打算手搓八木天线要用什么材料

木龙骨，铁丝，馈线，锡焊，天分，钳子，尼龙扎带

提醒几个地方：注意天线接口有M头、N头、TNC头、BNC头、SMA头五大类，每种头还分公母，买馈线时务必注意接头型号（不建议买裸线自己接），可能需要买转接头。以及注意天线本身阻抗是50Ω还是75Ω还是300Ω的，阻抗不匹配后面还得用巴伦。龙骨可以用PVC管代替，另外有种东西叫做龙骨卡口/骑马卡。铁丝可以用不剥皮的铜质电线代替（粗一些据说性能比较好），也有人用钢卷尺代替（小心割手）。不建议在PVC上打孔穿线（打不准，天线不同面会影响收发效率）。如果不需要手持，可以考虑弄一个相机三脚架，然后买gopro的自行车支架（1/4螺丝），以及一个1/4双母牙螺丝，就能转接刀三脚架快装板上了。天线分析仪一般指网络分析仪（VNA)，现在比较流行的高性价比设备是开源的NanoVNA，但这里特别提醒一下，NanoVNA除了edy555原始设计，有很多衍生版本（如NanoVNA-H，冥鸿科技的NanoVNA-F，以及NanoVNA V2 (S-A-A-2，OwOComm或称HCXQS/NanoRFE，后续版本有“V2 PLUS4”等）），甚至固件不互相兼容。个人建议购买NanoVNA-H的2.8寸版本（大约230元）或者4寸版本（大约400元）。购买渠道一定要仔细比对甄选（此处不推荐购买渠道），避免买到元件偷工减料、早期抄板缺陷的山寨产品。天分/网分和频谱测试仪（如TinySA）的区别：天分用于测试天线性能，谐波测试仪用于测试射频设备发生的信号性能（如谐波及带外发射是否符合国家规定）。如果你不是DIY电台本身并要去验机，而只是做天线，只需要买网分。根据SWR表现，八木天线可能需要做gamma匹配或发卡匹配（beta匹配的一种）之类，大概就是加感/容调电抗。

看你要做啥样的，单u，单v，uv。应该不是短波吧，短波的八木我没发言权，我说一下uv的本人是UV卫星FM玩家，上星的八木都是自己做的 - 做一个能用的八木来说，最贵的也就是馈线了，十来块钱，其他材料能找到废弃的物品都行，例如主梁可以是个木棍，振子可以是铜芯线/卷尺。个人用做过一个花了20多块 - 如果是做一个能用且好看的，那主梁，振子，连接件上需要花一点钱。个人做过一个花了60左右，包括材料工具还有的剩，单天线上的材料只有30多块 - 从做天线享受乐趣方面，我的建议是如果没做过可以做单u的练练手，因为u的振子短，做起来方便，馈线可以多买两条或者一条重复用，如果要节省开支直接做便宜的，便宜的随便做不心疼。再做花费贵点的 - 如果是做来长期稳定使用，那一步到位做一个uv双段的，个人推荐用这个图纸： [点击跳转](https://www.qsl.net/py4zbz/antenas/ms.htm)，其实做个好点的不算工具也就三四十，其他的就是人工成本和技术成本，用pvc+联轴器方案的难点有两个，一是如何用有限的条件把孔打在一条线上，可以在关系外套上固定白纸，再将纸取下，对折后两边画点，再套回去。二是弯折莫克森(大框)部分成品： [upl-image-preview url=https://storage.hamcq.cn/2024-07-27/1722065515-276884-screenshot-2024-07-27-15-31-23-74-99c04817c0de5652397fc8b56c3b3817.jpg] ----- 馈电点连接细节解析(随手画的，凑合看) [upl-image-preview url=https://storage.hamcq.cn/2024-07-27/1722066020-757360-img-20240727-153930.jpg] ----- 耗材 [upl-image-preview url=https://storage.hamcq.cn/2024-07-27/1722065235-173427-screenshot-2024-07-27-15-26-28-28-ae1f93045b87aacac90efbb155289789.jpg] 希望对你有帮助 BD8CWG

@"yzyyz"#p25022 另外如果有天分更好，没天分按照图纸来做应该是没有问题的，即使在制作过程中不小心拿错了振子，让谐振点不在预期目标，也能用，(我不会告诉你我就是装错了振子让谐振点在U高还用了好长一段时间，我甚至用天分测了，在u高。我百思不得解，按图制作的，该调整都调整了，怎么没啥变化😂😂，就这样用着也一样打卫星，别人听我信号也是很清晰) 其实uv段的不要太刻意执着于成品驻波，差不多就行

