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  1. KB3SKU

    KB3SKU Ham Member QRZ Page

    it will be easier to read all i have to read is a bar with spikes coming from it. Hard to tell exactly what im seeing :(
     
  2. AB8ZL

    AB8ZL Ham Member QRZ Page

    You might want to verify that the built in SWR meter works from the VHF/UHF jack in the first place. I’m not sure about the 897D, but on many DC to daylight rigs the SWR meter only functions from the HF/6 meter antenna jack. My IC-7000 is that way and has only one small note in the manual (easily overlooked) mentioning that.
     
  3. AI3V

    AI3V Ham Member QRZ Page

    Whatever,:rolleyes:

    My 2M rig works- have 32 states confirmed, direct.
    on 70cm I only have 26 states.

    You have all the info, and gear you need to tune your ringo for local repeater work.

    From your OP, you don't understand the difference between receiver and transmitter frequency.

    $pending more money on ANOTHER meter will not help.

    Good luck OM, AI3V QRT

    Rege
     
  4. W0IS

    W0IS Ham Member QRZ Page


    That's what I was thinking, too. But the SWR does seem to increase as frequency increases.

    On 146.10 it's pretty good. On 147.645, it's pretty high, but doesn't set off the High SWR warning, and on 147.825, the SWR warning starts flashing.

    The original poster doesn't need to spend $100 for an antenna analyzer. The antenna is too long, and needs to be shortened slightly. That's the only useful information the antenna analyzer will give him, so if he's so inclined, he can send me the $100 :D

    There's undoubtedly some screw that can be loosened, which will loosen up one portion of the antenna, so that it can slide in and out. Find that screw, and slide in that section of the antenna.

    At first, decrease the length by only a small amount (maybe a quarter inch). I bet there will be some improvement. Keep going until the SWR is acceptable on 147.225/.825. (Three "bars" on your Yaesu display will be perfectly acceptable.) Then, double check that it's still OK on 146.70/.10. That one might have gone down a little bit, but don't be concerned if it went up slightly.

    You can continue this process as much as desired. But at some point, it's best to declare that it's "good enough" and call it a day.
     
  5. K3DAV

    K3DAV Ham Member QRZ Page

    I was going to mention it if no one else had, but you beat me too it.

    The 897, 857, FT 100, Icom 706MKIIG and IC-7000, all do not have a functioning SWR meter for frequencies above 60 MHZ. The SWR meter is connected to the HF/6M side of the radio only. On 2M, the first bar may light up on the SWR meter just from stray RF inside the radio hitting the SWR sensor.

    Read those manuals guys.
     
  6. KB3SKU

    KB3SKU Ham Member QRZ Page

    Will this work for 2m/440?;

    http://www.universal-radio.com/catalog/meters/1198.html

    Just want to make sure before i buy it.
     
  7. K7JEM

    K7JEM Ham Member QRZ Page

    Mine seems to work on my 857 on 2M and 440.
     
  8. K3DAV

    K3DAV Ham Member QRZ Page

    That meter is made for your model radio so I can only imagine that it works where ever your internal meter works. If your internal SWR meter works on 2m/440, then so should the big external meter. If it doesn't then the big one won't either. K7JEM says his 857 reads SWR on 2M. It was my understanding that the mobiles that cover HF through UHF, did not have an SWR meter function above 60MHz. That is the crossover point from one antenna jack to the other, and the SWR meter was only connected to the HF/6M coax jack on the rear. My 746PRO reads SWR on HF/6m and 2 meters, so maybe they fixed that little problem.
     
  9. KC8KZY

    KC8KZY Ham Member QRZ Page

    Tell you what. If you really must buy an external meter, I have one here that WILL work for you. It's a 2m/70cm in-line meter, reads power/swr, and has the SWR/PWR correction curve chart on the back. As a bonus, it will work on ANY 2m or 70cm radio. $40 shipped to your door. Just remember, you have been given some GREAT advice here. Check your installation, check your coax terminations. Check the latter very closely, especially if you soldered/crimped the connectors yourself. If you bought pre-made assemblies, try having someone wiggle the connectors as you transmit. May be a long shot, but I've seen it happen.
     
  10. KM3F

    KM3F Ham Member QRZ Page

    Hello Jim,
    Be carefull about just taking in, looking at numbers and indications unless you understand what they mean.
    Because it won't advance your understanding by expecting a new additional meter to take the place of understanding what they are telling you.
    Please begin to look at it this way in sections, then put the sections togather for the whole picture.
    The antenna must match the transmission line as the first action.
    Do this by changing the length of an antenna element. On 2m it's quite sensitive to fractions of an inch and easy to over look expecting a half inch to work when it may be 'way' to much.
    To see this on the radio, turn the power down to about 5 watts and look at the radio's SWR function meter display.
    Key up and read. If it say for example 3 on the scale 'near the desired operation frequency' then move up or down 1 megahertz and measure again to see what the difference becomes.
    Doing this will tell you if the antenna element is to long or to short and to move it's length in a direction that results in a better SWR match at the antenna.
    If the radio does not have the function that will work on 2m, then you will need an external meter and it does not have to be a very expensive one.
    Matching down does not require a highly accurate meter for the following reason.
    When the match is near 1 to 1, the needle dosn't move much.
    With that being the case, when you adjust down to near flat, the meter is not reading very much reflected power such that meter accuracy at that point means nothing when the reading is no or little movement as there is no accuracy when reading a zero rest. Often this can be done with a meter that is ok for 10 or 11 meters use, saving you from spending extra money, at this point. Put another way, we don't need accuracy at SWR 2 or 3 to 1 because that is not what we are aiming at for an absolute accuracy reading.
    Lastly, deciding which way to go on antenna element length is determined by what happens to the SWR reading when you check a frequency above and below your starting point.
    For example, if the reading goes down when a higher frequency is checked, is usually means the antenna element is tending to be too short at the lower checking point and 'vice versa'.
    Using this method, you can dial the length in for best match in the middle of the band or the part of the band you most use. If you decide you need to cut some of to attsain match, be sure to double check the test readings before cutting.
    Don't do the testing on repeater frequencies and cause possible interference to their users.
    Good luck, catch you on 2m FM or SSB.
     
    Last edited: Jun 1, 2009
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