber QRZ Page

    One of the MFJ tuners like a 941E or 948 or similar would get the job done if you're running a 100 watt rig. Remember to de-rate the power you can apply to tuners depending on what kind of load you're trying to match. IOW, these '300 watt' tuners are pretty good to 100 watts for a half decent antenna load impedance but for hard to match antenna systems you might start getting arcing across the tuning capacitors at lower power and they'll only really support 300 watts when the load is already a pretty good match.

    If you'll run more than 100 watts or want a tuner that will match into good, mediocre or really bad loads at full power then think about a tuner that's rated for higher power. Something like a vintage Heathkit SA-2060A fits that bill as do a lot of newer tuners sold as 1kW or higher power tuners like those from Ameritron, Palstar and others.

    You might also want to compare the G5RV to variations on that theme like the ZS6BKW that tends to provide a bit better match on more of the HF ham bands but is basically the same antenna concept with some changes to the element lengths and length of the balanced feed line matching section.

    Remember that in either of these designs the section of balanced feed line used for impedance matching should run perpendicular to the antenna for its full length (e.g. ~31' for the G5RV) in most installations that means it can hang straight down or at an angle perpendicular to the antenna for that distance. That pretty much means you'll want to be able to get this antenna high enough so that the matching line doesn't touch the ground or have to run up against things like trees, your roof top or worse yet metal surfaces.
    N7BDY likes this.
  3. W1VT

    W1VT Ham Member QRZ Page

    If the SWR drifts that is a sign you have a ferrite balun or similar that is overheating and need to fix that. Or reduce power until you do.
  4. K8JD

    K8JD Ham Member QRZ Page

    Why isn't this in the ANTENNA FORUM ???
  5. KD9MLU

    KD9MLU Ham Member QRZ Page

    My question was about a tuner, not specifically about an antenna. Seemed like a technical issue to me. Shoot, give me a break... I'm new here and it's responses like yours that discourage a new guy - me - from posting anything. Why not just suggest this topic may fit better in the XXX forum instead of the sarcastic response you gave?
    WD6USA, KS4W, KK4NSF and 2 others like this.
  6. KD9MLU

    KD9MLU Ham Member QRZ Page

    ...and to K7TRF thank you for the information. I will check out the referenced antenna and tuners.
    KK4NSF likes this.
  7. W5DXP

    W5DXP Ham Member QRZ Page

    I have a ZS6BKW that works without a tuner on 40m, 20m, 17m, and 12m and with a tuner on 80m and 10m. I much prefer the ZS6BKW to a G5RV.
    W6MK likes this.
  8. K5DH

    K5DH Ham Member QRZ Page

    I'll second the recommendation for buying a used MFJ tuner. The 941 series work fine, but I'd opt for the 949E with its larger meter. I see them available frequently for $75 or so. You might also look at the 969, which has a roller inductor. The coil can be a bit hard to turn, but the tuner works quite well and they sell used for $125 to $150, not a bad deal. MFJ stuff has a reputation for being junk, but their tuners work quite well. Just be sure to check for loose hardware and poor solder joints. Those are their main quality problems. If everything's "tight 'n right", an MFJ tuner will last a lifetime.

    I'll also second the recommendation for buying a bigger tuner if you plan to purchase an amplifier. The Heath SA-2060A is a real bruiser (I used one for years). The MFJ 989 series will do fine also (had a 989C for a while). Lots of choices out there. It mainly comes down to your budget.
    W6MK likes this.
  9. KF4ZGZ

    KF4ZGZ Ham Member QRZ Page

    If your radio has a built in swr meter you can get a tuner that doesn't have one.
    IMHO, the MFJ-901 and it's variants are the best tuners MFJ ever built.
    Small, light, and they will tune practically anything you can hook them up to.

    I doubt you will find one as cheap as I did .... mine was 20 bucks years ago on ebay ..... but ya never know!
  10. W5LZ

    W5LZ Ham Member QRZ Page

    If possible, I'd much rather make my own than buy an antenna. There are NO antennas that haven't started out as a typical "garage" build kind'a thingy. If there's a particular antenna that would suit your specific use, then I would say to use that sort of antenna. is NO one specific antenna that will do everything. So, count on having more than one antenna. If that's not possible, the count on at least one gopod band use, and a sort of so-so ability on other bands. Sorry, you can't get around that. Actually, being less than 'perfect' on a lot of bands isn't all that bad...
    WD6USA likes this.

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