RBNhole problems on 30m and during contest times?

Dear all:

Today, I planned a quick evening activation of DM/BW-484 (Bussen), a nice 8-pointer I can very much recommend for the scenic operating position near an old castle and view over much of Upper Swabia.
Of course, the 500m ascent - distance, not gain in altitude :wink: is not a real challenge. But Covid times require flexibility ;-).

Now, the first thing I noticed was heavy traffic on 40m; I had not checked for contests. After trying 7.031 down to 7.002, I thought 7002.6 was clear, called CQ (after two rounds of ? and QRL?), and was spotted by RBN quite quickly:

However, no callers arrived, and RBNhole did not create a spot from the RBN input. After a while, strong contest stations took over my frequency.

So I gave up and resorted to 30m in the hope of a relaxed evenly activation, called CQ at 1555Z and was again spotted quickly by RBN:

@UR4EZ answered my call at 1602Z but did not seem to understand my request to spot me, so he was likely not interested in SOTA.

But still no SOTA spot from RBNhole / RBNgate.

After 10 minutes of trying 30m, I QSYd to 14060.2 at 16:06Z, and again, RBN picked up my 5 W signal quickly - with a surprising 48 dB from @W1NT-6:

Only after that third spotting from RBN did RBNhole / RBNgate create a spot for me:

and quickly @DJ5AV, @AK8A, @AB4PP and @EA7GV came to my rescue.

What was planned as a walk in the part was a much harder fight to secure the eight points.

Now, my main question is - what went wrong? Why didnā€™t RBhole/RBNgate spot me?

As far as I can see, my alert was correct:

My guess is that RBNhole/RBNgate was overloaded by the content-based flood of spot data. But why did it work on 20m but neither on 30m nor 40m?

Thanks for any insights!

73 de Martin, DK3IT

Paging Andrew @VK3ARR.

Iā€™m actually on call working this weekend, and those words made me jump out of my skin :slight_smile:

Looks to be a bug in the handing of the stream from the RBN.

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@VK3ARR Donā€™t feel pressed in any way - I am very, very thankful for all the energy you have been putting into the tool, and I know it is just a hobby and service to the community!
Have a peaceful holiday season!

73 de Martin, DK3IT

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All good, just pushed the fix :slight_smile:

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Thanks a million! In case you find the time to explain what went wrong I could try to send some good karma on a wavelength of your choice :slight_smile:!

The actual commit is here:

Basically, the buffering from the telnet client is such that you canā€™t always guarantee you have a full line or sometimes youā€™ll have more than one, and the telnet client doesnā€™t seem to work nicely with any of the buffering libraries in rust, so I spun my own quickly. The issue was what to do with the bit left over in the buffer that doesnā€™t processed. In my case, I pushed it onto the previous string, but that string wasnā€™t as empty as I thought it was, so rather than pushing, I replace the string.

When I tend to do RBNHole testing itā€™s usually during the APAC day when things arenā€™t particularly busy on the network, so you donā€™t see much issues with buffering. That goes out the window during US/EU times, and when I went back through the logs, I could see plenty of instances of broken buffering, which meant I could pinpoint the issue.

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Thank you Andrew!

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If I could have a Ā£1 for every time Iā€™ve had to tweak buffering code for corner cases or when assumptions were not quite so valid as I thought then Iā€™d be a very rich man! Itā€™s worse when the system appears to be working very well the way RBNhole has been.

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Hello,
First, thank you very much Andrew @VK3ARR for your work. Second, Nice to chase you Martin @DK3IT , and rescue your activity. Third and last, contest weekend, better only WARC bands, we cannot with small guns survive the big guns.
Take care.

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Iā€™m very new to all this, only having just recently got on the air. I was amazed how busy 20m was yesterday compared to mid-week and today was manic. I came across the word CONTEST on more than one frequency. Trying to find a quiet spot to try the RBN was a struggle and I gave up after a couple of attempts as I was worried my clumsy attempts might be drowning others.

I am amazed the RBN worked at all with such noise* going on.

The good news was I heard a CQ call from Granada in Spain and it was slow enough even I could read the callsign. :slight_smile:

*. Sorry, traffic. :slight_smile:

Do you know if there are any plans to have FT8 signals spotted through RBN when they call ā€œCQ SOTAā€?? Thanks! Lance W7GJ

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Yes, thereā€™s plans, but itā€™s about 20 on the list of priorities right now :slight_smile:

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Thanks so much! I think that would be a big incentive to using FT on SOTA activations! GL and VY 73, Lance

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