6M NOOB Propagation Question

Discussion in 'VHF/UHF - 50Mhz and Beyond' started by KC7RAD, Jun 16, 2019.

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  1. N9DG

    N9DG Ham Member QRZ Page

    Siting and monitoring only the 50.125 calling frequency and no having bandscope will cause you to miss working a lot of stuff that is otherwise workable. And now with the WSJT-X FT4 and FT8 modes, even more so.

    To really do 6M justice you really do need a radio with at least one good bandscope and waterfall, preferably 2, plus 2 or more receivers. One bandscope and receiver can watch/monitor and tune around the CW/SSB part of the band. And then another bandscope plus an additional receiver or two for the WSJT modes, all running at the same time. Been doing that the last couple summer Es seasons on 6M now. Has been supper effective at catching and working things across SSB and the WSJT modes. It has been wonderful never having to pick one mode OR the other, it has always been analog AND digital at the same time.
     
  2. WE4E

    WE4E Premium Subscriber QRZ Page

    While those are nice tools, it's important to understand how 6m behaves. Where to listen and when. If you don't, you will indeed spend a lot of time looking at and listening to nothing.

    An on the subject of bandscopes, they don't always tell the whole story. It's not uncommon for me to be able to hear something that doesn't make a mark on the bandscope. Admittedly, my scope could be better. It's a really fancy RTL receiver hung off the 9mhz IF out from my FTdx-5000, the latter of which is particularly good at digging things out of the fuzz.
     
  3. N9DG

    N9DG Ham Member QRZ Page

    But with a low enough cost SDR and bandscope like a RSP1A is, it doesn't cost much to let it run much of the time. Certainly during the month or so before the summer Es season begins in May ish to September or so. And then again around the winter secondary Es season. While a RSP1A is not top end, it is good enough for that kind of monitoring.

    One of my absolute requirements of the bandscopes is that they be able to see EVERYTHING that I can hear. If the radio can hear something that the scope does not display, then the spectrum scope / waterfall is simply not good enough. I'd scrap that spectrum display scope in that scenario and find something else. I need to have the confidence in my spectrum scope / waterfall to know that there are no hear-able signals where I don't see them. Anything less than that largely defeats the whole point of having spectrum scope and waterfall for weak signal work to begin with.

    In addition to scope sensitivity having a scope with good resolution bandwidth is also important. A spectrum display or scope that can only achieve a 50 Hz minimum resolution bandwidth is not good enough either. A 5 - 10 Hz or better resolution bandwidth I consider a minimum for that display performance metric. Also be able refresh at a 30 Hz rate or better. And refresh rates less than 10 Hz are downright painful.

    It is too bad that so little about those various spectrum display parameters are ever included in radio product reviews by various magazines and others reviewing radios. Some do publish data about those specifications, but many do not. All spectrum displays and scopes on radios are not created equal.

    I have one of those RTL dongles and it isn't truly that useful, once you have it's front end gain cranked up enough to actually see truly weak signals, it will crunch big time on only moderately strong signals. Even in IF tap applications. They at best only have a 50dB so of dynamic range. Simply not enough. Even the RSP1A is pretty limited for dynamic range, but in my experience is better.
     
  4. WA9SVD

    WA9SVD Ham Member QRZ Page

    I've only had experience with an IC-7300 waterfall display, but I can HEAR (and work) a lot of signals I don't see displayed on the waterfall. YMMV.
     
  5. WA9SVD

    WA9SVD Ham Member QRZ Page


    WE represent that statement. (Even if some of us are no longer "contesters.:("):rolleyes:
     

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