In my humble opinion.:
Jerry,
The choices for mastingare very high. Weight and wind load is critical
for a ROHN 25 tower. I used, for 35+ years, a 20 foot 2" [OD] thick
wall aluminum conduit for my mast in a 60' ROHN 25 w/a Ham M rotor. It
was guyed at 3 levels using Torque bars and insulators on them. The
tower was also a Vertical. It supported 3 Hy-Gain beams .They were a a
TH6-DX, a 6 Element 6 Meter beam and a 10 Element 2 meter beam. A 65 MPH
strait line wind brought down a near by ASH tree limb, that hit the
middle of the tower and my pride & joy antenna system was dead crumpled
on the roof. The mast didn't change shape at all and is being reused.
I use 'Metal Super Market' in Dallas for most of my metal antenna
needs. Irving is mid way [15 miles] between Dallas & Ft Worth, Texas.
I looked up your call on QRZ.com if it is correct, and found your Zip
Code of 94553. I entered it into the www.metalsupermarkets.com web
page on it's page 2. The nearest location for one of their stores is in
Hayward, Ca. [Their Zip code was not indicated]. Their email is:
hayward@supermarkets.com. Their address is: 2301 Industrial Parkway
West, Hayward, CA. Phone #: 510-259-1005. The alternate location in
your area is @ 705 Comstock Street, in Santa Clara, CA. Their number is:
408-654-9177. Their email is: santaclara@metalsupermarkets.com. I am
an Electronics type and not a mechanical engineer but why black pipe or
85 PSI needed for antenna mast. They bend and stay in it's last position
with high wind bursts. My mast was always bending with high winds but
always returned to normal after the high winds [or tornado's went by].
Hee hee hee The 6061 is available in 1/8" or 1/4". They have many
stores all around the states. Always ask for FOB pickup point unless
shipping is inexpensive to your needs or some one else is paying the fare.
Good luck. I hope I have helped. (Being an ex-California ham [KN6/K6DFJ
1st in 1953]).
Please reply to: dariise@verizon.net if I was or I was not of any help.
The Dallas area winds are about peek at 65 - 75 MPH [if not in a direct
line of a Tornado which can be what ever God wishes at the time]. Hee
hee hee
73's,
Dennis, K5AVT
On 1/5/2013 7:43 AM, towertalk-request@contesting.com wrote:
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. Re: Source for 2" OD Mast (Grant Saviers)
2. Re: Bye Bye Birdies (Grant Saviers)
3. Re: Source for 2" OD Mast (Jon Pearl - W4ABC)
4. Horizontal Loop Performance?? (Edward Sylvester)
5. Re: Source for 2" OD Mast (K1TTT)
6. Help with rotor valuation, Telrex (Matrin Sole)
7. Re: Help with rotor valuation, Telrex (K1TTT)
----------------------------------------------------------------------
Message: 1
Date: Fri, 04 Jan 2013 17:21:27 -0800
From: Grant Saviers <grants2@pacbell.net>
To: Jerry Gardner <jerryw6uv@gmail.com>, towertalk@contesting.com
Subject: Re: [TowerTalk] Source for 2" OD Mast
Message-ID: <50E78017.1080906@pacbell.net>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
see my earlier post also. I forgot to mention A513 DOM tube which has a
little less yield than normalized 4130 with 72kpsi yield at about 40% of
the cost. I use it when high yield stuff is needed. Jorgensen might
have it, onlinemetals here in Seattle stocks it, pretty convenient for me.
One more thought - wander through SIMS Metal (recycling) on south 1st st
(1900 Monterey) in San Jose (next door and north of the junk recycling
yard). I've found 4130 & 4140 which they sell for the usual recycle
$/lb for scrap usable steel. It's a matter of luck if the stuff is
marked, but worth a try. Also, there is a lot of aluminum and they sell
new small structural hot rolled steel up to 4x4 square and 6" WF beams.
Sometimes there is a lot of drill pipe which is a pretty strong (and
hard alloy), nice to build 35' masts for stuff.
Grant KZ1W
On 1/4/2013 12:26 PM, Jerry Gardner wrote:
Anyone know of a source for a 2" OD 5 to 20 foot steel mast in the
vicinity of the S.F. Bay Area? Something with around 87 k psi yield
strength would be ideal.
