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TS-530S Tuneup & RF in Shack

Discussion in '"Boat Anchor" & Classic Equipment' started by KB1RHB, Dec 10, 2019.

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  1. KB1RHB

    KB1RHB Ham Member QRZ Page

    I replaced the Cathode R's then confirmed with a measurment, its right on to ~ 2%.

    I ordered the Kit in the article, and will test all the parts I extract just to see if there
    was actually a problem.

    My driver tube tests good but I have seen articles tube tester results may not
    always insure good operation in circuit.

    I will check out the rest of the signal path as you suggest.

    Thanks as always, help very much welcomed.


    Regards, Dana.
     
  2. K7TRF

    K7TRF Premium Subscriber QRZ Page

    Here's another good article on Kenwood hybrid final stage troubleshooting and repair that also gives methods to measure the fixed loading capacitors switched in on each band.

    It doesn't sound like you have driver tube problems since you're able to achieve rated or near rated plate current on the higher frequency bands. Basically if you can peak the Preselector/Drive control to achieve at least decent swing of the ALC meter without having to crank the Carrier control all the way up then your driver tube is fine. Your chart showing 2/3 ALC range for all bands isn't completely clear but if you can get 2/3 of full range meter swing in ALC mode and especially if you're not maxxing out the Carrier control to get that meter response then your driver tube is fine.

    Definitely do that. Basically any break in the output signal path can lead to symptoms similar to what you see where the DC input power of the rig is near what's expected but the RF output power is very low. Similarly problems in the output wafer of the band switch that switches the inductor and switches in the fixed loading capacitors on various bands can also lead to problems like you're seeing. That article linked above gives you capacitance measurements that you should see on each band as those fixed loading capacitors are switched which could be part of your troubles. A careful visual inspection of that bandswitch wafer could also give you clues for instance if contacts are bent or the switch contacts are charred.
     
  3. KB1RHB

    KB1RHB Ham Member QRZ Page

    David I must be blind bu the link in prior post I do not see for the article.


    Regards, Dana.
     
  4. AI3V

    AI3V Ham Member QRZ Page

    Can you adjust the load control for 225 ma at the plate dip?

    Either yes or no.

    If yes= you are tuned, and delivering rated rf power (regardless of what the wattmeter says) into your antenna system

    If no= you are out of range of the "pi" network in your transmitter, and you either need to add a external matching unit, or adjust your antenna untill you can adjust the transmitter for 225 ma at the dip.

    Also, if you cannot adjust the transmitter for 225 ma at the dip into a dummy load, you need to fix your transmitter.

    If you don't have a dummy load, you are wasting everybody's time.

    Rege

    Forget the "wattmeter" readings, your watt meter is a rf voltmeter calibrated in watts INTO A 50Ω LOAD.

    and you have $pent money to find out you don't have a 50Ω. Load, and the inability to tune the transmitter to 225 ma at the dip, like you can into your dummy load allready told you that.
     
    Last edited: Dec 15, 2019
  5. KB1RHB

    KB1RHB Ham Member QRZ Page

    As noted in the excel spreadsheet all measurements were into a dummy load, bias set for 50 mA.

    No. Spreadsheet shows the Ip when optimizing per the tune procedure I used
    found on manual/web by several users.

    I think there are problems in 530, am going to use a VNA to look at key components soon
    as K7TRF recommended soon.


    Regards, Dana.
     
    Last edited: Dec 15, 2019
  6. K7TRF

    K7TRF Premium Subscriber QRZ Page

  7. AI3V

    AI3V Ham Member QRZ Page

    Good luck to you, you have multiple problems to sort out, and your measurements make no sense.

    Rege
     
  8. KB1RHB

    KB1RHB Ham Member QRZ Page

    Making some progress.

    10M definitely a problem for work. Looks like a faulty component with a lot of ESR in it ? In plate
    current tank circuit ? Possibly band switch.....Finals crapping out....

    Seems odd to me that 160, 80 are lower output than rest of bands. And looking at 40M its developing
    good power but at significant lower plate current than say 20M. I guess for greater losses, for same
    power, we need more Ip, reactive circuits more loss.....

    Then there is 160M where its Ip >> that 80M, for roughly same power.....?


    upload_2019-12-23_15-45-4.png



    Just noticed after some more time elapsed all the power numbers dropping, but HV
    is hanging in there around 900V. Dummy load still cool. 40M dropped off to 35W.


    Regards, Dana.
     
    Last edited: Dec 23, 2019
  9. KB1RHB

    KB1RHB Ham Member QRZ Page

    Checked the 12BY7 in a TV7, its trans-conductance almost twice spec.


    Regards, Dana.
     
  10. KD2ACO

    KD2ACO Platinum Subscriber Platinum Subscriber Life Member QRZ Page

    Ok! The fact that the radio is putting out decent power at 160, 20, and 15m means that the by7 is ok.

    Have you gone through the alignment procedure as spelled out in the manual in the proper order of the steps? I looked through the thread and haven’t seen if this has happened yet.
     

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