Monday, July 21, 2014

July 20, 2014 Six Meter Opening


This past weekend (July 19-20, 2014)was a flurry of activity in a short period of time. Company in the house had kept time before the radios to a minimum, but a short period Sunday afternoon more than made up for it.

A friend  had antenna trouble earlier in the week and I managed to take time off from visiting to run by his house and help him trouble shoot the problem. During the course of the visit, we talked about six meters and talked about a quick way to get an antenna up for at least listening on the band. The idea of a wire antenna was already on the table because of my somewhat success in using my 90 foot sloper as an interim antenna on six and the discussion turned in that direction.

We looked at how it is common practice to use a forty meter antenna on fifteen meters. The third harmonic relationship of those two bands means that a half wave antenna on forty becomes a 3/2 wave antenna on fifteen, matching fifty ohms rather closely on both bands. In fact, any half number of half waves will do the same.

Looking at his space available, it was determined that there was room for a 7/2 waves antenna for six meters, it turning out to be about 63 feet long. Interestingly enough, this also would make the antenna useful in the forty meter 'phone band! It was decided he would try putting it up in an inverted Vee configuration as is common for HF operation.

Sunday afternoon, he told me that he had the antenna up and it matched up pretty well without a tuner on six.. As I returned from a road trip taking our visitors back, I got a text from him, first saying he had worked a South Carolina station ( from his  Central Texas QTH) on six with good signals and that there appeared to be a contest on. Just a short time later he had worked 12 stations in 7 states. The top of the wire was probably about 30 feet up.

I checked the contest calendar as I settled back in and noticed that it was the weekend for the CQ World Wide VHF Contest...but it was ending just as I sat down. Since my friend had mentioned the band was open, I decided to tune through the band anyway, if nothing else to see if a few beacons were coming through. I also figured that if the band was really open, a few operators would continue to try to work some VHF DX even if the contest period was over.

Turned out I was right on both counts. Just tuning up from the bottom of the band up to the area where I often hear beacons ( 50060-50080) I quickly ran into an extremely strong signal from WZ8D, on 50067.25 indicated on the R-75 Signal was S-9, sometimes hitting 10 DB over S-9! Yep, there was a band opening! This was at 2106 GMT, just six minutes past the end of the contest.

The receiver was in the wide bandwidth, and I could hear another somewhat weaker signal adjacent, so switching in the 250 Hz filters, it was easy to separate out WA3TTS/B, another beacon on 50068.5 indicated, not quite as strong, but very respectable.

Over the next half hour or so, the following appeared in the reception log ( all times GMT)

2108 W8IF/B 50079.25 579 CW Beacon
2112 WD8CW 50098.2 559 CW calling CQ
2113 K8LEE 50077.9 589 CW Calling CQDX
2114 N5DG 50104.5 549 CW Calling CQDX
(very weak at times, deep fading and a flutter, almost buzz modulated-backscatter?)
2115 K4RX 50103.5 559 CW Calling CQDX
2121 AC4TO 50107 539 CW working another station
2123 AB5EB 50106.25 559 CW Calling CQ DX(fluttery)
2124 KB9AX 50106.5 589 CW Signing with another station
2129 KD8NYL 50130.2 57 SSB In QSO
2130 K4RX 50103.2 589 CW Calling CQDX
2133 WA9IOC 50094 579
2134 W9CPV 50093.25 569 CW
2135 WR9L/B 50074.4 579C CW Beacon
2136 W0FY 50074.4 579 CW Beacon
2137 K0KP 50073.4 589 CW Beacon
2141 K8TB 50065.3 549 CW Beacon
2142 W8EH 50060.6 579 CW Beacon
2144 W0ZF 50128.1 58 SSB
2147 KG9Z 50096.1 579 CW CQ

It might be worth watching the VHF publications and other blogs, because I heard some of the stations apparently working Europeans, though they were not audible to me. I heard at least two stations appearing to exchange signal reports with an ON station and one with an Italian.

It was also interesting to note that relatively nearby stations ( near in the overall scheme of things, not actually local in the Waco area) were obviously multi path back scatter signals with echo, flutter and almost a sound of being modulated by a buzz.
 
I continue to be intrigued about the idea of using long wire antennas for VHF. There is gain to be had and the multiplicity of lobes makes reception from various directions possible.  It can also allow operation or reception quickly without complicated antenna construction.  Not to say that it would equal stacked multi element yagis, but the inability to get those up should not be a reason not to get on the air or to listen. Feedline does become a consideration, however, as losses at these frequencies are higher and at least a fair match is necessary to avoid even greater losses. open wire line might be a consideration and experimentation is on tap for that here.

I would be interested in hearing from anyone else who noted this opening or others, particularly anyone in Europe who noted it or even heard some US stations.

This opening was particularly interesting because this week has been marked by a very quiet sun, few if any sunspots. All during the week, the upper bands have been poor or totally silent here, thought 20 meters has continued to surprise with openings to Russia and Asia in the 0200-0300 time period.

I hope to have more time to explore what is going on with the bands this week. This past week was filled with visiting grandbabies, and after all, this is “ just a hobby.”



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