Lots of on-line places sell these, but the shipping cost is greater than
the cost of the mast itself. If there's someplace close to me that stocks
something suitable, I'll rent a U-Haul truck and go pick it up.
73, Jerry
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
------------------------------
Message: 2
Date: Fri, 04 Jan 2013 17:26:15 -0800
From: Grant Saviers <grants2@pacbell.net>
To: Patrick Greenlee <patrick_g@windstream.net>
Cc: towertalk@contesting.com
Subject: Re: [TowerTalk] Bye Bye Birdies
Message-ID: <50E78137.2000101@pacbell.net>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Patrick
Please suggest some stocking suppliers and models.
Grant KZ1W
On 1/4/2013 10:52 AM, Patrick Greenlee wrote:
Plastic owls and rubber snakes work for some folks but are not
universally successful.
Ultrasonic emissions have a much higher success record. Ultrasonic
waves are easy to "beam" directionally which permits a ground or near
ground level installation with the transducer(s) aimed up to where the
birds like to perch. Aiming the sound upward keeps from disturbing
the dogs and cats.
These devices are available COTS for relatively little money or easily
built by the electronic savvy. Mine have lasted for many years and
still work well. Some of these devices offer choices on the type of
output. A randomly occurring warble tone similar to the "yelping
style" public safety sirens (but of course in the ultrasonic spectrum)
seems to work best. Having it come on at random intervals works best
and keeps the birds from getting used to it.
Inexpensive "tweeters" of the horn variety work well, especially if
the design lends itself to accepting a drain hole for water (well...
it is aimed up) Alternatively an enclosure with a hard flat reflective
surface to aim the beam upward will work.
I have used these for many years with great success, not only for
birds but other pests as well when coupled with IR motion detector
including cats and dogs who used to think my yard a public restroom
and the odd skunk, raccoon, armadillo, or opossum.
Patrick AF5CK
iginal Message----- From: Jim Lux
Sent: Saturday, December 29, 2012 5:16 AM
To: towertalk@contesting.com
Subject: Re: [TowerTalk] Bye Bye Birdies
On 12/28/12 9:11 PM, Bob K6UJ wrote:
Another option for bird control is to get one of the plastic owls and
put him up on the tribander.
My results were negative, evidently the birds in our area aren't
scared of owls because the owl didn't help at all.
When i took it down I discovered the birds had crapped all over it.
:-)
my in-laws experience with their vineyard was that birds are discouraged
by novelty and change. reflective ribbons one week, owls the next, etc.
That doesn't lend itself to antennas
the other strategy which seems to work quite well is to make what ever
it is "not sittable on". those funky plastic spiky things or
string/monofilament.
Of course, neither of the latter are particularly easy to do on
something like a multielement beam, especially if you want it to last
for decades.
For ordinary wire antennas.. I suppose, if you use strong enough copper
clad steel, the birds can just sit on the wire forever.
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
------------------------------
Message: 3
Date: Fri, 04 Jan 2013 20:35:11 -0500
From: Jon Pearl - W4ABC <jonpearl@tampabay.rr.com>
To: EZ Rhino <EZRhino@fastmovers.biz>
Cc: Towertalk <towertalk@contesting.com>
Subject: Re: [TowerTalk] Source for 2" OD Mast
Message-ID: <50E7834F.1090607@tampabay.rr.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Hi Chris.
http://www.w4abc.com/Masts.html
Well... between Christmas, digging up my sewer line and 24 hour shifts
at work -- it's slow in coming. I've had the page up for a few weeks
and was going to get to it during Christmas vacation.
It's always easier to point to one spot where information lies rather
than hunting-up and then sending someone ten links.
73,
Jon
On 1/4/2013 7:17 PM, EZ Rhino wrote:
Somebody aught to put together a "TowerTalk Chronicles", or Tower Talk Wiki, or
something. Not that we don't want to be helpful, but these topics do repeat from time to time.
Maybe it would be good to just say "look it up on the Wiki?"