天线主梁可以使用PPR管，管材外部的色线可以用来辅助定位，手法准的话用手电钻打孔就行，不过还是建议用台钻打孔，保证所有振子都在同一水平线上

手绘好评～另外看示意图，馈线是屏蔽层和内芯分别连接了两个1/4振子，是平衡天线，馈线应该是不平衡的。这样连接需要加平衡器吗

你需要一把精确的尺子。

@"Felix"#p25148 这个比较著名的yagi-moxon天线的设计者是LY3LP，根据4I1AWN的衍生修改版（主要是微调了moxon部分的宽度，还有详细描述了用料，优化了握把部分手感，并且单元穿孔方法有所差异），他把馈线绕了四圈，个人认为这相当于扼流balun。 4I1AWN的图纸如下（原本有一个更清晰的，但托管在wordpress上的原博客图片挂了，英文勉强看得清） [upl-image-preview url=https://storage.hamcq.cn/2024-09-11/1726039265-12720-4i1awnly3lpuvyagi-moxon.jpg]

@"yzyyz"#p25022 您图里的这一行看不大懂： **“25 20PVC水管，管帽，25-20直通”** ，是说水管的堵头吗？另外POM管参数为什么是**“3mm”**，是指厚度，还是输入错误？另，看您发的图，好像主梁是两段连接起来？望解答，谢谢~

Hand-made Yagi antenna

BD6ISM

What materials should I use to build a Yagi antenna myself?

BD8ENX

BD6ISM I'll move a chair over to read the responses from these experts.

BI9BRP

Wooden frame, iron wire, feeder cable, tin solder, grounding wire, pliers, nylon zip ties

BH5UNT

Please note the following locations:
Please note that there are five main types of antenna connectors: M, N, TNC, BNC, and SMA. Each type also comes in male and female versions. When purchasing coaxial cables, be sure to pay attention to the connector specifications (it is not recommended to connect bare wires yourself). You may need to purchase adapters. Also, please note that the impedance of the antenna itself is either 50Ω, 75Ω, or 300Ω. If the impedance does not match, you will need to use a balun.

The boom pole can be replaced with PVC pipe. There is also something called a "boom pole slot/horse collar". The wire can be replaced with bare copper wire (thicker ones are said to have better performance), and some people use steel measuring tapes as well (be careful not to cut yourself). It is not recommended to drill holes in the PVC to pass the wire through (it's inaccurate, and different sides of the antenna will affect reception and transmission efficiency).

If you don't need a handheld, consider getting a camera tripod and then purchasing a GoPro bike mount (with a 1/4 inch screw) and a 1/4 inch dual-threaded screw. This will allow you to easily attach the knife tripod mounting plate.

A network analyzer is generally referred to as a vector signal analyzer.（VNA)Currently, the NanoVNA is a popular and cost-effective device. However, I would like to specifically mention that, in addition to the original NanoVNA design by edy555, there are many derivative versions (such as NanoVNA-H, NanoVNA-F from Minghong Technology, and NanoVNA V2 (S-A-A-2, OwOComm or HCXQS/NanoRFE), and subsequent versions like "V2 PLUS4"), and even the firmware is not compatible with each other.

My personal recommendation is to purchase the 2.8-inch version of the NanoVNA-H (approximately ¥230) or the 4-inch version (approximately ¥400). When purchasing, be sure to carefully compare and select from reputable sources (I do not recommend purchasing from甄选), to avoid buying counterfeit products that are made with inferior materials or have defects due to early production copies.

Differences between a spectrum analyzer (like TinySA) and a harmonic test instrument: A spectrum analyzer is used to test antenna performance, while a harmonic test instrument is used to test the signal performance of RF devices (such as whether harmonics and out-of-band emissions comply with national regulations). If you are not building your own radio from scratch and simply need to test an existing antenna, then only a spectrum analyzer is needed.

Based on the SWR performance, the Yagi antenna may require gamma matching or beta matching (a type of beta matching), which essentially involves adding a variable capacitor.

yzyyz

Depending on what you want to do, choose single U, single V, or UV.
It shouldn't be shortwave, I don't have any experience with Yagi antennas on shortwave. I can talk about UV.
I am a UV satellite FM enthusiast, and all of my Yagi antennas that I deploy are self-made.

