I disagree with Grant. I lifted the bottom parts of three different 200
footers, one Rohn 55 and two Rohn 65 with the K0XG rings on them. The Rohn 55
bottom was 60 feet with one ring. The Rohn 65s were 130 feet with two rings on
each. No problems with a good crane op. We did not hook to the rings of
course and just in case things went wacky I wired the top and the bottom of the
rings together, which proved to be unnecessary.
The whole affair was picked and set on a K0XG rotating base. I used three
other people to help since the guys were the stiff Polyrod rather than
Phillystran. With a 60 footer, in a pinch, you could get by with just one
person. This worked so well I will probably use this method on my planned 90
footer of Rohn 55 with two rings out in KH6 if I can get a crane into the area.
Bill K4XS/KH7XS
> Since my largest tower went up with a commercial tower company who
> builds 400' plus towers, and who required the base be managed, I would
> say there are definite disagreements about this. When lifting sections
> with rings off supports, it can't be done safely and reliably, no matter
> the skill of the crane op. A plain stick of Rohn 25/45/55 is a
> different animal. Note the thread origin is about tower sections with
> rings already mounted.
>
> Grant KZ1W
-----Original Message-----
From: towertalk-request <towertalk-request@contesting.com>
To: towertalk <towertalk@contesting.com>
Sent: Tue, Oct 18, 2016 3:38 am
Subject: TowerTalk Digest, Vol 166, Issue 57
Send TowerTalk mailing list submissions to
towertalk@contesting.com
To subscribe or unsubscribe via the World Wide Web, visit
http://lists.contesting.com/mailman/listinfo/towertalk
or, via email, send a message with subject or body 'help' to
towertalk-request@contesting.com
You can reach the person managing the list at
towertalk-owner@contesting.com
When replying, please edit your Subject line so it is more specific
than "Re: Contents of TowerTalk digest..."
Today's Topics:
1. use of a basket when antenna just above a K0XG ring (StellarCAT)
2. Re: Legs of a 60' piece of tower being dragged while being
lifted (Steve Maki)
3. Re: Legs of a 60' piece of tower being dragged while being
lifted (Grant Saviers)
4. Re: Legs of a 60' piece of tower being dragged while being
lifted (Steve Maki)
5. Re: Voltage at ends of yogi parasitic elements? (Rob Katz)
----------------------------------------------------------------------
Message: 1
Date: Mon, 17 Oct 2016 20:42:08 -0400
From: "StellarCAT" <rxdesign@ssvecnet.com>
To: "tower" <towertalk@contesting.com>
Subject: [TowerTalk] use of a basket when antenna just above a K0XG
ring
Message-ID: <0BE47700B55648139D388148C18EFAAC@RXDesignDell>
Content-Type: text/plain; charset="utf-8"
The crane rep came out to check out my site ? per my request ? everything is a
go. I asked him about the use of a basket explaining and showing him the rings
and their arms ... and the fact that the antennas really need to be all the way
up against the tower ? he agreed the basket would not allow that.
just an FYI for anyone considering this. Again this was when a guy was ?in the
way? ? not in open space on the tower.
Gary
K9RX
ran a trencher for 7 hours yesterday ? 800# monster ... it cut a 4? width ?
JUST ... and the corex 4? tubing is 5? in diameter. SO I had to go back over it
all again (this is VERY hard packed clay ? like rock ? oh and rock as well) ...
that was fun trying to pull the beast to the side so that it would cut
additional width as opposed to its desire to just stay in the middle.
today was spent running HL, coax, and control cables through 140? of the Corex
... managed 8 cables (including one run each 7/8?, 5/8?, 1/2? HL and one coax)
and couldn?t pull any more through ... I?ll need to hook up the tractor to get
the remaining 3 cables through.
tomorrow is pulling 5 more runs from that tower to the main tower ... HL, coax,
control cables.
POOPED. Friday is my day ... coming fast now.
