Radio and rails...

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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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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