Ft-450d psk trouble

Discussion in 'General Technical Questions and Answers' started by N5OUR, Aug 7, 2020.

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  1. N5OUR

    N5OUR Ham Member QRZ Page

    Hello all, I’m having trouble adjusting my settings for psk. I’m running a donner digital interface with my ft-450d into an external sound card on a win10 pc. I’m using flrig as control for both WSJT-x and fldigi. With WSJT-X and ft-8 I seem to get a clean and stable signal out but with psk31 on fldigi it seems off and my signal reports while strong are not clean. It doesn’t seem to matter if I run 10w or 100w, my power meter rapidly goes up and down but is always just a fraction of what it should be. For example even at 100w, power out rapidly jumps from about 10-50w. That’s with high ALC. if I adjust to no ALC (like directed) power out decreases to about 20w but still jumps rapidly. Maybe the needle is supposed to wiggle with psk but I don’t remember it doing it with other radios. Any thought would help
  2. PY2RAF

    PY2RAF XML Subscriber QRZ Page


    While I don't have a FT-450, wrt High ALC, low TXPO. Have you checked the SWR meter at this point? This sounds pretty much like high SWR.
  3. N5OUR

    N5OUR Ham Member QRZ Page

    Sorry. Should’ve mentioned . Swr is completely flat 1:1
  4. KL7SG

    KL7SG Platinum Subscriber Platinum Subscriber QRZ Page

    Is your watt meter set to read peak power?
  5. N5OUR

    N5OUR Ham Member QRZ Page

    My watt meters are just the ones on my mfj tuner and the one on the 450. Both pulse the same way.
  6. KL7SG

    KL7SG Platinum Subscriber Platinum Subscriber QRZ Page

    What model of MFJ tuner do have?
  7. KL7SG

    KL7SG Platinum Subscriber Platinum Subscriber QRZ Page

    I am not positive; but, I think the FT-450 indicates average power.
    Your radio has about a 100 Watt PEP transmitter. If you are transmitting a single tone, it would indicate about 100 watts (such as key down CW).
    In all other cases it would probably indicate much less than 100 Watts.

    Anyway, I am interested in the MFJ tuner model. The reason is, it may have a peak reading wattmeter
  8. N5OUR

    N5OUR Ham Member QRZ Page

    It’s a mfj 962b. It doesn’t have a peak reading. I’m curious why you’re asking though. With my other rigs, psk always seemed to have a stable transmission output unless something was off. That’s why I asked the initial question.
  9. KL7SG

    KL7SG Platinum Subscriber Platinum Subscriber QRZ Page

    I ask so I can have a better understanding of the xmiter power signals you seeing.

    I use a Pro III and with the output power set to 30 watts (average), the output power fluctuates between about 20 watts to 30 watts.
    I consider this to be normal. With higher transmit power the swing(s) will be greater.

    More questions:

    Are you using any kind of audio compensation, speech compression ...
    Does your sound card provide any audio compensation or audio gain compensation such as bass boost or treble adjustment?
    When you adjust your audio input level, do you do this with the Mic gain or the computer sound card?
    By any chance, is your computer sending beeps or other sounds to the sound card that are not related to the signal you want to send?

    I set my audio levels on a Pro III as follows:

    1) All unwanted computer generated sounds are off. (Beeps ...)
    2) Rf power set to between 10 to 30 watts
    3) Mic Gain set at about the 10:00 position (you can increase mic gain if needed to so as to show a little ALC)
    4) Sound card audio levels set to just show slight ALC or slightly below the ALC threshold.

    I am sure there are other ways to set up your system, this just works for me.
  10. KL7SG

    KL7SG Platinum Subscriber Platinum Subscriber QRZ Page

    i just looked at the FT-450 manual and it shows a speech processor (for Mic gain) and a mic equalizer.
    You might want to try setting the mic gain to low and the equalizer to flat using the ft-450 menu settings.
    This would eliminate the speech processor and equalizer as causing the problem you are seeing.

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