------------------------------
Message: 2
Date: Mon, 17 Oct 2016 21:55:00 -0400
From: Steve Maki <lists@oakcom.org>
To: towertalk <towertalk@contesting.com>
Subject: Re: [TowerTalk] Legs of a 60' piece of tower being dragged
while being lifted
Message-ID: <322dad7d-46c9-5955-0d09-1fc6055465a9@oakcom.org>
Content-Type: text/plain; charset=windows-1252; format=flowed
On 10/17/2016 11:53 AM, john@kk9a.com wrote:
> The weight is irrelevant. A skilled crane operator can move the boom as
> it is being lifted leaving the section on the ground as a pivot point.
> Of course if someone wishes to build a slide or use a loader to move
> the base as it is being lifted that is perfectly fine, but I won't be
> doing this.
>
> John KK9A
I agree. A good operator has no problem at all with this scenario, as
long as the crane is sized properly and can be positioned properly.
It's just a non-issue.
-Steve K8LX
------------------------------
Message: 3
Date: Mon, 17 Oct 2016 19:39:27 -0700
From: Grant Saviers <grants2@pacbell.net>
To: Steve Maki <lists@oakcom.org>, towertalk
<towertalk@contesting.com>
Subject: Re: [TowerTalk] Legs of a 60' piece of tower being dragged
while being lifted
Message-ID: <58058B5F.2020707@pacbell.net>
Content-Type: text/plain; charset=windows-1252; format=flowed
Since my largest tower went up with a commercial tower company who
builds 400' plus towers, and who required the base be managed, I would
say there are definite disagreements about this. When lifting sections
with rings off supports, it can't be done safely and reliably, no matter
the skill of the crane op. A plain stick of Rohn 25/45/55 is a
different animal. Note the thread origin is about tower sections with
rings already mounted.
Grant KZ1W
On 10/17/2016 18:55 PM, Steve Maki wrote:
> On 10/17/2016 11:53 AM, john@kk9a.com wrote:
>
>> The weight is irrelevant. A skilled crane operator can move the boom as
>> it is being lifted leaving the section on the ground as a pivot point.
>> Of course if someone wishes to build a slide or use a loader to move
>> the base as it is being lifted that is perfectly fine, but I won't be
>> doing this.
>>
>> John KK9A
>
> I agree. A good operator has no problem at all with this scenario, as
> long as the crane is sized properly and can be positioned properly.
>
> It's just a non-issue.
>
> -Steve K8LX
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
------------------------------
Message: 4
Date: Mon, 17 Oct 2016 22:55:07 -0400
From: Steve Maki <lists@oakcom.org>
To: towertalk <towertalk@contesting.com>
Subject: Re: [TowerTalk] Legs of a 60' piece of tower being dragged
while being lifted
Message-ID: <e0ff1078-6076-4a42-4164-a75bb5c48226@oakcom.org>
Content-Type: text/plain; charset=windows-1252; format=flowed
Hmm. All I can say is we install much larger pieces of assembled tower
than R55 (and 50' pieces of monopole weighing many thousands of pounds
for that matter), and crane operators seem to have no problem picking
the tower from the top end and standing it up straight without dragging
it. It seems to be second nature with these guys.
I can't quite visualize how rings complicate things that much if you
have the base on the ground and the tower tipped up on a support 2/3 or
so up the tower.
-Steve K8LX
On 10/17/2016 22:39 PM, Grant Saviers wrote:
> Since my largest tower went up with a commercial tower company who
> builds 400' plus towers, and who required the base be managed, I would
> say there are definite disagreements about this. When lifting sections
> with rings off supports, it can't be done safely and reliably, no matter
> the skill of the crane op. A plain stick of Rohn 25/45/55 is a
> different animal. Note the thread origin is about tower sections with
> rings already mounted.
