Re: J-pole dimensions using 450-ohm window line resenting reply


Henry Taylor <hank008@...>
 

Fred's note refers to a j-pole.  J-poles are a good way to go for 2-meter for 3 reasons (at least) - cheap, effective, and scaleable.  Fred's design using 450 ohm ladder line is the smallest and most portable I have ever seen .  Larger ones made of copper tubing are also cheap and less tricky to tune, but still sort of portable.

I would recommend that you get with Fred and make up the 450 ohm one as a good start.  You are welcome to my stash.

As an admitted noobie, you are in for "the ride" into the black art (almost) of antenna design.  Mostly we all start with cheap and simple and evolve into personal circumstances and needs.  You will find an abundance of expertise and help from the CMRA / BCARES group.  Online sources are also great.  Allow me to encourage you on.

Hank

泰 勒
大胡子

On Oct 11, 2018, at 09:25, William Johnson <Wdjohnson81@...> wrote:

Yes sir I got thru, I don't know exactly how much I would personally need.  I haven't ever built any antenna's.  I am looking up plans now online to see how much I would need for a couple different types.


73

Will  KE0PKO 

On Thu, Oct 11, 2018 at 7:54 AM Henry Taylor <hank008@...> wrote:
Did this get thru?  Sending again

How much do you need.? I got quite a bit left over.  Don't know exactly how much but I just looked at it and it's a sizeable roll.  I have a j-pole made of this (made by Fred, in fact) and it's only a yard or so in length.  I think I have enough for dozens, at that size.

Free for the taking, but I don' t get out much (health problems) so you might have to come out and get it.

Hank. KD0BVQ

泰 勒
大胡子

> On Oct 10, 2018, at 13:38, Ernest Shaw <ernest_s@...> wrote:
>
> Related,
> Does anyone have a stockpile of 450 - ohm window line they are looking to sell off short sections?  Or are we best off going online and ordering our own stash?
>
> Ernest
>> On Oct 10, 2018, at 12:41 PM, Fred Dittrich <fdittric@...> wrote:
>>
>> Hi
>>
>> The subject of j-poles constructed out of window line came up at lunch. From my notes of 4/1/16 here are the dimensions to center on 146 MHz as measured from the bottom and verified by my AA-600:
>>
>> Where: Unmolested window line is at the bottom and one conductor only continues above that section.
>>
>> Short the "bottom" of the j-pole, and measure up from there:
>> 30 mm from bottom - this is the 50 ohm coax attachment point
>> 453 mm from bottom - this is where you remove one of the conductors all the way to to the top
>> 1402 mm from the bottom - this is the top of the j-pole
>>
>> Enjoy
>>
>> 73
>>
>> Fred AE0FD
>
>
>
>




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