Amateur radio (250)

M0RVB

Rather obvious EMC problem...

I noticed just now that the Raspberry Pi that runs my ADBS receiver and also has '1-Wire' temperature sensors for the central heating registered a pipe temperature of a theoretically impossible -1700C. Oh, did I mention that my 20m / 6m dipole is in the loft... and the Pi is in the loft... about 2 feet from one leg of the dipole... Hmmm. I can see a connection here given the timestamp was the same as a JT65 transmission.

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M0RVB

JT9 blues

I've had a couple of JT9 attempts these past two days on 20m where I've answered a CQ and received a signal report back, and sent mine but then received the same -nn signal report again. And again. Presumably the remote station has not been able to decode my reply. So I never get to the 73. I'm guessing the band just fades away from underneath me... If I remember right it was the same remote station each time. I've had successful JT9 QSOs so I am putting these down to bad luck and I hope the other guy isn't getting frustrated!

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M0RVB

JT9

Well another first for me tonight, a JT9 QSO, and on my second attempts at answering a CQ. This was with a USA station apparently over a 5,600km path. But again the replies come in the Band Activity window on a different frequency. Not sure what I am doing wrong there, but this was a complete QSO 'by the book'. Edit: I never did follow up on this post. This is, of course perfectly normal operation, for example where someone sits on a quiet part of the segment but listens across the whole.

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M0RVB

JT65 - mostly

I spent a couple of hours yesterday with WSJT-X trying to make some contacts by answering CQs and getting nowhere. After a lot of fiddling with settings (I spotted the ALC on the FT450D was going haywire - who'd have though it had a display!) I now have much better settings of sound system output and Tx control on the SignaLink. The Tx is now set to just below to 9 o'clock position, so almost to the third tick mark, and the sound system output is set to 29% via the Pulseaudio volume control. The power setting in WSJT-X is set to -0.9db at which level the signal still triggers the PTT relay in the SignaLink but at 100% (-0db) the ALC triggers. But no luck with answering CQs. Actually the Pulseaudio setting threw me at first because WSJT-X uses ALSA, but the ALSAmixer shows the same 29% as set by Pulseaudio so I'm not fussing. Also, it still gives the expected power output on the PS modes and a test call on BPSK31 worked fine, so it's all be written down. And today I got a reply to my reply to a CQ. But it was confusing. WSJT-X has two…

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M0RVB

PC screen real estate...

One thing I've noticed is the screen required for these digital modes. I have a 22" 16:9 screen and I had a secondary 19" 4:3 one attached when I was writing my Ph.D. but it generated a load of RF hash. So now I just have the 22" and it's not big enough! Many shack photos show dual screens or even dual PCs and multiple screens and I can see why. Ok I have the MacBook for logging and other things, but the shack PC desperately needs more screen size and/or more screens. Something else to work on. Unfortunately the PC is a scrapper that has no HDMI output so I am limited to a DVI and a VGA screen. Hmmm... so I need a better PC too... I am just beginning to experiment with JT65 having set up WSJT-X recently and the screen is full.

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