Power for FT8

Discussion in 'Working Different Modes' started by HB9DDS, May 22, 2021.

Tags:
?

Output Power FT8

Poll closed Jun 21, 2021.
  1. 1W

    1.5%
  2. 1-10W

    10.4%
  3. 10-25W

    14.9%
  4. 25-50W

    32.8%
  5. 50-100W

    22.4%
  6. 100W and more

    17.9%
ad: L-HROutlet
ad: l-rl
ad: MessiPaoloni-1
ad: L-MFJ
ad: abrind-2
ad: Left-2
ad: Left-3
ad: L-Geochron
ad: HRDLLC-2
  1. N3RYB

    N3RYB Premium Subscriber QRZ Page

    You know, maybe I enjoy getting +15dB reports back from ZL stations on 20m FT4. 8600 miles. Probably was running 300W. Completed the QSO in the minimum number of cycles. No repeats. I used enough power to accomplish my QSO effectively. Then I was off the air, leaving spectrum for other folks. Not endlessly repeating because the other guy can't hear me.

    As a QRPer you of course get the satisfaction of knowing you did it with very little power. Me? I get the satisfaction that I'm making contacts around the world with antennas that I made and amplifiers that I repaired and restored to functional order. Restored because I specifically wanted to use them for FT8. And you know what? I learned a whole heck of a lot in the process. Also I don't want to hear about the "spirit" of CFR 97.313. It's there, there is no "SPIRIT" to law. There is a massive amount of interpretation left to be found. That said, take me to court for using "too much power" with FT8 and violating CFR 97.313. None of my equipment is remotely near legal limit.

    There is more than one way to be an amateur radio operator, your way isn't any better than mine. Just different.
     
    WD4ELG likes this.
  2. N3RYB

    N3RYB Premium Subscriber QRZ Page

    Additionally here is a fun little screenshot from pskreporter. I was running about 350W on 20m FT8 at 3am here. Have a look at which stations from the US were heard in QF56. That I was able to work. Anything less than that just wasn't getting the job done.

    [​IMG]
     
    WD4ELG likes this.
  3. KQ8W

    KQ8W Ham Member QRZ Page

    I’m sure that’s the reason. Lol

    I don’t see many threads about the power used for other modes.
     
  4. N6YWU

    N6YWU Ham Member QRZ Page

    There may be a reason for that.

    FT8 can be accurately decoded at well documented experimentally validated (and very low) S/N levels. If you have an estimate of current propagation conditions and path loss, you can reasonably estimate how little Tx power might be needed to have a good probability of "carrying out" the desired exchange with some given party. And only a few dB more is needed to increase that probability significantly.

    However on CW, SSB, and especially AM modes, it probably requires vast amounts of Tx power to barely wiggle the eardrums of some huge portion of aging operators enough to "carry out the desired communication" regarding their current health problems, last surgery, and etc.

    I guess that some people are assuming that WSJT-X software wasted too much of its youth at rock concerts, wrenching hot rod engines, jackhammering tower foundations, etc. and is just as hard of hearing as they are. Crank up the linear.
     
    K1BQY and WD4ELG like this.
  5. WD4ELG

    WD4ELG Ham Member QRZ Page

    "How much power should I use on FT8?"

    "Smoke 'em if you got 'em."
     
    NM9K likes this.
  6. WG7X

    WG7X Platinum Subscriber Platinum Subscriber QRZ Page

    Get out the hair shirts, boys! It's Monday and there's another "Do ham radio my way!" FT8 thread in progress!

    Referring back to FT8: I don't really care how much power another ham is using. I DO care about over driven signals that take up way to0 much of the "watering hole"!

    Was on ten meters today. Only activity I saw was on the dreaded FT8 watering hole at 28.074. Boy's (and girls) you've never seen so many crappy signals! A couple of them were taking up most of the normal "band width". Were they using excessive power or excessive audio? Judging by the signal strength, I'd go for crummy audio. Only one guy had a crummy signal that was way over +00. It turned out that he was just over the hill from me. Put in attenuation up to the max, and he still had a crappy signal.

    I wonder if he will ever figure out why none of the stations he was calling were responding to him? It was not just my receiver as I thought at first: he had a genuine crummy, over driven signal.

    So there it is: audio quality and clarity will probably go a lot further than higher power. Having said that, I repeat: I don't care how much power that you run, just do it cleanly. That's true of any other mode you run, not just digital.
     
    WD4ELG and N3RYB like this.
  7. N3RYB

    N3RYB Premium Subscriber QRZ Page

    Tell me the estimate of how much power I need when I'm calling CQ DX?
    You know what those guys are doing though? They're on the air, using their radios, having conversations with their friends. They're not waiting around endlessly for the sunspots to show up.
    I guess some people would rather whinge on the internet about how other people are doing ham radio wrong.
     
  8. N6YWU

    N6YWU Ham Member QRZ Page

    Unfortunately that helps encourage an arms race. Some operators with clean rigs operate QRO when not really necessary. Then other (and worse, brand new) hams with less properly configured setups (overdriven modulation, etc.) do the same to compete for QSOs. And you end up with more splatter covering the new hams trying to do QRP SOTA, or whatever, on the currently tiny slice of FTx per band.

    Sure, the guy who wanted CQ DX to India, QRO. Fine. I'd do that to if that were my primary interest. But if that guy then answers a much closer station at the same Tx power, his signal is likely still covering up some poor operator far away in India, et.al., far from his current contact. The mobile cellular (and WiFi, et.al.) engineers learned long long ago that dynamically managing the Tx power allowed more people to talk on the system at any one time.
     
  9. WG7X

    WG7X Platinum Subscriber Platinum Subscriber QRZ Page

    So. You have a way to prove that? Ham radio is not an arms race. There will always be someone out there who has better ( stuff, land, XYL, whatever) what of it?
    If you consider ham radio as a race, the only conclusion I could reach would be that says a lot about your perspective.

    So, back to that unsupported conclusion: how, exactly, do you determine another ham's power level? Especially in a mode like FT8 where there are few if any clues provided?

    Big signals can come from something other than just pure power output, you know...

    Last point: How do you determine when it is necessary (in your opinion) to operate high power? Corollary question would be: where exactly is the level set? 100, 500, 1000 watts?
     
    N3RYB likes this.

Share This Page