Or just buy Steve's book, heh. :-)
Chris
KF7P
On Jan 4, 2013, at 17:12 , Rick Karlquist wrote:
N2TK, Tony wrote:
On Fri, Jan 4, 2013 at 1:40 PM, Rick Karlquist
<richard@karlquist.com>wrote:
Also, pipe is never 2" OD. So called 2 inch pipe has a 2.375" OD.
It won't fit most tower hardware.
That goes to show how much I don't know about masts. I'm planning to use a
Rohn TB3 thrust bearing at the top of the tower -- what tubing OD would I
specify to a metal dealer to get something that is compatible with the
Clarification: 2 inch TUBING has an OD of 2 inches
So called 2 inch PIPE has an OD of 2 3/8 inches
You want to buy TUBING for a mast. If what you buy has
an OD of 2 inches, you can be sure it isn't water pipe.
Yes this is confuzing.
Rick N6RK
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
------------------------------
Message: 4
Date: Fri, 4 Jan 2013 23:12:12 -0800 (PST)
From: Edward Sylvester <navydude1962@yahoo.com>
To: towertalk@contesting.com
Cc: topband@contesting.com
Subject: [TowerTalk] Horizontal Loop Performance??
Message-ID:
<1357369932.16595.YahooMailClassic@web120604.mail.ne1.yahoo.com>
Content-Type: text/plain; charset=iso-8859-1
Greetings All!
?
I am in Saudi Arabia and had the opportunity to throw up some wire antennas.? I
put up 30' of fiberglass mast on my 25' roof and installed an 80m INV VEE fed
with open wire line, straight to tuner.? Hears extremely well.? Cannot transmit
until I get a license, which is in the works.
?
I decided to take advantage of some tall coconut trees and installed a
triangular-shaped horizontal loop with >700' of wire fed with open wire line,
up 35-50', taking into account the sagging.? This goes straight into a 1:1 current
balun at ground level.? Coax run is about 6'.? No issues.? Tunes perfectly.
?
I ran some A/B comparisons with the Inv Vee and determined that they are very
similar in performance!
?
I was hoping the Loop would blow away the Inv Vee but was disappointed when
this did not occur.? Has this been your experience?? I have tried to read as
much as possible, but there are varying opinions on loop expectations.?
?
Your opinion would be greatly appreciated.? Frustrated....
?
73,
Ed NI6S (soon to be HZ1xx and QRV on 160m)
------------------------------
Message: 5
Date: Sat, 05 Jan 2013 12:08:11 +0000
From: "K1TTT" <K1TTT@ARRL.NET>
To: "'Towertalk'" <towertalk@contesting.com>
Subject: Re: [TowerTalk] Source for 2" OD Mast
Message-ID: <01b401cdeb3d$55c74eb0$0155ec10$@ARRL.NET>
Content-Type: text/plain; charset=US-ASCII
That's kind of how my tech reference section on my web site got started, but
once the various reflectors got busy and the search engines became better I
stopped updating it. I am now using some real wiki software for other parts
of my web site and could easily create a reference wiki site to allow
external editors to maintain topics... though it would probably be better if
someone with real servers and a fatter pipe did it.
David Robbins K1TTT
e-mail: mailto:k1ttt@arrl.net
web: http://wiki.k1ttt.net
AR-Cluster node: 145.69MHz or telnet://k1ttt.net
-----Original Message-----
From: EZ Rhino [mailto:EZRhino@fastmovers.biz]
Sent: Saturday, January 05, 2013 00:17
To: Towertalk
Subject: Re: [TowerTalk] Source for 2" OD Mast
Somebody aught to put together a "TowerTalk Chronicles", or Tower Talk Wiki,
or something. Not that we don't want to be helpful, but these topics do
repeat from time to time. Maybe it would be good to just say "look it up on
the Wiki?"
Or just buy Steve's book, heh. :-)
Chris
KF7P
On Jan 4, 2013, at 17:12 , Rick Karlquist wrote:
N2TK, Tony wrote:
On Fri, Jan 4, 2013 at 1:40 PM, Rick Karlquist
<richard@karlquist.com>wrote:
Also, pipe is never 2" OD. So called 2 inch pipe has a 2.375" OD.
It won't fit most tower hardware.
