Around this time of year I turn some of my radio attentions towards the medium wave band, though I have never started quite this early. Usually it's mid September or even October when I get around to constructing my flag antenna. I just fancied trying things a little earlier this year as we are in a new property and I wanted to know if the band was quiet here. Walking around the garden, listening to a portable radio, my Degen DE1103, showed that the band is very quiet indeed. Will a flag be equally as quiet though?
This season I was thinking about running two flag antennas. One for the North American continent and one for the far east. One corner of the garden seemed perfect for these flags and it was my plan to devise some system where I can have a movable flag. Two pairs of supports could be fixed along two fences which would allow me to lift the flag out of one set and into another. That was the plan.
Nervously, I began to construct the supports for the flag and fixed them to the fence. "Nervous"? Yes, very. It's because I have had so many problems with neighbours in the past that I have become really conscious of my hobby and everything about it when it comes to almost any aspect hobby that I begin to look over my shoulders to see who might be watching. Accounts of my many problems on this matter are documented elsewhere in this blog.
Back to the construction. As I fixed the supports for the North American flag to the fence I spotted something I had missed. A telephone wire, coming down from a telegraph pole outside the front of a neighbouring property and into the roof, was going to be right in the way of the North American flag. This flag would be ten feet high off the ground and would actually touch the cable, running parallel with it for a couple of metres. Would this telephone cable cause any interference? I placed my DE1103 near the wire and listened with disappointment as the radio gave out a horrible growl, right across the whole of medium wave. Bang goes the North American flag!
Undeterred, I proceeded with the construction of the far east flag, which would be about four or five metres away from the telephone cable. I had this up and running in no time and went to the shack to make the final connections. Switching on the Perseus revealed a superbly quiet medium wave band. Long wave was also fabulously electrically quiet. There was no need to insert my ferrite chokes as I was forced to at the previous address due to the excessive electrical noise I experienced there.
Time for a quick tune around the medium wave band. I adjusted the variable resistor to get a null on 1026 kHz, the frequency of BBC Radio Cambridgeshire. This transmitter is roughly on the back end of the flag's 'beam' and I managed to eliminate it completely, leaving what I presumed to be Tabriz, Iran, completely dominating the frequency. 1521 had a clear signal from CRI, Urumqi, China. This was actually producing a stronger signal than was my local station, BBC Radio Lincolnshire on 1368!
So far so good. Fingers crossed now that conditions pick up and give us all some good medium wave DX.
No comments:
Post a Comment