Back on 10 Meter FM

I have been hearing everyone rave about the improving conditions on the HF bands, especially some great propagation on 10 Meters. Then I came across this posting by G4VXE: The Return of 10M FM. Ah, yes, I do recall having a blast running FM on 29 MHz years ago!

This triggered the thought that the FT-8900 transceiver in my car has 10 Meters in it. Lately, I have been using this quad-band FM rig (10M, 6M, 2M & 70 cm) like a dualband 2M/70cm rig. I almost forgot that it had the other two bands. I plopped a 10 Meter Larsen antenna on the SUV roof and reconfigured the coaxial cables and diplexers to get the right RF to the antenna. Suddenly, I was back on 29.6 MHz FM calling CQ. K8LF (Jerome, mobile in Virginia) came back to my call and we had a nice little QSO.

10M FM is a little bit counter intuitive (some people would say “makes no friggin’ sense at all!”). Here we have a high frequency band which can introduce fading and phase distortion (that destroys FM signals) being combined with our most inefficient modulation format (FM). Why on earth would anyone mess around with this combination?

I think FM is fun on 10 Meters for the same reason it is fun on VHF and UHF. You can be tooling down the highway with no radio noise at all and if the band is open, a signal pops through the squelch. Forget all of the static and Donald Duckness of SSB communication. When the signal is strong, FM is loud and clear.

Its good to have 10 Meters back again!

73, Bob K0NR

3 Replies to “Back on 10 Meter FM”

  1. Hi Bob,

    I’d been very similar with my use of the FT8900! Hope to work you on 10m FM soon!

    Vy 73, Tim G4VXE

  2. Hello there fellow HAMS.
    I have never listened to 10FM and I am normally working SSB ON 10M.Surprisingly with the solar conditions improving this year was playing on my radio and changed the mode to FM and I was amazed to listen to a QSO between a station in Greece in QSO with a station in USA on 29.60? I was copying both stations on 59+?
    I was thrilled since this the first time for me to hear FM on 10 M.I thought it was not possible.
    However , tried to call the station on Greece , he was able to hear me , but could not confirm my contact .He replied back (BAD MODULATION)?
    I could not understand the reason for that. I was pushing 95 Watts of power through my audio system and my Antenna is 7 Element Yagi Tribander and normally my signals are very loud in NA and Europe.
    I shall consult your technical experience in the type of Antenna I have used? Is it is suitable for 10M FM Transmission?
    Do I have to do some special settings for the 10 FM or AM transmissions. Please advise.
    Best Regards
    Salah
    HZ1SM

    • Salah,
      Your antnna should have no effect on the quality of modulation. I’d suggest reducing your mike gain to see if that has any effect. Also, you could try reducing output power.

      Bob K0NR