Yesterday and today I spent some time to make the front and back panels for the openASC box. I also did the panels for the boxes that Teemu, SM0W at SK0UX will assemble to use on their station. For myself I milled for 5 boxes so a total of 18 panels where engraved and milled, which takes some time to do.

The gray panels will have black paint filled into the engraved text, to make the text very well visible. We tried to mill black front panels but I still consider the gray ones look better because of everything gets too black otherwise.

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I have done some work on the power meter pickup that we will use at the station. I have re-thought my earlier design a bit so instead of having the log-amp + A/D conversion happening in the box located in the shack it happens “in” the pickup and all data is transfered on a openASC bus. However I think I will run a separate bus for the power meters just to not overload the openASC bus with data. This way I can hook up several pickups on the same bus and have just an openASC USB-dongle connected to the computer. So I don’t need to build the display units for each operating position, I can just run a PC software to display the info on position 3 and 4 for example. I will try to build the display boxes for the SO2R position (radio 1 and 2).

I have done some work on the display software for the PC, which will also make it possible to read the power remotely. It is written in QT and is therefor platform independent.

I will post some results when I have done some measurements on the pickup. I could not find any good boxes so I built one myself and I think it looks pretty good considering it was done in an hour or two.

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I’ve done some more work on the electronics at the station. Now I am trying to finish up the driver modules which will control the antenna switch system. These cards will sit in a room in the basement of the house connected to 2 pcs of 60 leaded cables which leads into the barn in a separate room which will contain all antenna switches.

There are a total of 80 source outputs and 40 sink outputs which are controlled over the homemade openASC bus which works very much like the old coax Ethernet bus.

I will try to finish up this during the week so I can maybe install this within a few weeks at the station. I will also try to finish up the antenna switch boxes so that system is installed before the snow goes away, because then it’s time for antenna work.

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A while ago I designed a power split which has got 7/16″ connectors and A/B radio output which have high isolation just like the 6×2 switches. This way it makes it easy to interface my station so I can access all antennas with up to four radios. I did some measurements and without doing any capacitance/inductance adjustments I got insertion loss better than 0.1dB on 1-30 MHz and the attenuation between the A/B radio ports was better than -80dB on 30 MHz. This will give me a HUGE attenuation between radio 1 and 3, radio 2 and 4 in my antenna switch system. When splitting power between two antennas the VSWR was around 1.2:1 as worst, while when power splitting between three antennas the VSWR was around 1.3:1 as worst.

I will do some real measurements when I have the real UN-UN transformer there to be used at my station, since I only had one ferrite (FT240-61) lying around now I just made a fast prototype while my boxes will be having two ferrite’s per box. However the measurements should not change much but I will post some graphs on here anyway.

Here are some pictures of the power split and the 6×2 while being tested. Here you can also see the coil modification done on the 6×2 cards. It is not mandatory but it does decrease the insertion loss a little bit.

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