I have a couple J-poles enclosed in PVC and they work just fine. I don't
know the gain figures on them but I can say I compared one of them side by
side with my old diamond X200 and couldn't tell the difference. Now I use
that one on packet and at the same height as a diamond X50 on a radio my
wife sometimes uses, I think the J-pole has a little edge, it's just made
with ladder line in a PVC pipe. Someone used to sell them, I bought one of
his then made the other myself. I'm not sure which I have up because they're
identical and the other is sitting in the shed somewhere.
----- Original Message -----
From: "Neil k8it" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Tuesday, April 28, 2015 5:38 PM
Subject: Re: plans for high gain 2m 70cm antenna
> Well considering these comments about the diamond antennas what kind of
> antenna can I build that will meeet these goals.
>
> 1. totally enclosed in pvc pipe
> high gain - about 6dB on 2m and 8 to 9dB on 70cm
> length less than 12 feet long
> a jpole creates a pvc covering issue for the first two foot or so where
> the
> j is located
>
>
> --------------------------------------------------
> From: "John Miller" <[log in to unmask]>
> Sent: Tuesday, April 28, 2015 4:54 PM
> To: <[log in to unmask]>
> Subject: Re: plans for high gain 2m 70cm antenna
>
>> I've pulled a couple of them apart as well, let's put it this way, I'll
>> gladly build my antennas. J-poles, dipoles, easy verticals and even on up
>> to
>> I want to build a hex beam someday just so I can say I did. I've rebuilt
>> my
>> 2 meter beam and have full confidence I could build my next one from
>> scratch
>> and even make changes to make it go to 70 CM, 900 MHz, 220, maybe even 6
>> meters or all the way down to 20. The X200 and I assume the 300 is the
>> same,
>> is a pretty complex antenna in all the coils and what not and having seen
>> that I'm not sure how they work as well as they do without much if any
>> trouble. I wouldn't want to build one.
>> ----- Original Message -----
>> From: "Colin McDonald" <[log in to unmask]>
>> To: <[log in to unmask]>
>> Sent: Tuesday, April 28, 2015 4:33 PM
>> Subject: Re: plans for high gain 2m 70cm antenna
>>
>>
>>> I've pulled a couple of these apart.
>>> There are multiple matching coils, loading coils and various element
>>> arrangements all the way up the antenna.
>>> It's not a simple thing to build.
>>> far easier to build a yaggie or quad for those bands.
>>> I expect it would also be more expensive to build something like the
>>> x200/300 as well than it is to buy one.
>>>
>>> 73
>>> Colin, V A6BKX
>>> -----Original Message-----
>>> From: Neil k8it
>>> Sent: Tuesday, April 28, 2015 2:24 PM
>>> To: [log in to unmask]
>>> Subject: Re: plans for high gain 2m 70cm antenna
>>>
>>> I have been thinking of building a base station 2m and 70cm antenna. I
>>> like
>>> the diamond x-200a or x-300a designs but would like to try building one
>>> myself. the antennas are rated at 6 to 6.5 dB on 2m and 8 to 9.5 dB on
>>> 70cm.
>>> But does anybody have dimensions of this type of antenna? I found
>>> several
>>> J-pole designs but no 5/8 wave collinear designs with radials similar to
>>> the
>>> Diamond x-200A or x-300A antennas.
>>> Anybody have any thoughts?
>>>
>>> Would a 8 foot center element (two 5/8 waves in series simply work?
>>> would
>>> it
>>> match to 50 ohm coax? will it match on 70cm?
>>>
>>> thanks
>>> 73 Neil k8it
>>
>>
>> -----
>> No virus found in this message.
>> Checked by AVG - www.avg.com
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>>
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