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CCD短波天线 [复制链接]

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离线bg7igi
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只看该作者 100楼 发表于: 2022-03-15
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电离层:从昨天到今天从测量和通联测试结果来看,60/40米低架双频段端馈CCD天线的目标基本实现了,信号基本对等,效率很好,今天和架设同样高度(平均1.6米)的60米频段端馈天线AB切换对比来看,CCD是5 .. (2022-01-30 18:56) 

学习了,这样的天线很不错!
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离线电离层
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只看该作者 101楼 发表于: 2022-07-08
通过几个月的间断测试,端馈的CCD天线效率也挺好。
BG2ALB   电波
在线大傻
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只看该作者 102楼 发表于: 2022-07-08
These antennas are basically like a standard dipole in shape and how you feed it, however, they are typically closer to full-wave than half-wave.  The design allows for a standard match with a 52-ohm coax feed and is VERY resonant on the bands the particular model is designed for.

This is not an all-band antenna.  Basically, it’s not a jack of all trades, it is a master at one, or in this case, two bands.  Yep, it’ll work on other bands with a tuner…so will bed springs.  Just remember, the more resonant it is on the bands it’s designed for, the less resonant it’ll be on other bands.  Unlike most antennas, these are not harmonically driven.

instructions.

———————

The CCD is basically a dipole design but with breaks at very precise intervals with silver mica capacitors.  There is a chart below showing the various bands with lengths and values.

Boards:

The key to making the CCD is the insulator boards to mount the caps and wire to.  These boards are available from Far Circuits.  Each board is 1” x .5” and has mounting holes for 14 gauge wire on the ends and smaller holes for mounting the silver mica caps in the middle.

Earlier designs of the CCD had resistors to protect the caps from static discharge.  These boards were designed with a narrow gap between the two pads to allow for arc over and protect the caps in sand and lightning storms.  

Capacitors:

The capacitors are 500v silver mico caps and are available from Just Radios in Canada.  They are high quality and typically 5%.  The antenna, according to the computer model, could handle twice the legal limit.  BUT IT CAN’T.  We suggest 300 watts carrier modes and 800 PEP.  No, you can’t just put 1kv versions in and expect more power capability.  We tried.  They pop.  The reason we found was the internal resistance of the caps will heat them up and they will eventually blow.  500v and kV capacitors have basically the same resistance and will pop at about the same levels of RF.

Wire:

We used the 14 gauge 19 strand slinky wire and if you can find it, use it.  Great stuff, but the manufacturing gods decided to stop making it.  Any 14 gauge should work.  The best is bar wire and copper-clad steel so it won’t stretch as much.  Bar because stripping the wire for each connection is going to bring about four-letter words.  And stripping may nick the wire reducing the overall strength of the antenna.

The Balun and end insulators:

We used a standard W2AU 4:1 balun.  They worked just fine and can be ordered from just about any radio dealer.  The end insulators are simply that.  Nothing special about them at all.

BUILDING INSTRUCTIONS:

Visit the chart below to see the capacitor count and wire lengths needed for the bands you want to build for.  These instructions will work for any of them.

To build the antenna using the boards we highly recommend a ‘jig’ to make sure the distances are measured perfectly.  For example, if the distance is 57” it means center to center.  So, from center roof one board to the center of the next board it should be exactly 57”.  And in the center where the balun goes, it’s 57” from the center of the board to the center of the balun.  And on the ends, it’s 57” from the center of the last board to the end of the loop in whatever insulator you use.

The first step is to install a cap in each board.  The 500v caps should fit in the smaller holes that are closest together.  Always insert caps and wire in from the non-metal side of the board and solder on the metal side with standard ROSIN core solder.  If you are new to this, acid core is for plumbers, but electrical soldering.  Insert the caps as far and evenly into each hole as you can.  Don’t lay them flat.  Solder so that the board and wire is hot enough to melt the solder themselves and let it flow.  Don’t allow any gaps or open areas around the solder joint.  This is going to be swinging in the weather and corrosion will grab a hold in any crevice it can find.