That goes to show how much I don't know about masts. I'm planning to
use a Rohn TB3 thrust bearing at the top of the tower -- what tubing
OD would I specify to a metal dealer to get something that is
compatible with the
Clarification: 2 inch TUBING has an OD of 2 inches So called 2 inch PIPE
has an OD of 2 3/8 inches You want to buy TUBING for a mast. If what you
buy has an OD of 2 inches, you can be sure it isn't water pipe.
Yes this is confuzing.
Rick N6RK
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
------------------------------
Message: 6
Date: Sat, 5 Jan 2013 20:05:27 +0700
From: "Matrin Sole" <hs0zed@csloxinfo.com>
To: "'Towertalk'" <towertalk@contesting.com>
Subject: [TowerTalk] Help with rotor valuation, Telrex
Message-ID: <00db01cdeb45$554c58b0$ffe50a10$@csloxinfo.com>
Content-Type: text/plain; charset="us-ascii"
I have a large rotator that I am trying to find information on and some idea
as to value. Since it is really too big for anything I might ever have I
will likely dispose of it if I can figure out a reasonable value. Weighs
about 40kG so unless you live in Thailand I don't think this is for you.
It is a Telrex A3695RISX, that's what it says on the model number label.
Weighs about 40kG, large 1/3 HP Doerr motor driving a 3.5 inch output shaft
by way of two worm drive gearboxes and a 1 inch wide chain. Direction
information is from a General Electric Selsyn coupled to the drive shaft by
a small chain. The whole thing is mounted on an 18 inch by 10 inch steel
plate.
Anybody know anything about these, have any info, or care to offer an
estimate as to likely value?
Thanks
Martin, HS0ZED
------------------------------
Message: 7
Date: Sat, 05 Jan 2013 13:43:45 +0000
From: "K1TTT" <K1TTT@ARRL.NET>
To: "'Towertalk'" <towertalk@contesting.com>
Subject: Re: [TowerTalk] Help with rotor valuation, Telrex
Message-ID: <01bb01cdeb4a$af90c4a0$0eb24de0$@ARRL.NET>
Content-Type: text/plain; charset=US-ASCII
To refresh memories, you asked about this one last year (ain't google
great), and posted a picture at: http://tinyurl.com/78r5nk8
And there is a thread in the archives describing it:
http://lists.contesting.com/archives//html/Towertalk/2012-02/msg00399.html
If the selsyns and motor work and there isn't too much play in the chain
drive I would probably pay $500 for it if someone had it nearby and I had a
use for it. Without a pressing need for it I might invest $250 and spend
some time cleaning it up to resell. It will probably need to be cleaned up
and painted, and maybe have the gear boxes opened up to check for
lubrication and make sure there isn't any water damage in them. The motor
should also probably be checked. One big problem with some of the old
telrex rotors is that they only fit in BIG towers, you can't stuff them into
rohn 25 or similar towers, and they are kind of a waste for small antennas
anyway. This kind of limits the market for them. The use of selsyns also
limits the use of after-market controllers, you have to refit them to use a
pot for indication or use the old controller.
David Robbins K1TTT
e-mail: mailto:k1ttt@arrl.net
web: http://wiki.k1ttt.net
AR-Cluster node: 145.69MHz or telnet://k1ttt.net
-----Original Message-----
From: Matrin Sole [mailto:hs0zed@csloxinfo.com]
Sent: Saturday, January 05, 2013 13:05
To: 'Towertalk'
Subject: [TowerTalk] Help with rotor valuation, Telrex
I have a large rotator that I am trying to find information on and some idea
as to value. Since it is really too big for anything I might ever have I
will likely dispose of it if I can figure out a reasonable value. Weighs
about 40kG so unless you live in Thailand I don't think this is for you.
It is a Telrex A3695RISX, that's what it says on the model number label.
Weighs about 40kG, large 1/3 HP Doerr motor driving a 3.5 inch output shaft
by way of two worm drive gearboxes and a 1 inch wide chain. Direction
information is from a General Electric Selsyn coupled to the drive shaft by
a small chain. The whole thing is mounted on an 18 inch by 10 inch steel
plate.
Anybody know anything about these, have any info, or care to offer an
estimate as to likely value?
Thanks
Martin, HS0ZED
_______________________________________________
_______________________________________________
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 121, Issue 11
******************************************
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|