Amateur radio (250)

M0RVB

70cm FT8

My first FT8 on 70cm. Only 25km, but still a first for me. No reply sadly, so no QSO this time. At the time I sent a few CQs while watching pskreporter and seeing nothing. I checked this morning just out of interest and there was this one reception report. This was via the FT817 and 2.5W into a 70cm big wheel, which isn't at all big at that frequency! I had only just installed it which itself was a bit of a comedy of errors. I had some M&P cable ready for it but just never got round to making it up, so soldering iron out, BNC at the shack end, cable pushed through the hole in the ceiling, N male at the antenna end. The centre pin fell out! So, picture me managing to pull the loft end of the cable back down the ladder and across there landing floor to the shack (hard enough feeding the cable through the hole so I really didn't want to have to pull it put again!), supporting it with my knee, soldering iron at maximum reach and more heat... the NanoVNA showed the SWR to be just right where it needed…

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M0RVB

VARA HF and VarAC and USB fiddling

I had heard of VARA HF but not done anything about it because the Windows machine is not connected to the HF rig. That was cured yesterday by something I should have got ages ago - a USB switch. This switch has two USB connections aimed at connection to two PCs, and then four USB sockets for devices. So the SignalLink and the USB adapter for CAT control are now plugged into this switch which shares these between the Linux and Windows PCs. It all seems to work fine with USB devices connecting and disconnecting and, fortunately for Windows anyway appearing in the same place. It took me a whole to figure out that the CAT control, ends up as COM6 on the Windows box but so far it has not decided to change when reconnected. Now the Windows box can see the FT450D I tried WSJT-X - no issues there, and it provided a good end to end test. I downloaded VarAC and the VARA HF modem. Installation went fine and almost straight away it decoded a beacon on 14.105. Since then it has been decoding numerous other beacons and a few CQ calls but I have yet to…

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M0RVB

FT8 on the FT817

I did a bit of experimenting today with WSJT-X on the Mac and using the FT817. So far, so good. Ok, no surprises there, lots of people are doing the same thing! This is part of my master plan (I'm up to Plan G so far I think) which involves using the FT817 for VHF / UHF instead of the FT450D and transverters and switches, and being able to take the kit elsewhere, either in the UK or abroad. The only laptop I have is the rather old now 2013 MacBook Pro. Still my workhorse for just about everything, I tend to run it plugged into power and with an external monitor. But the battery still holds up for a good while. I wanted to get a Mac Mini because I always use the laptop with the screen closed, using a wireless keyboard, trackpad and mouse, and wired Ethernet. Mostly it works fine, just sometimes it manages to jumble the size and position of all the windows when logging into the thing. No biggie. But used 2018 Mac Minis cost a bunch, so I'll stick with this for now. WSJT-X went on just fine - again, no surprise there. On…

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M0RVB

FT817 upgrade

I plan to use the FT817 portable but also for VHF and UHF FT8 and other digimodes, so I wanted to upgrade the standard oscillator to the TCXO version (Yaesu's TCXO-9). But these are scarce, at least in the UK. I've searched for a while and got nowhere so I ended up buying one from Wimo in Germany as they had them in stock. The original TC1 unit (left) and the TCXO-9 (right) are, of course identical in size and sit on 7 pins. There are at least two variants of the TCXO-9 and I guess this one is the newer of the two. The unit is easy to install. Obviously - or it should be! - disconnect the battery, wear an anti-static bracelet or take appropriate measures, then the old unit simply pulls off of the 7 pin connections and the new unit presses in to replaced it. With the set back together and given a little time to warm up, and set up for CW it holds steady just 2 hertz high. That should be good enough for data modes!

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M0RVB

QO100 DATV reception finally

Well, that made quite a difference! I removed the POTY from the QO100 dish today and replaced it with a 'Bullseye 10kHz' LNB sourced from Amazon and advertised as a 'QO-100 Bullseye TCXO LNB'. It's just clamped in place with no attention to position or skew. Winterhill plugged in and instantly I see pictures. The LNB behind the POTY only managed negative values in the MER and D fields, this one seems too work rather well. No idea what happened to the old LNB but these things happen I guess. It's dry and had a waterproof housing. I've used the existing CT125 cable and connectors. Now to put the Winterhill box in a better location than just sitting on a ladder tied on with a bit of wire!! The above photo shows the Winterhill viewer and console on the left and the Quick Tune on the right, all working nicely.

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