The boards, as you’ll notice, can actually fit in a 1” slot and the cap and wire holes are on one edge.  This is designed so they can fit in a two slots exactly the right distance apart when building them.  As each board is finished it takes the place of the far board and a new one is put in the slot and the next measurement is done for you by your ‘jig’.  So, building the jig you use a Dremel tool with a small router attachment and cut slots for the boards in a single board that is slightly longer than what you need.  For example, if we need a 57” jig we would find a 65”+ board and cut two slots in it with the router to be exactly 57” from center to center.  Make the slots narrow enough for the boards to just fit.  Now you are ready to build.  And your antenna will be very close to perfect in length.

Images showing the jig we used can be found on the CCDantennas.com site under ‘Specs to build a CCD Antenna’.

When attaching the wire to the boards it’s important to cut them to length before soldering.  Leave enough to get through the hole and leave maybe a 1/16th inch amount of wire sticking through to the metal side of the board.  Bend the leads to be right angles to the board just as it will be when it’s in the air.  You might need some weights to hold things in place as you solder, although the board should be in the jig and one end taught from the other end of the jig.  Now, solder very carefully making sure the wire and board get more than hot enough to melt the solder on their own.  Apply a generous amount of solder and allow it to wick through the hold and into the bend you made in each wire.  This makes for a VERY strong connection.  Again, don’t allow for ANY gaps between the wire and board.  The solder connection should be smooth and shiny all the way around the connection.

To make sure you don’t go overboard and install to many caps, count them out and only have the exact number for each leg as you are building it.  Start at one end and work towards the balun.  When you run out of boards for the one leg you know it’s time to install the balun.  THEN you can bring out the other hand of the boards and finish building your antenna.

As you build you should check with a capacitor setting on most multimeters and test across the board right after you build it.  It will not show the proper capacitance BUT it will show you generally the same number across each one.  Or, if the board has a problem, it’ll show a short.  Or if your soldering job needs work it might show an open.  Best to test this baby now than have to haul it back down the tower later.
在线bg3xx
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只看该作者 103楼 发表于: 2022-07-08
应该翻译过来再发的。这种乾坤大挪移的原版英文帖子和B站的原版英文无线电技术讲解视频一样,基本一滑而过。
离线bg2lim
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只看该作者 104楼 发表于: 2022-08-18
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电离层:通过几个月的间断测试,端馈的CCD天线效率也挺好。[表情]  (2022-07-08 10:41) 

可以分享下数据吗?非常想做一个端馈类型的,中间馈电的馈线太不好架设了
离线电离层
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只看该作者 105楼 发表于: 2022-09-19
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bg2lim:可以分享下数据吗?非常想做一个端馈类型的,中间馈电的馈线太不好架设了[表情] (2022-08-18 01:32) 

我是试用的16:1巴伦,还有些问题,,还得测试
BG2ALB   电波
在线BD7JAC
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只看该作者 106楼 发表于: 2022-09-20
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bg3xx:应该翻译过来再发的。这种乾坤大挪移的原版英文帖子和B站的原版英文无线电技术讲解视频一样,基本一滑而过。 (2022-07-08 23:37) 

我也不懂英文,自己动动手指用网页翻译一下也能看个八九成,能分享就好,当然翻译之后更好,但没必要苛求。
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离线电离层
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只看该作者 107楼 发表于: 2022-10-08
BG2ALB   电波
离线bd2bh
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只看该作者 108楼 发表于: 2022-10-12
偶尔看到了CCD天线,感觉制作、调试太复杂了。

其实说其古老的天线,既可靠,好用,又容易制作的HF天线是W3DZZ天线。

----5波段偶极谐振天线!
BD2BH 一路同行,Your country needs you.
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离线bd2dd
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只看该作者 109楼 发表于: 2022-10-13
五波段(陷波器式)水平偶极天线的制作

