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Receive Antennas (below 30MHz) - For all topics related to receive antennas used on HF, MW, LW, etc. For transmit antennas use the Amateur Radio Antennas forum.

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Old 09-04-2017, 2:13 PM
   
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Default Worse reception with random longwire

I have an ETON E5 receiver that I got to listen to shortwave.

Put up about a 40' longwire running east to west, was getting some reception but nothing to write home about, so I decided to add an additional 100' running north to south, now I have little to no reception, on any band. So, me being new to SWL, I looked and looked to see how to ground the antenna, thinking that may help, plus give me a point for lightning strikes to go instead of inside my shack, I used 14g wire, wrapped it around the feedline coming into the shack and mounted to a grounding rod 6' in the ground with a copper fitting, no change.

I'm in East Central Ohio.

What the heck am I doing wrong, I'm having no luck here, and suggestions would be helpful
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Old 09-07-2017, 1:28 PM
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I have no experience with the Eton E5, but would normally expect that an external wire antenna would work better then the built in whip antenna for the HF bands. (For the FM broadcast band the whip will probably work better).

Try tuning to the WWV frequencies 5, 10 or 15 MHz. That should give you a steady signal for comparison. Depending on the time of day you will find that the frequency that works best may vary. Once you have WWV tuned in try alternating between the whip antenna and your wire antenna.

Not to be a jerk, but have your verified that the wire is making good electrical contact through whatever adapter or plug you use with the radio?

In the evening after dark there should be plenty of strong ham signals on 40 meter sideband between 7.15 and 7.3 MHz.

Good luck.
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Old 09-07-2017, 1:49 PM
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Keep in mind that we just had a major X9.3 flare hit us with not one, but 2 CMEs. Conditions right now are likely to be terrible for a few days until the effects of the storm (at one point, there was a major G3 class HF blackout) wear off. Bottom line, it's a little tough to make any judgments about antennas while we're still reeling from solar storms.

And I would stress that a single ground rod is NOT a particularly good ground, RF wise. You might even be better off with no ground at all. There's another thread discussing this topic in detail.

How are you connecting the antenna to the radio - hopefully through the mini antenna jack? Never connect to the whip directly, as any static charges going through the wire into the whip will very likely render the radio as deaf as a rock.

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Old 09-07-2017, 1:52 PM
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This thread discusses a little box you can easily build to drain off static charges, but in any case, during a T-Storm, disconnect the power and antenna and get the antenna as far from the house as possible. There are no absolutes when discussing lightning protection; at some point you could get hit.

https://forums.radioreference.com/re...r-project.html

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Old 09-13-2017, 12:13 AM
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Ditto on the ground probably not being much help. Grounds never helped me any.

Being that your Eton is a SW digital portable, 100 ft of wire should be plenty to bring in signals (PS Always be careful with an external outside wire antenna when using it with a digital SW portable. Not just lightning, but during winter or very dry air conditions static discharges can zap a radios RF amp transistor(s).

But propagation for SW has been mediocre over the past year, and we have had auroral / poor solar conditions over the past few days. Yesterday evening I heard four SW stations -- count 'em, four. Two Radio Havana outlets in Spanish on the 49 meter band, a very weak CRI China (I'm in the NW US), and a dead carrier on 5025 kHz Radio Rebelde. That was it.
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Old 09-13-2017, 3:12 PM
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How are you connecting the antenna to the radio - hopefully into the proper SW external antenna socket. If you are just clipping the antenna to the whip antenna you could be overloading or detuning the input stages of the radio or worse still - blowing the FET input amplifier.
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Old 09-13-2017, 7:44 PM
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According to the manual for your radio, the external antenna socket is intended to accept a 50 to 75 ohm input. For best performance with a random wire antenna, you should use a 9:1 matching device.

Otherwise, HF propagation has been terrible lately.
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Old 09-13-2017, 8:52 PM
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I've been getting pretty much the normal decent reception on shortwave for the last 3 days. And +1 on WA8ZTZ's post especially if you're treating that "wire" as an "endfed".
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Old 09-14-2017, 10:32 AM
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Another option would be to make a 'zip cord dipole' out of speaker wire, by separating the sides and pulling them, making a sort of dipole. I did that with my DX-440 a long time ago and it worked rather well. Better than the whip. I didn't use it outside, of course. But you just solder each side to one of the 1/8" plug terminals and you have a reasonably balanced antenna with no balun (or ground, for that matter) necessary.
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Old 09-15-2017, 3:08 AM
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Zip Cord Dipole below reminded me of a simple HF antenna described by Bob Grove in his article "Closing Thoughts" in the December 2013 Final Edition of Monitoring Times. I have used this setup with much success when away from home.
I'll quote it here as not sure how to post attachments.

"Over the years, I’ve answered more questions about antennas than any other subject. There are no mysteries about antenna design, but there is misinformation. In general terms, a good transmitting antenna is a good receiving antenna, but the reverse isn’t necessarily true.
For shortwave listening, sensitive modern receivers will pick up signals worldwide with only 20-30 feet of wire, vertical or horizontal, any gauge, insulated or uninsulated, and copper or aluminum. Just make sure it’s in the clear of large obstructions and at least 15-20 feet above the ground if it’s horizontal. Verticals work fine mounted at ground level so long as there are no nearby obstructions. Erect it as far from your residence as practical to avoid electrical noise sources.
Do you want the best and cheapest short- wave receiving antenna you’ll ever need? Take a 24 foot length of paired “zip cord” (speaker wire, household electrical cord, etc.) and remove 5 additional feet from one of the conductors making it 19 feet in length.
Cut back the outer jacket and shielding on your coax about an inch, and cut about a half inch of the insulation away from the center conductor and solder it to the unseparated end of the two wires. No ground is needed.
Tie about a foot of twine, rope or string to the end of the single wire, and tie a knot around a rock on the other end of the rope. Throw the rock as high as you can (at least 24 feet!) over a tree branch. That’s it. It’s best to use a tree at some distance from the house to reduce electrical noise interference, and of course enough coax to reach the radio. The coax can lie on the ground or even be buried to keep the squirrels from eating it!"
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Old 09-15-2017, 11:31 AM
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FWIW, my zip cord dipole was around 15-20 ft., end to end. An antenna like that doesn't have to be cut for the entire SW band, even 15-20 ft will work well (5-7 meters for metric people). I just soldered the ends of the zip cord to an RCA plug (the DX440 has an RCA input jack). Stripped apart around 15-20 ft. of it, and left 5-6 to go from the 'T' to the radio (probably around 30 ft cut from a spool, in total, to work with).

Like I said, the still-'zipped'/unseparated portion of the wire was maybe 5-6 feet, enough to get it away from the radio and out onto the floor, or up onto the wall. Not being coax, I suppose it's not a 'true' dipole, but it worked well. I still have it stashed away somewhere.
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