>
> Grant KZ1W
>
> On 10/17/2016 18:55 PM, Steve Maki wrote:
>> On 10/17/2016 11:53 AM, john@kk9a.com wrote:
>>
>>> The weight is irrelevant. A skilled crane operator can move the boom as
>>> it is being lifted leaving the section on the ground as a pivot point.
>>> Of course if someone wishes to build a slide or use a loader to move
>>> the base as it is being lifted that is perfectly fine, but I won't be
>>> doing this.
>>>
>>> John KK9A
>>
>> I agree. A good operator has no problem at all with this scenario, as
>> long as the crane is sized properly and can be positioned properly.
>>
>> It's just a non-issue.
>>
>> -Steve K8LX
------------------------------
Message: 5
Date: Mon, 17 Oct 2016 11:52:13 -0400
From: Rob Katz <rob.katz@thelegacycenter.com>
To: Hardy Landskov <n7rt@cox.net>
Cc: towertalk@contesting.com
Subject: Re: [TowerTalk] Voltage at ends of yogi parasitic elements?
Message-ID: <485ABA69-14A4-488F-88AC-B3765AC6424F@GeekLeadership.com>
Content-Type: text/plain; charset=utf-8
Thank you Hardy and everybody for your responses. I?ve built many wire yagis
that are loaded in the middle. I?m looking to put up a new 3-el on 40m with a
rope catenary as the ?boom,? so I want to eliminate the weight in the middle to
reduce the sag. It?s also over my driveway, so I don?t know if dropping
open-wire line would pass the XYL test :-) It looks like the end voltage would
be too high for relays, but I?m still curious to have a number on that voltage
if someone can figure it out.
I appreciate all the generous folks in this group!
73,
Rob K4OV
> On Oct 17, 2016, at 06:46, Hardy Landskov <n7rt@cox.net> wrote:
>
> Rob,
> I would switch in an inductor for a reflector and a capacitor for a director
> at the CENTER of the element. Use a shorted stub for the reflector and an
> open wire stub for the director.
> The voltage at the ends is very high even in parasitic elements and you would
> have the problem of RF getting into the switching wires. Not many relays will
> survive that environment and I don't know anyone who has tried that.
> I would try running 1/2 wave open wire line down to the ground and switch in
> the lumped elements there. Then put lumped elements in at the antenna. Of
> course you need split parasitic elements.
> I have built 2 el 80 meter Yagis with a DE and Reflector using open wire
> line(1/2 inch Al tubing) back to the center of the antenna so I could reach
> the stub and adjust the shorting coil for F/B ratio. Then used a latching
> relay to short out a portion of the line to go to the fone band. Of course a
> matching network would have to be switched in going from CW to FONE.
> But if you are working with wires, a spring loaded knife switch will work.
> But you would have to go out to the tower to change directions.
> I think I remember one guy who used retractable radio antennas from cars in a
> junk yard.
> And there is SteppIR if your VISA card can stand the hit.
>
> I would be interested in other solutions myself.
> Hardy N7RT/4
>
>
> -----Original Message-----
> From: TowerTalk [mailto:towertalk-bounces@contesting.com] On Behalf Of Rob
> Katz
> Sent: Sunday, October 16, 2016 11:09 PM
> To: towertalk@contesting.com
> Subject: [TowerTalk] Voltage at ends of yogi parasitic elements?
>
> I?m playing with some wire yagis, and I?d like to put relays at the ends of
> the parasitic wires to switch the director to a reflector (and vice versa).
> If I?m driving the antennas with a full 1.5 KW, what would be the maximum
> voltage that I can expect at the ends of the PARASITIC elements? Even a
> rough estimate would be useful, I just need to get a sense of what kind of a
> relay I would need to use.
>
> 73,
> Rob K4OV
>
> --
>
> Rob Katz, Senior Partner
> 919-219-5324
>
>
>
>
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
------------------------------
Subject: Digest Footer
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
------------------------------
End of TowerTalk Digest, Vol 166, Issue 57
******************************************
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|