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