Configuring my TH-D72A for Satellites

Discussion in 'Satellite and Space Communications' started by KM6KCM, Sep 4, 2017.

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  1. KM6KCM

    KM6KCM Subscriber QRZ Page

    Hi all,

    I've been attempting to use a Kenwood TH-D72A for satellite communications for the past few weeks. I've had one successful QSO via SO-50, but I suspect that my TH-D72A isn't configured optimally.

    I'm using an Arrow 146/437-10 yagi with the duplexer, and a Heil HTH-K headset. I use Heavens-Above and AmsatDroid on my phone to track satellites, and do not normally have problems finding and hearing SO-50 and AO-85 as they pass overhead.

    I'm concerned that I may have my A and B bands set up incorrectly for working these satellites (recognizing that the A band is somewhat more sensitive on this HT(?)) and also that my audio balance between A and B may not be set correctly. Specifically, I believe that I should be able to hear myself repeated back from the satellite on my listening channel ... but I have yet to.

    Here are my frequency and channel setups:

    For SO-50:
    • Band A (RX, since more sensitive):
      • UHF receive frequencies (436.10 to 436.780 for different points in the pass);
    • Band B (TX):
      • VHF: 145.850 w/ a 74.4 tone to wake, then 145.850 w/ a 67.0 tone throughout the pass.

    Using this setup, I believe that my audio should be 100% balanced to Band A, with squelch off (Band B would be squelched). Or should the audio be split 50/50 between Channel A and Channel B? Duplex mode would be on, of course.

    Thanks all in advance for helping out with this. I've attached a screencap of my programmed frequencies, if anyone is curious. Tones aren't displayed for whatever reason.

    -- Dan KM6KCM

    Attached Files:

  2. WD9EWK

    WD9EWK Ham Member QRZ Page

    When you make band (VFO) B the active VFO, do you see the square with the T on the display? This would show that the VFO is all set to transmit the PL tone. Do you have DUP on the screen when band (VFO) B is the active VFO? This has to be on the screen for cross-band full-duplex to work, and will never be on the screen if band (VFO) A is the active VFO.

    Using a TH-D72A to work FM satellites, like using Kenwood's previous TH-D7 and TH-D7(G), requires some work switching between VFOs when using the satellites with a 2m uplink like SO-50. It's a little easier when the FM satellite uses a 70cm uplink, like AO-85, where the frequency adjustments are done in band (VFO) B used for transmitting.

    I have some files, including an MC4 file with a copy of a configuration from my TH-D72A, along with some other information on using this radio on satellites (voice and packet). You can go to and look in the TH-D72A folder for those files.

    WE4B likes this.
  3. KM6KCM

    KM6KCM Subscriber QRZ Page

    Awesome, I'll download and check out the MC4 file!

    I'm reading your tips closely and walking through the steps you've mentioned. Thank you so much!

    EDIT: What a cornucopia of cool materials in your Dropbox! I'm definitely going to poke around.

    How are you recording audio from your HT? Right now, I'm using putting my phone in my chest pocket and speaking loudly, but, obviously, I'm not able to record my received audio that way.
  4. WD9EWK

    WD9EWK Ham Member QRZ Page

    Using a recorder or an app on your phone in your pocket is one way to go. Just make sure to say the other station's call sign during each QSO, and from there you would have a record of who you worked and the time for each QSO.

    I don't use a headset with my HTs for satellite operating. I'm usually holding the HT and using the mic element in the faceplate of the HT, and go with an earpiece plugged into the speaker jack to hear the downlink. Going this way, I can use an audio splitter to feed the downlink audio to that earpiece and (through a short patch cable) an audio recorder. I prefer to use a small recorder than an app on a phone or iPod for my recordings - smaller than the phone, and I might be using the phone to track the satellite with an app on the display. I could run multiple apps on the phone, but I like having the recordings kept off the phone. Many (most?) audio recorders now use MP3 as the native file format, and either come with a USB connector or cable so the recorder can be plugged into a computer so the recordings can be pulled off the recorder.

  5. KG4AKV

    KG4AKV Ham Member QRZ Page

    FWIW, I just save the uplink and downlink in memory and transfer them to the appropriate VFOs. Then I adjust the VFO manually for doppler (tune up two "clicks" to .805 before the pass). Not sure if you're using memories to adjust for doppler or the VFO, but I know the VFO works. Not sure about the memory method.
  6. KE8FZT

    KE8FZT Ham Member QRZ Page

    I use a D72, and I program the memories. I sometimes forget to adjust for doppler, or where I am at, or that AO-85 adjusts up on TX, and SO-50 adjusts down on RX. Band A for RX, squelch wide open, duplex on. Band B on TX. 320 is the wake up for SO-50. Here is what my channel list look like for AO-85 and SO-50:

    Location Name Frequency Duplex Offset Tone cToneFreq
    300 ISS VHF 145.825 0 Tone 88.5
    310 AO85Rx 145.98 0 Tone 88.5
    311 AO85TxA2 435.16 435.16 Tone 67
    312 AO85TxA1 435.165 435.165 Tone 67
    313 AO85Tx 435.17 435.17 Tone 67
    314 AO85TxL1 435.175 435.175 Tone 67
    315 AO85TxL2 435.18 435.18 Tone 67
    320 SO50WaTX 145.85 145.85 Tone 74.4
    321 SO50TX 145.85 0 Tone 88.5
    322 SO50A2RX 436.805 split 145.85 Tone 67
    323 SO50A1RX 436.8 split 145.85 Tone 67
    324 SO50RX 436.795 split 145.85 Tone 67
    325 SO50L1RX 436.79 split 145.85 Tone 67
    326 SO50L2RX 436.785 split 145.85 Tone 67

  7. WD9EWK

    WD9EWK Ham Member QRZ Page

    How did you get TX and RX frequencies in different bands for those memories? AFAIK that's not possible with the TH-D72. I've only been able to use RX and TX in the same band, which differs from many Yaesu HTs and most of the Chinese-made HTs.

    NJ4Y likes this.
  8. KE8FZT

    KE8FZT Ham Member QRZ Page

    I use chirp to program it, thats the first few fields from the export file.
  9. WD9EWK

    WD9EWK Ham Member QRZ Page

    Does the radio work with the memories set that way? The Kenwood MCP-4A software and the radio itself (if programming from the keypad) won't accept memory channels set that way.
  10. W5PFG

    W5PFG Premium Subscriber QRZ Page

    Neither will the RT Systems software. I suspect it's just a Chirp interface anomaly.
    NJ4Y likes this.

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