To build a functional Yagi antenna, the most expensive component is typically the feedline, which costs around RMB 10. Other materials can be sourced from recycled items, such as the main support beam being a wooden stick and the resonant element being a copper-core wire or measuring tape. A personal project cost around RMB 20.
If the goal is to create something that functions well and looks good, then the main beam, resonator, and connecting components will require some investment. I personally built one for around 60 yuan, including materials, tools, and leftover items. The materials for a single antenna cost about 30 yuan.
Regarding the enjoyment of building antennas, my suggestion is that if you are new to this, start with a simple "u" antenna. Because the "u" antenna has a short length, it's easy to build. You can buy multiple coax cables or use one cable twice. If you want to save money, choose an inexpensive option and don't worry about it.
If you plan to use it for long-term, stable operation, I recommend purchasing a UV dual-stage unit directly. Here's the diagram I recommend using: Click to navigateActually, a good solution doesn't require specialized tools; it typically involves around $30-$40. The remaining costs are primarily labor and technical expertise. There are two main challenges when using the PVC + coupling system: 1. How to create holes in a straight line with limited resources. This can be achieved by attaching paper to the outer surface, removing the paper, folding it in half, marking both sides, and then re-inserting it. 2. Bending the Mooren (large frame) part.

Finished product:

Detailed analysis of the connection details at the power input point (a rough sketch for reference).

Consumables

I hope this is helpful.
BD8CWG

yzyyz

yzyyz Alternatively, if it's possible to get the best results, following the diagram should work fine. Even if you accidentally use the wrong oscillator during construction and the resonant point is not where you intended, it can still be used. (I won't tell you that I once deliberately used the wrong oscillator to place the resonant point at U high, and it worked for a long time. I even measured it with a frequency counter at U high. I couldn't figure out why, even though I adjusted everything according to the diagram, there was no change.)😂😂(I was able to use it just as effectively as others, and my signal was clear for others to receive.)
In reality, you don't need to be overly focused on achieving a perfect standing wave in the UV section; it's good enough if it's close.

BH5UNT

yzyyz The line in your image that I don't quite understand is: "25 20 PVC pipe, pipe cap, 25-20 direct connection" , are you referring to the pipe plug?
What are the reasons for the specific parameters of the POM tube?"3 mm"Is it referring to thickness, or is there an input error?
Also, looking at the picture you posted, it seems like the main beam is made up of two sections connected together? I would appreciate your explanation. Thank you!

BH5UNT

yzyyz I discovered that the bolts for the M4 cannot be inserted into the 3mm coupling.

BI1IPB

yzyyz 挺好奇这螺丝是怎么塞到pvc管里的😅

BG2EWI

The main beam of the antenna can be made from PPR pipe. The colored lines on the outside of the pipe can be used to assist in positioning, and if the technique is accurate, you can drill holes with a handheld drill. However, it is still recommended to use a drill press to ensure that all resonators are on the same level.

Felix

Hand-drawn review – excellent!

Furthermore, referring to the diagram, the feed lines connect two 1/4-wavelength antennas via a shield and core, which is a balanced antenna. Therefore, the feed lines should be unbalanced.

Does this connection require a balun?

BH5UNT

Felix The well-known Yagi-Moxon antenna design was created by LY3LP. This is based on a modified version (4I1AWN), primarily involving fine-tuning the width of the Moxon section, as well as detailed descriptions of materials and optimizing the grip for better handling. He also used a different method for creating the holes in the unit. Personally, I believe this configuration is equivalent to a choke balun.

The schematic for 4I1AWN is shown below (the original, clearer diagram was hosted on a WordPress blog, but the image has been removed; I can barely read the English version).

BD3QHP

Learned

BI1NIZ

You need a precise ruler.

Felix

BH5UNT
Thank you very much; I learned a lot.

yzyyz

BH5UNT
The meaning of 25-20 variable diameter.
The main part uses a 25-inch unit, while the front U-shaped extension unit uses a 20-inch unit.
Once you remove the main antenna section, it's ready to use. The front extension part provides better U-band performance, and it connects to the main section using a variable diameter connector.
You can find POM tubes with a diameter of 3mm on Taobao; they are hollow and have just the right size to fit the antenna's vibrator inside.

BG7NOD

I thought it was going to be something like a large, seven or eight-meter high and seven or eight-meter long structure.😂

Hangying

That's great, we can now communicate with satellites.

BG2KAJ

Then I'll build a large one, based on the DK7ZB diagram, which will be a portable HF Yagi antenna.
https://www.qsl.net/dk7zb/portabel/2-element-28ohm.htm

I realized that the aluminum tube section was the best part to work with, while the isolation between the active transducers required a significant investment in multiple fiberglass isolators.

BG8KUQ

BG2KAJ Is this antenna single-segment or multi-segment?

BG2KAJ

BG8KUQ Single-band, but by adjusting the oscillator length and replacing the matching line, a single set of equipment can operate in the 10/12/15/17/20 meter band.

闽ICP备2021006864号-7

闽公网安备35020602002794号互联网举报中心

用户协议隐私政策社区规范积分规则中继规则转载须知
更新日志联系我们常见问题友情链接运营报告赞助

浩奇科技（厦门）有限公司

是无线电，把我们联系在一起