Amateur radio (250)

M0RVB

QO100 next steps...

As I said before I want to use an actual transceiver for QO100 work rather than the Pluto. A precursor to that is a 2400MHz transmit capability and so I now have a nice new (used, new to me) SG Labs 13cm transverter, complete with the PCB log periodic antenna. It is already set up for the correct frequency range and seems fine... so, the next step is move the dish, clear the loft in that area, and get the kit up there. The transverter claims to put out 2W so I can use the existing AMSAT UK PA via an attenuator (max input is 200mW) which should get me 4 to 5W to the dish and has been adequate in the past when using the Pluto. I will first try with just the 'raw' 2W and see if I can get into the satellite. The eventual aim is to use an 80W PA I have ready so I can use DATV as well as SSB or digimodes - that also takes 200mW input - but as yet I don't have a suitable PSU.

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M0RVB

QO100 DATV attempt

Well this got off to a bad start! Ahead of my plan to move the QO100 disk so I can get the electronics in the loft rather than the garage I wanted to test out the Winterhill box to see if I could pick up any DATV on the wideband transponder. The Winterhill box generates the 18V necessary for the LNB so in theory it was just a matter of pulling the coax feed from the bias-tee in the garage and putting that into the Winterhill. That done, I could see the occasional signal but never a picture. Now, I had noticed that the NB beacon strength had dropped a while ago so today I decided to adjust the dish in case it had been knocked. That snowballed! I needed a laptop so I could see the signal strength while at the dish (remember the dish is on the garage wall currently at about 6 foot, so easy reach). Of my two laptops one is a Mac and had no SDR software, the other a Samsung Netbook running Ubuntu and terribly slow. I tried setting up several SDR packages on the Netbook and failed miserably. At this stage I need…

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M0RVB

FT817 first fiddle...

I now have a second Signalink USB complete with the Yaesu cable to go with the FT817. This is actually the third one to arrive here, the second was mis-advertised as having the radio cable - it didn't so it is going back because the price is £20 more than a competitor, a little less than the cost of the radio cable. Serves me right for trying to save a couple of quid! Anyway, FT817 and Signalink all cabled together and no antenna. Hmmm. Ok let's try into a dummy load, should be good enough for across the shack with FT8 running on the Linux box. Nothing received. Ah, it's a Windows box and 1.5 seconds adrift. Sync the time. No change. Ok. Set WSJT-X to 2m and use the front antenna which I have. Nope, nothing sent. It is always a good idea to read the manual before fiddling! Let's change the display to power. Ah. No power... Hmmm. Ok, transmit from the Linux box and I can see that on WSJT-X via the FT817. So it receives fine. Did I mention the manual? Set radio to DIG. Works fine now! Funny, that.

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M0RVB

To switch or patch...

I like to fiddle with stuff but getting antenna a to whatever-it-is b is complex and usually messy. Coax to the loft is all RG213 or Westflex 103 and tends to be a bit stiff and unwieldy so sits attached to whatever transceiver or transverter it was originally put in for. But mixing and matching is my aim. Switches would be equally complex I think. So I am eyeing up a BNC patch panel I used to have in a Land Rover for antenna patching and which has been sitting for 20 or so years sulking in a box of tools. It has 32 holes each designed to take a BNC-BNC through adapter which makes for an extra plug at the rear - maybe a BNC socket wired to whatever kit it is intended for rather than the rear socket would be a better idea. It is the wrong shape of course, better for 4 rows and less width as it makes for long patch leads but if I have all the antennas in the centre I can cut that down - sensible routing is a must. I will still need at least one switch but I have a good…

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M0RVB

Mobile?

One thing I am not good at is actually getting on the bands and taking. I tend to dwell on FT8 due to rather naff hearing, but this POTA / SOTA thing has caught my eye now and so I wanted something other than an FM handheld. Enter a used FT817 - not the ND but hey. Yes it is yet another thing to learn but it came with a rechargeable battery and gives 2.5W out on 2m into a dummy load (very quick test, you know, new thing, gotta fiddle!) which the manual says it will set itself to when on battery. Unfortunately I got this a few days after our last excursion which would have been an ideal test. It also came with a cigar-lighter charge lead so it can be charged in the car on the way to somewhere. The rig is smaller than I had imagined, very luggable. It's dwarfed by my SWR meter - I really need to get a smaller one for portable use. I reckon it will be very useful for when I eventually finish off my various microwave kits. On order is a CAT / USB lead. It came with a Bluetooth…

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