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A Rough Radio Weekend

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During the past week I swapped out my ~105′ ladderline-fed doublet for an Alpha Delta DX-LB Plus. I finally got the LB up in the air on Friday, with the help of some family. The LMR-400 I’m using to feed it is heavy, and the LB Plus itself is heavy, so it was causing the mast to bend pretty good without guy wires above 25′. As a stopgap measure I tied a piece a rope to the top section and secured it down in a way that would bring the mast back to vertical.

The LMR-400 was purchased from a place who had premade 50′ sections with N-connectors used for wireless backhauls. Not only do I not need LMR-400 on HF, but I also don’t need N-connectors on HF. This just causes me to have to use adapters to connect it to antennas and radios. The current LMR-400 likely has water breach. The N-connector on one end can easily be twisted, and there is intermittent connection of the ground. I ordered some RG-213/U with PL-259s which should be here this week.

I didn’t get an opportunity to even attempt to tune the 10/20/160 wires. The antenna doesn’t resonate inside the band edges for any ham band. Although, my LDG tuner will very quickly tune up on 10m through 20m. I was also able to tune up on 160 around 1820 khz. I can tune up on 40m as well, but there is RF floating around in the shack. I’m not sure if it is due to the close proximity of the antenna to the shack, the bad shield connection on the coax, or a combination thereof. So I can’t run 100w on 40m right now. I’ll worry about that once I have the new coax in place. I can tune on 80m, but only in the SSB portion. Not good — I prefer CW.

It rained most of the weekend. Fortunately there was no lightning, but there was no way for me to know whether there would be lightning. T-storms were forecast. So it was always in the back of my mind that I may have to quit any contest I was operating in this weekend. The noise on 40/80 was rough.

I attempted to operate in the WAE CW contest this weekend. I didn’t do as good as last year, but I didn’t put the time in either. I missed some opportunities because I couldn’t operate on 40m without the RF taking out my keying interface every time. So it was a 10-20m contest for me. Unfortunately, there was no Europe to be heard on 10m. On 15m I felt the conditions were mediocre at best. I did make some EU contacts, but there is no way in hell I would consider it to be good propogation on 15m this weekend. Others in Ohio who worked this contest wouldn’t agree, but they are also running high [and often directional] antennas and high power. 20m was good though, and that is where I made most of my contacts.

I worked a few MDC stations for that QSO party, but try as I may I just couldn’t find many on the air. I worked what I heard though. The MDC QSO party is like the WVQP — a handful of in-state stations who have all the fun working the casual people who run across them, but in my opinion there aren’t enough in-state MDC stations to make the contest fun for those out of state. Contrast that with the FLQP, GAQP, TNQP, OHQP, PAQP, CQP, and the 7-land QPS, where there is plenty of fun to be had for both in-state and out-of-state stations.

On the bright side, I was offered some help by my niece’s husband to relocate the current antenna support to another part of the yard farther away from the house. We’ll do that in the next month or two. We’ll dig a hole and cement a pipe into the ground and then mount the 50′ Max Gain Systems mast to it. I’ll put the DX-LB Plus on top, and perhaps I’ll stick a single-band wire below it. We’ll get some solid end supports in the ground as tall as I can get them… above 10 feet at least. Hopefully I can figure out how to do this in a way that allows me to use pulleys on it to raise and lower the wire(s) rather than having to retract the mast for maintenancce or during inclement weather. The 50′ mast has 8′ sections, while my current mast has 6′ sections. So, retracted it will be more difficult to work on things using the 50′ mast. And I definitely need to get that DX-LB Plus tuned for resonance inside the band edges of as many bands as I can.

Written by Mike

August 15th, 2011 at 10:08 am

Alpha Delta DX-LB Plus – Part 1 : Arrival


Some preliminary babble…

I had mentioned elsewhere on the site that I’d like to have a 160m antenna. I had given consideration to an inverted-L or a Marconi T, but I came to the conclusion that not only would I not be able to create a vertical section of reasonable height but I also would have difficulty extending the horizontal portion as far as it needs to be and have a proper anchor point for it. And if I could manage to secure the horizontal end, it would be facing a direction that I don’t particularly care about. [It is my understanding that there is some bit of directivity towards the direction that the horizontal portion runs from the vertical portion]

I’d lie if I said I wasn’t interested in 160m DX or working working all states on 160m, but now is not the time to do that. I do, however, want to be able to make my presence known on 160m during the ARRL 160m contest and some of the QSO parties that have 160m as an operational band.

Since I have experience with the 42′ Alpha Delta DX-EE dipole, and since I think it is well constructed and has performed quite well for me, I figured I’d throw down the nearly $200 for the DX-LB Plus dipole. This is shortened 160m/80m (shortened) that will also handle 40/15m, with additional parallel wires for 20m and 10m operation. My DX-EE tunes 30/17/12 and I’m hoping I’ll be able to get a match on these same bands with the DX-LB Plus without too much loss.

The dipole arrived and is still packed up. When I removed it from the box I was surprised at how heavy it was. It’s well constructed. The wire is heavy and of course the addition of the inductors makes it even heavier. I suspect that if I don’t manage to get the dipole erected in a way that the two ends are 180 degrees from one another, it’ll probably cause the top section of my Max Gain Systems mast to bow.

I really can’t stand wiring up the parallel wires. And I really don’t want to think about tuning and pruning it so that it’s resonant inside of the CW sweet spots of 160m and 80m, especially since the 3:1 bandwidth is very narrow.

I’m still debating whether I should put this up as a flattop oriented E/W (broadside N/S) or as an inverted V. Either way the center will be @40 feet. If it is an almost flattop, the ends will be at about 30′. If it is an inverted V, it’ll really be rough to have the ends very far off the ground — probably no more than 10 feet, although I’ll strive for 13-14 feet.

As constructed and delivered, it is intended to be fed with coax. However, I do have the option of feeding it with 450-ohm ladderline (~45 feet) into a DX Engineering 1:1 current balun, through an 8′ piece of RG-213 into the radio. If I have too much trouble tuning the antenna, I may opt for feeding it with ladderline as it will make it easier to tune. Of course, feeding it with a random length of ladderline into a balun is not quite the same as feeding it with only ladderline and tuning it with a tuner that accepts balance feedline.

Already I’m losing ambition, just like I did with the DX-EE. It took me three weeks before I ended up putting the DX-EE together since I had to string the additional parallel wires through their standoffs and secure htem at appropriate points. In this case it’s going to be even more difficult since I’ll be dealing with trying to get it to be resonant in a specific small portion of 160m and 80m.

I’ll write more as things progress

Written by Mike

October 14th, 2010 at 3:52 pm

Posted in Antennas

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