摘要: 这是一种被称为W3DZZ的五波段水平偶极子天线,可工作于80米、40米、20米、15米和10米波段,基本涵盖了常用的HF业余频率。笔者根据台湾《无线电界》1994年的一篇文章介绍制作了一付这样的天线。制作中难度最大的是LC并联谐振陷波器,业余条件下进行调校比较费时费工。天线尺寸如图1所示。LC陷波器的制作与调试方法如下:1、取青灰色酚醛塑料管一根,外径Φ48m
    这是一种被称为W3DZZ的五波段水平偶极子天线,可工作于80米、40米、20米、15米和10米波段,基本涵盖了常用的HF业余频率。
笔者根据台湾《无线电界》1994年的一篇文章介绍制作了一付这样的天线。制作中难度最大的是LC并联谐振陷波器,业余条件下进行调校比较费时费工。
天线尺寸如图1所示。
LC陷波器的制作与调试方法如下:
1、取青灰色酚醛塑料管一根,外径Φ48mm,壁厚不小于3mm,以保证有一定的机械强度。割二段,每段长50mm,夹在车床上车制螺纹槽,螺距2mm,槽深1mm,左旋或右旋均可。
2、取Φ1.76mm无氧铜线6M,分为二段,每段3M。
3、于带螺纹槽的管子二端适当位置钻Φ2.5mm的孔若干。
4、用Φ1.76线在管子上槽内绕制线圈,要拉紧绕平。每只线圈绕12-15圈左右,管上预留孔备作线圈圈数调整之用。
5、线圈电感量测定:每只线圈的电感量约为8.3&mICro;H。有电感测试仪可直接测量。无条件者可参照CRSA《CQ》2000年第3期笔者的文章《简易电感测试仪》进行测定和计算。我即是用这种土方法测之,精度足够。两只线圈的电感量应基本一致。
6、电容器及电容量测定:选用120pF/500V云母电容4只,每二只串联后使用,容量必须在数字表上测准并配对。云母电容器的温度稳定性较好,业余条件下尚无其它电容可以替代。
7、L、C之组合:将串接的电容放入线圈管子的内腔,与L并接。LC组合后每端留30mm线待与天线A、B段相连。
8、陷波器谐振频率的测定:将LC谐振器用最短的连线接入图二所示的电路中。业余条件可用收发信机低功率档(2W以下)送7.050MHz的调幅信号至电路中,记录高频毫伏表显示的数值,然后按1KHz的步进,调节信号频率,看在哪一个频率点上毫伏值最大。最大值点处,即是LC并联谐振的频率。我们所需频点为7050KHz,高于或低于这个频率,均需对L作圈数的调整。因此,该谐振器的校正颇费时间,一定要有耐心。两只谐振器的谐振频率必须一致。
全天线的调整:将二根A段接上馈电缆,升入一定高度,用修剪法使之谐振于7.050MHz,接上LC陷波器,再测定一次,修整到7.050MHz的SWR最低。接上B段,使全天线谐振于3.535MHz,即告完毕。
天线的三部分连接工艺也是关键。笔者无条件用喷灯焊接,全部采用现场螺钉压接,这样在屋顶上作业调校较为方便。LC陷波器的引接线是天线振子的组成部分,不可忽略。所有接点均用AB胶封死,以防氧化。
笔者按上述方法,架设的天线于1999年6月投入使用,天线总长度40米(含两端拉线),两端杆高3.5米,架设于住宅六楼顶。由于10米段频带较宽,SWR起伏较大,最高2.8 ,最低1.7 ,其它波段均在1.8以下。三年多来使用正常,天线未接用巴伦,QRP时情况亦佳。该天线的缺点是架设需要一定的场地。

这个天线制作起来,也挺复杂!


离线bd2bh
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只看该作者 110楼 发表于: 2022-10-14
http://www.on5au.be/content/a10/wire/ccd-1.gif


BD2BH 一路同行,Your country needs you.
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离线电离层
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只看该作者 111楼 发表于: 2022-10-16
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bd2bh:偶尔看到了CCD天线,感觉制作、调试太复杂了。
其实说其古老的天线,既可靠,好用,又容易制作的HF天线是W3DZZ天线。
----5波段偶极谐振天线![图片] (2022-10-12 19:38) 

CCD天线的核心优势应该是振子上电流分布均匀,电压峰值小,由此带来的对架设高度不敏感,振子形状不敏感,对周围物体不敏感等等,就是太长了,不适合楼区住宅架设。
BG2ALB   电波
在线大傻
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只看该作者 112楼 发表于: 2023-09-28
The CCD is a viable and potentially useful antenna of its type. Whether the advantages warrant the relatively complex construction compared to simpler wire antennas is a user judgment.

CCD是一个可行的和潜在的有用的天线的类型。与简单的有线天线相比,这些优势跟相对复杂的结构是否值得全凭用户的判断。