of theHXfiles.
As I write this file it has been only a couple of weeks since the rally in Germany and I am still sorting out (the bills) the bits and pieces I bought at the Friedrichshafen show in June. As well as the many fittings that I bought, I also bought a 30 cms wide dish for 10GHz, (good for some local work) and a 20w amp for 23cms ATV. So, that will be another project to work on in the future for the /portable shack or/mobile.
Out, and about. |
| Photo 1 |
Since the last HX files I have been out and about with Mark EI9FX doing a bit of portable ATV on 10 GHz. Before I went /p, I went to Mark’s home to line up our sat receiver’s and to give the rest of the gear the once over to make sure that everything was still working after the last time they were used. As all of you portable operators know, it can be very easy to damage your gear from all the assembling and dismantling of the station. So a check up before you go could save yourself a wasted journey, after all just because the equipment was working when you packed it away, it may have been damaged in transit or even in your store room.
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| Photo 2 |
The first test to be done was for me to transmit from one end of the Mark’s garage
to the other. We used Mark’s 10 GHz Tx/Rx on receive mode. My first Tx was using a transition, which also had 12db of attenuation on it, see photo 3 above the 20 cent piece, as we did not want to be nuking our self’s. For the next test I got a 12v battery and I set up my station 30m from Mark’s station, and the third test was 200m.
I attached a small horn aerial belonging to Mark to the transition, and it did not matter where I pointed the aerial we got the same p5 results still with the attenuation attached. We then repeated the test with Mark’s 10 GHz doing Txing. And after all those test were done, it was time to find out if we could pack all the gear away before Pauline (Mark’s XYL ) would have the toasted sandwiches and tea made. I am happy to report that Pauline won, as the tea and grub were on the table when we went into the kitchen.
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| Photo 3 |
It was after 2300 when I was about to leave Mark’s QTH, and as I had all the gear in the car I asked Mark about a site I could operate from that was not too far away and that was handy for me to get to as I was unfamiliar with the area around his house. Mark knew of a spot that was on a small hill over 4 miles (7’ish km) from his home and we both knew that we would not be setting any records at that distance, but we had to start some were. After setting up the portable gear in the car, I used the transition with the horn aerial, and the attenuation still attached.I did not use any hi-tec stand, I opened the window of the car to a suitable level, and with the aerial and my hand resting on the window, I took aim roughly at Mark’s home, I gave him a call on 2m and as arranged he got his son Darren to turn the flash lamp on and off in the window of the shack he had set up upstairs in the east wing of his home. I turned on the rig, and after 2 or 3 seconds, (yes seconds, because we knew before we had even started to transmit each
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| Modded LNB's with wave guide type on left |
others location) Mark received my signal P5; I could turn the aerial almost 45 deg off Mark before my signal went to a P2. Mark’s report was so good I decided to remove the aerial from the transition, after I had turned the rig off first. When I transmitted again there was no difference in the quality of the pictures Mark was receiving. I was using a camcorder with a tape in it playing a previous event that was recorded earlier as this would give a better picture than a live one as the camcorder I was using on the night had not got an infrared option. Later on, after a couple of more tests ,and for the grand finale, I used the slot antenna you can see in photo 3. I used the ever popular cable ties to secure the aerial and transition to the roof rack. (no expense spared here). I then placed the camera on the dash of the car using some sticky back Velcro, and then using the lights of the car, Mark could then see the road ahead of me, and with the lights of the car turned off, (I had stopped the car at this time) he could make out the lights on the M1 motorway and that of Dundalk in the distance. Equipment used. Both Mark and I used the same type of transmitters for our tests. In the upstairs room Mark used a 40 cms dish first for receiving and he then switched to just an LNB, (photo 2), when we saw how strong the signal was. TX power was 500mw reduced down with 12db attenuation to around 30mw when we were in Mark’s garage. That is still very strong RF power in a confined space and with the chance of reflected power so we took care that we were not in the firing line of the RF. In photo 1 you can see the equipment I
used on the night; the picture was taken with the cables removed.
And finally…....
Many thanks yet again, to Thos (EI2JD) for taking the photos for me.
And may all your signals be P5.
73’s Pat.
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