纯新手，端馈天线比较隐蔽，感觉搭建的可能性比较大，不会像GP之类的被投诉。想问下大家端馈天线效果如何？好用吗？和5米的GP天线比呢？欢迎大家贴出自己的端馈图片和通联成果。73

能用别的如正 V 就尽量别用端馈

@"BG2ELG"#p31357 正V比端馈强多少呢？

架设高度足够的端馈增益比GP好，但你需要能够理解怎么样消除不平衡天线带来的射频干扰（其实就是馈线套扼流环）。端馈可以斜拉，可以水平架设，也可以倒V架设。当然你需要一个VNA来根据不同的架设方式进行调整。至于通联效果，我用5瓦ft8差不多完成100 DXCC，最远乌拉圭巴西阿根廷啥的

我这个长线+天调也可以算端馈吧。效果还可以。 [upl-image-preview url=https://storage.hamcq.cn/2024-08-30/1724999142-324936-mmexport1724572088429.jpg]

@"BD7JIR"#p31436 野架啊，羡慕，不过你这个绳子怎么搞到树上去的？

@"BG7NOD"#p31461 矿泉水瓶子绑好，扔上去。线天线不占地方，40米-6米波段都能调谐，不用带天分，耳朵听底噪就能知道是否调谐了。爬山一个背包里还能放吃的、喝的。

@"BD7JIR"#p31436 印章键好评

@"BD7JIR"#p31436 我也是818，端馈天线，14兆驻波完美，携带很方便

What are your thoughts on end-fed antennas? Experienced users, please share your insights.

BG2EWI

BG7NOD You mean the standing wave amplitude is low, right?😋

BG7NOD

BG2EWI Low, that definitely means low. A low resonant frequency is just one condition for high efficiency, but a low resonant frequency doesn't necessarily mean high efficiency. However, a high resonant frequency definitely means low efficiency. A low resonant frequency only indicates that all the energy has been transferred, but whether the device receiving the energy can reasonably convert it into electromagnetic radiation depends on the device itself.

BI1LWR

It's relatively user-friendly for beginners, simple to set up, and a good starting point.

Later on, requirements for launch efficiency and other factors led to the use of complex, bulky antennas.

Now, when I go out, I use the large antenna I made myself. I put it in my 705 bag and, with a power bank, I can easily set it up anywhere. It's convenient, and whether or not it works depends on luck.

FT8, excellent range.

BG6HFD

End-fire antennas are essentially a trade-off.
Based on my own experience, the main issue with the end-to-end system is its generally low efficiency in transmitting signals.
The advantages are also clear: compared to other antennas, it is more discreet because it's simply a wire. Installing it on the rooftop gun emplacement for a long time doesn't easily raise suspicion, and installation and dismantling are also easy; furthermore, it's affordable – you can buy good quality wires for just a few hundred yuan, and the reception performance is also good.
It's stronger than my balcony fishing rod and various other models, but weaker than a pull-up bar. If compared to a 750V type, there would definitely be a difference. I feel it's better than the GP installed on the ground (probably about the same as installing it on the roof). This is the user experience in an urban fringe area.

BG8AMG

Advantages of end-fed antennas: Easy to install, less conspicuous, and operate across multiple bands. When installed at the appropriate height, they can still perform reasonably well.
Disadvantages of direct feed: Lower conversion efficiency for the Balun, resulting in higher losses. The high-frequency lobes are more fragmented, leading to dead spots in some directions. The relative noise level is slightly higher than that of DP, and also includes issues related to unbalanced antennas.

Due to the various obstacles and difficulties encountered when deploying antennas currently, the advantages of direct-to-home (DTH) systems can be effectively utilized. First, the issue of whether or not to implement DTH is resolved.
Actually, using a direct connection (end-to-end) is also cost-effective and can be implemented initially. You can then upgrade to a better setup later if the conditions are more favorable.

BI1RRE

The 20-meter end-fed antenna arrived yesterday. I tested its performance in the park this afternoon, and found that it needed to be positioned in a location where it wouldn't be obstructed. I tried several different positions, but ultimately settled on one where the top of the antenna was unobstructed. The 7, 14, 21, and 28 MHz bands have relatively low propagation, which is ideal for QRP operation. Using a QRP radio, I managed to make contact with three stations, including one local station, and two others within approximately 500 km. I was also able to hear some SSB transmissions on 14 and 21 MHz, although no one responded to my CQ calls. The 28 MHz band had too much noise for QRP operation. Using FT8, I managed to make contact with two stations on 14 MHz. While the 7 MHz band had a lot of activity, I was unable to make any contacts. FT8 requires a good ground connection, otherwise your phone's USB or computer USB may malfunction. Overall, setting up and storing the end-fed antenna takes longer than using a GP (ground-plane) antenna, but it offers the advantage of being able to operate on multiple bands without having to constantly adjust and add antennas. If possible, I would like to test it outside

BG4TRF

Comparison of efficiencies for MM0OPX End-Fed Half Wave Transformer

If you buy genuine products, three 240-43 magnetic rings with 88% efficiency are the best. The other two models are not available for purchase in China.
And to speak of the unknown magnetic ring I built myself... I disassembled several TB models, and even didn't add any capacitors.

BG7NOD

BG4TRF This is impressive! Have you tested any BH7JYR end-to-end devices that are sold on Taobao? I've heard they are quite good. Do you have any real-world testing results to share?

