Needing to turn off Yaesu FT 450D in order to Tune.

Discussion in 'Antennas, Feedlines, Towers & Rotors' started by N3SE, Feb 27, 2021.

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  1. N3SE

    N3SE Ham Member QRZ Page

    Okay I have a G5RV antenna I am tuning 80 meters with an MFJ 969 Delux manual tuner since the Yaesu ft 450 d internal tuner wont touch the SWR . Periodically I need to turn off the radio in order for the tuner to tune. I get no forward power or reflected power on the meter. I set the inductance as well as the Antenna and the transmitter dial to the recorded values I have always used and the needles don't move. Once I cycle the radio off and on twice it works and I get a 1-1 match. Any ideas what could cause this?
     
  2. W9WQA

    W9WQA Ham Member QRZ Page

    ??..something missing ??
     
  3. N3SE

    N3SE Ham Member QRZ Page

    What is missing my friend The antenna is at 35 feet with ladderline to 75' of coax running 100 watts
     
  4. W9WQA

    W9WQA Ham Member QRZ Page

    ?. sounds like you are tuning with
    radio off?, no meter activity , no signal.
    we are more confused than you...

    is the radio putting out a signal when on?
    if yes then your tuner meters are??
     
  5. WG7X

    WG7X Platinum Subscriber Platinum Subscriber QRZ Page

    What mode are you using to tune with the manual tuner?

    It's normally done with a constant carrier mode like AM, FM CW or RTTY.

    Next question: are you using full power to do the initial tuning?

    Usually it is better to start low and then ramp up once you're in the ballpark.

    Here at radio WG7X I use at one time or another a Nye-Viking MB V A, A Palstar AT4K, or my one auto tuner, an LDG AT200. The metering is done thru an external watt/ SWR meter as well as using the meters on the various tuners.

    Next question?
     
  6. N3SE

    N3SE Ham Member QRZ Page


    Yes mode would help CW when tuning I do at 100 watts and to Question above yours yes both the radio and the Tuner are on at the time. And this only occurs on the 80/75 Meter band
     
  7. W9WQA

    W9WQA Ham Member QRZ Page

    im out...
     
  8. WB5YUZ

    WB5YUZ Ham Member QRZ Page

    You are putting the built-in tuner in "bypass" when tuning the manual one, yes?

    I'm sorry to be the bearer, but if you have been tuning the manual tuner at 100 watts and have been turning the roller inductor the odds are quite good you have damaged it through arcing. This can cause the meters to bounce around as you turn the inductor and can make them do very strange things if you happen to park the inductor on a spot where it has been damaged. Always make manual tuner adjustments at very low power! In particular, it will present such a high SWR to the rig that the foldback circuitry will prevent much forward power from being developed.

    It only took one slip-up forgetting to turn the power down to damage the roller inductor in my Ten Tec 238.
     
    AG5DB, WA7ARK and N3SE like this.
  9. N3SE

    N3SE Ham Member QRZ Page

    Ya internal Tuner is off and I agree with what you are saying dumb move on my end .
     
  10. WB5YUZ

    WB5YUZ Ham Member QRZ Page

    I wish I knew what to tell you. Try borrowing another manual tuner and see if the same thing happens. If it does, your roller inductor may be ok. If not, try connecting an analog VOM across the roller inductor and doing a continuity test.

    Good luck. Follow up if you get the chance.
     
    N3SE likes this.

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