That is a good idea. Thanks.
73
Butch
WA0VJR
Node 3148
Wallace, ks.
On Tue, 28 Apr 2015, Colin McDonald wrote:
> One pretty quick and easy way to deal with this one bolt issue, which many
> base station style antennas have, is to put a few wraps of vulcanizing tape
> around that area of the mount. This will keep water away from the coaxial
> connecter inside the tube at the base of the antenna as well...I use
> vulcanizing rubber tape at the joints of the antenna, and at the base,
> especially around that one bolt holding the antenna into the tube because I
> saw right away when I first got the antenna how it would be a pretty obvious
> problem after a while.There is supposed to be a lock washer with that little
> bolt, but due to the fact that you are going into aluminum, the bolt tends
> to strip if you tork too hard...so the tape keeps the bolt in place even if
> it loosens off a bit.
>
> Regards
> Colin
>
> From: John Miller
> Sent: Tuesday, April 28, 2015 5:31 PM
> To: [log in to unmask]
> Subject: Re: plans for high gain 2m 70cm antenna
>
> I've had a couple commet antennas including the one I have up currently for
> 900 MHz and they're exactly the same as the diamond in that aspect. Maybe
> not all of them are but the 2 I've had over the years were/are. I don't have
> the dual bander anymore, I sold that but the 900 MHz one is still up and
> going. Anyway though, both of them had the sleeve like the diamonds to and
> the one small bolt holding the antenna in the sleeve. In fact, looking at
> them side by side you'd never know the difference in brand. I also have a
> tram UHF antenna I used to use on GMRS, right now it's in the shed because I
> don't have the GMRS license anymore and 70CM is dead around here or I could
> easily retune it for there but that is also exactly the same mounting system
> and to my knowledge I've never lost one of those bolts though I have heard
> of other people having that problem. I haven't checked the diamond X50 in a
> couple years so it may have happened to that one but I know it's still up
> there anyway. I have a diamond X30 up as well for my scanner which was
> completely rebuilt but that just went up recently and it's very low so
> shouldn't get much wind or anything.
> ----- Original Message -----
> From: "Butch Bussen" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Tuesday, April 28, 2015 6:19 PM
> Subject: Re: plans for high gain 2m 70cm antenna
>
>
>> I recently bought a diamond 210 and when we got it put together, I found
>> diamond has what I consider a main design flaw. The last dual bander I
>> had up was a comet, I don't recall the model. I didn't realize until I
>> got this last diamond. I'll try and describe the problem. At the
>> bottom of the diamond right below the radials is a round piece about 2
>> inches long and at the bottom of this is where the coax connects. This
>> piece sets inside a piece of tubing a foot and a half long and this
>> piece is where the mounting hardware goes that mounts the antenna to the
>> mast. All that holds that hole top part of the antenna in place is a
>> small bolt that goes through a hole in the pipe and screws into the
>> round piece that slides inside. Hope that makes sense. The problem is
>> (this happened to me 2 or 3 times in Vegas, is vibration shakes this
>> bolt out and then the antenna just wobbles around inside this tubing.
>> If they insist on mounting it this way, there should be bolts. What I
>> did to fix my uhf one in vegas was to cut an x or cross in the outside
>> tubing with a hack saw and put on a hose clamp. This held the bolt in
>> and also compressed the tubing against the inside part. A poor design
>> as far as I'm concerned. Commit is totally different and much better.
>> I'll never buy another diamond.
>> 73
>> Butch
>> WA0VJR
>> Node 3148
>> Wallace, ks.
>>
>>
>> On Tue, 28 Apr 2015, Colin McDonald wrote:
>>
>>> 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
>>>
>>>
>
>
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