BG5GOO

While I don't recommend using a feed-line to connect to other antennas, I personally use one. Since I live on the 5th floor and have a tree about 5 meters away that is slightly tilted, the feed-line has saved my radio dreams. The main reason is that I generate too much interference myself, but it's still a good option even without ideal conditions. Currently, CW communication with all major continents is possible, and SSB communication in Asia and Europe is also relatively easy. If you play FT8, you should be able to connect with countries around the world.

BG7NOD

BG5GOO I was particularly struck by your statement: "The end-fed antenna saved my radio dreams." Of course, I would have liked to use a proper vertical or a better Yagi antenna, but the circumstances didn't allow for it. However, having an end-fed antenna really made all the difference. At least, I could receive several strong signals on 14 MHz. And in the evenings, I could pick up a lot of communications from Southeast Asia on 7 MHz. I was also able to receive a good number of CW signals.

BH4GQD

BG7NOD The JYR antenna is pretty good. I used it during the autumn harvest season and was able to receive SSB signals from Australia.

BH5UNT

A helpful tip: The impedance of the downlink antenna is around 2450Ω, so a 1:49 Un-Un transformer is needed to match the impedance (here, "Un-Un" refers to an unbalanced transformer, which uses a toroidal core and enameled wire winding to match the impedance without performing a balanced conversion). However, this also means that some energy is lost in the heating of the Un-Un transformer.
You can take a look at this open-source project: https://github.com/DG1JAN/UniBalun

BD3OLH

The feed-forward antenna itself cannot compare to a simple dipole under similar conditions.
However, it has several irreplaceable advantages: 1. Multi-band operation: A 40m long cable can perfectly cover 8 bands, and a 20m cable can perfectly cover 4 bands, without the need for an ATU (Automatic Transmitting Unit). 2. Easy installation: Only one support is needed, with minimal environmental requirements, allowing for various installations such as horizontal, inverted V, L, inverted L, and tilted configurations. The feed point is close to the ground, requiring only about 1 meter or even handheld operation. This makes it convenient for field installations and saves on feed lines. 3. No interference: I have not experienced any interference so far, and a 1:1 balun placed at a distance of 0.05 wavelengths from the feed point is sufficient.
However, it also has inherent limitations due to its design: 1. The base noise is larger than that of a dipole antenna. 2. Using a high-ratio transformer (49:1 or 64:1) results in slightly lower efficiency, but can still achieve over 80%. With carefully designed end-fed designs, efficiency can also reach over 90%. If used with QRP, it is suitable for CW and digital modes. Of course, it can occasionally be used for SSB as well, but if the power is 100W, the losses on this antenna are negligible, and a dipole antenna can still connect to an EFHW antenna without any significant difference. 3. The radiation pattern is complex and difficult to predict. However, anyone who considers the radiation pattern is essentially an expert, and the use of EFHW is rare in such cases.
If you want to use the EFHW as your main antenna, I recommend making it yourself. The main cost will be in the magnetic loop. During the process of building the antenna, you will learn a lot and can achieve better efficiency. I have purchased and built one myself, so I have experience.
Another piece of advice is: cheap goods are not necessarily good quality. Those who buy tend to have a better understanding of quality than those who sell, because sellers always aim for profit, and that means they need to ensure the product's quality.
When I was able to make contact on 14 MHz this year, using a 20-meter long, 10-meter high EFHW antenna that I built myself, it performed surprisingly well compared to a 6-meter tall four-band Yagi antenna. This demonstrates that antennas are important, but height is even more crucial. This is just one example and doesn't represent any particular trend or conclusion.

BG7NOD

BD3OLH This is very well written, thank you for sharing your valuable experience. 👍👍

BH5UNT

[未知用户] These two models can be purchased through the Liuchang store (source from Mouser). The import tax is 1%, and domestic shipping via SF Express costs around 8 yuan. If you buy two, the cost per unit will be approximately 10 yuan. Although there are also factories in Shenzhen that offer inquiry and ordering on Taobao (but their shipping costs are much higher than Liuchang's).
(Not an advertisement)

Hangying

Learned, learning...

BH7JUO

My impressions of end-to-end (E2E):
In the past few years, whenever we held CW competitions, we would set up a skimmer decoding server at my friend's house. His apartment was on the top floor of a building on the 32nd level, and he used a 20-meter whip antenna to feed the signal to a receiver operating in the 15-meter band. I used a 3-element Yagi antenna about 10 kilometers away, also on the top floor of a building on the 11th level, and could clearly hear the signals. The matching was approximately equal for everyone.
At the second location, a friend brought another 20-meter end-fed antenna and hung it on a tree. When the FT450 was turned on, all frequency bands had S9 noise, with even higher noise in the lower frequencies. I couldn't figure out what was causing it. Then, suddenly, I remembered that there was a medium wave transmitter about 2 kilometers away. This thing transmits during the day... After switching to a harmonic-tuned GP antenna, the noise level dropped below S2, and I was able to make contact.

BG7NOD

BH7JUO This was a very helpful and informative sharing experience. Thank you.

BG6HVC

Setting up a GP radio is very convenient. However, you need to adjust it when switching frequency bands. After receiving the antenna and other components, try it out and see how it performs. The biggest factor with shortwave radios is the environment; you have to rely on luck.

BG6HVC

[未知用户] That's great! I haven't been out to sea yet.

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