The items contained in this column come from recent discussions on the NRC listserv. I want to again emphasize that the contents of the answers provided below are a composite of various replies also presented on the listserv. Some are my own responses, but many are not.
Q - I have a CCrane Radio and a random wire antenna strung up under the eave off the house. Any further outdoor antenna is out of the question because of local restrictions:
1 Am I getting the most out of my rig that is to be expected?
2. What kind of efficient "low profile" antenna could I get without being sent to Leavenworth by the Home Owner's Association?
3. Is there anything I should be doing to maximize the equipment I already have?
4. Should I change or modify the antenna I presently have?
A - I'm not very familiar with the CCrane firsthand - only through others, but I believe I can provide some assistance regardless:
1. You are probably getting as much from the radio as you can, given the antenna. You could probably improve it somewhat with a better antenna, but you do have limitations in that area. That said, the CCrane is a ‘consumer radio’ meaning that it is not designed to have the type of performance of a radio designed for hobby use. You didn't mention it, but depending on your budget, you could upgrade the receiver also.
2. Your best bet would likely an indoor antenna. Radio Shack makes a passive loop and an amplified loop. KIWA also makes a pocket loop, however those are temporarily unavailable due to the company relocating. None of these is particularly costly.
3. I think the answer to this is "see prior answer". I would wonder if you've tried both with and without the ground to see what difference it makes. You could also try tuning/matching the antenna to the radio using an inductance/capacitance circuit. Additional details on that can be found in the NRC Antenna Reference Manual #1, available through NRC Publications, depending on your interest in constructing something.
4. Yes. See the second answer. Also and again depending on your interest in construction projects, you could build a loop antenna. An antenna of this type may be more unsightly and will certainly take up more space, but that's the price for performance on a budget. There are excellent commercial indoor antennas available, but the cost is measured in the hundreds of dollars. Check out NRC Publications for specific projects.
Q - I just extended my backyard longwire that now probably meanders about 300-350 ft. or so around the back of my property. I added on to it by tightly intertwining the end of the original longwire with the new length of incremental wire and then secured it all very nicely with weatherproof electrical tape. I couldn't solder the connection because I was about 200 ft. from the nearest electrical outlet! Because I didn't solder the connection do you think it would somehow negate the additional length I've added because it's not "connected' properly??
A - I'm afraid that the best answer I can give you is 'maybe'. It could depend on whether or not you did a really tight job of intertwining and then taping. BTW, you can do a great solder job with one of those small portable propane torches set at low flame, or possibly even one of those grill lighters that produce a flame rather than having just a heating element. Also, in a situation like this, you could try encasing the joint in a small plastic pill bottle or case, and sealing it with putty or caulk, either of which will probably last longer than the tape.
If the wire is suspended at all, you’ll also need to be concerned with possible breakage through strain. Attaching a hanging wire to some fixed object ( a fence post perhaps or a tree trunk ) in such a way as to permit the solder join to hang between two such connections relatively closely spaced can help, as can other improvised means of mechanical strain relief.
In general, with wire antennas, you often end up just experimenting and seeing what works and what doesn't. Where I am, I haven't yet found a longwire setup that doesn't present too much noise. I also can't get a single straight line run of more than 100' or so, and I can't do one of the 'noise-reduced' wires because I can't get the lead-in under ground to come back to the house thanks to a patio and a sidewalk.
Q - I'm running Geoclock on the shack computer, so sunrise/sunset mapping is no problem. What is the significance of stations that are required to reduce power at local sunset?
A - Just having Geoclock - as I do also - doesn't give you the 'approved, official' FCC Local sunset time for the station even if you have the precise coordinates. The FCC AM Query shows those.
The significance is that, as sunset approaches, the ionosphere starts to change, and distant propagation is more likely. Thus if you listen just prior to their local sunset time, you have the best chance of hearing them because they'll still be on day power, but subject to propagation characteristics more like night.
As an overly to that, this effect is magnified in the fall months during the last two weeks of the month, and in the early months of the year, during the first two weeks because the FCC LSS times are based on a mid-month average. Thus, the idea is to maximize the degree of darkness at the station ( and consequently, along the signal path from them to you ) while they're on day power and pattern.
The exception to this would be those cases where the power difference is small or none, but the nighttime pattern actually is more favorable to you.
A (somewhat) related note: any station to the west that has a favorable nighttime signal in your direction (significant night power and no deep null aimed at you) is a potential sunrise target. The period around your local sunrise often produces a window that brings up the relative strength of stations to the west of you. This is because absorption in the D layer increases rapidly when solar radiation hits it, and it's being illuminated to the east of you, but not to the west, during the sunrise transition. Sort of like an RF-absorbing curtain being drawn across the sky from east to west. So, the eastern stations that were there all night tend to get knocked back, allowing the westerners to emerge from underneath. On rare occasions, the window will persist well after sunrise, long enough for some of the western stations to start going to day power/pattern.
Here, as with sunset, the time of month can also be critical, as the more darkness on the path, the better. As sunrise times get later in the fall, the end of the month is preferable. In the spring, the beginning of the month is better.
It also pays to realize that the shortest day of the year ( usually December 21 ) is not the day when the sunrise is latest and the sunset earliest. Those two conditions do not even occur on the same day. The earliest sunset time at mid-latitudes is usually between Dec 5 and 10, while the latest sunrise times are right around December 30. Since December 21 is between those two, it is usually the shortest day of the year. This means that December can be viewed as a ‘fall’ month in terms of sunrise DX, but should be considered on the same plane as January for sunset DX.
Please remember to keep sending me your questions or your suggestions for future topic-oriented columns to me either via the NRCDXAS listserv, by off-line email or by regular mail! I’d like to acknowledge , Barry McLarnon, who provided material for answers in this column.