80 mtrs and touchlamps
n0dh at comtch.iea.com
n0dh at comtch.iea.com
Tue May 14 16:20:32 EDT 1996
bbarr at charlotte.infi.net (WILLIAM L BARR) asked:
>Just wondering if I have the only touchcontrol lamps that come on and off
>while I use 80 mtrs and sometimes 40 mtrs. Tnks de N4UAJ.
Nope you aint the only one! I had a very confused neighbor in Huntsville
Alabama who had that problem..Seems the touch lamps in his bedroom
would come on flashing at all hours of the night. For a while he
thought he had "poltergiest" ~8^). Then one day I went over and
placed some "magic iron rings" (torroids) on his light cords
and the poltergeists gave up the ghost (pun intended !).........
If you own the lamp the problem is much easier to fix. Either disconnect
the touch module and put in a conventional switch or buy the XYL a
new (non touch) lamp and put the old one in the next garage sale.
>From biss at epg.nist.gov (Robert Biss) Tue May 14 11:46:18 1996
From: biss at epg.nist.gov (Robert Biss) (Robert Biss)
Date: Tue, 14 May 1996 10:46:18 +0000
Subject: The first MARCONI HF MEMORIAL CONTEST
Message-ID: <Q1989CBB at washer>
Are you sure that you want to do this on this particular weekend!!!!
It is only the weekend of the single most popular event in the United
States. This is FIELD DAY WEEKEND!!!!!!
Maybe you want to eliminate the U.S. Competition....
Maybe since this is the 1st of an annual event, you would reconsider what
weekend you really want to use.
It is probably an oversight on someone's part by not looking at a CONTEST
73 bob K3ZNV
>From sawyers at cacd.rockwell.com (sawyers) Tue May 14 14:45:11 1996
From: sawyers at cacd.rockwell.com (sawyers) (sawyers)
Date: Tue, 14 May 96 07:45:11 cst
Subject: Re: Tower bolts
Message-ID: <9604148320.AA832089102 at ccmgw1.cacd.rockwell.com>
It is not really case of failure as much as it is exceeding the limiting
stresses allowed in various applicable standards for different parts of the
design. Kind of like the weakest link in a chain theory.
In the case of Rohn 25 I think the column strength of the legs is the first
de n0yvy steve
______________________________ Reply Separator _________________________________
Subject: Re: Tower bolts
Author: Pete Smith <n4zr at contesting.com> at ccmgw1
Date: 5/13/96 1:24 PM
At 11:16 AM 5/13/96 cst, you wrote:
>Actually the tower leg bolts take both the tension and the compression
>forces on the joint as shear stresses in the bolts. for the Rohn 25 / 45 /
>55 series of towers and the HBX as well.
>The joint design is rather sensitive. In fact I was trying to increase the
>load on one of our Rohn 45 towers, and the Rohn data didn't seem to jive
>with what I was calculating, so I called the factory and talked to one of
>their engineers. He said in the case of the 45 series, the factory bolts in
>the joint were the limiting factor on compressive load. With the closely
>following limit being the bearing stress on the bolt holes in the tube.
>I think they went to fine thread to get a larger root diameter on the bolt
>to get the shear load up on all of the towers.
>I concur with several of the remarks on this thread: use grade 5 fine
>thread hot dipped galvanized fine thread bolts to get maximum strength from
>your tower sections. Also get them from a reputable vendor as foreign bolts
>have been having some quality control problems in the past. US bolts grades
>can be identified by looking at the head. There should be some radial lines
>on the head and an emblem of the bolt manufacturer.
Interesting ... I just learned something. Did the factory engineer indicate
whether the same "failure tree" would hold true with Rohn 25? I had tended
to assume that Rohn 25 legs would buckle under compression before you would
shear the bolts, and that either event would take a huge wind load as
compared to the more usual failures, which as I understand typically involve
Pete Smith N4ZR (n4zr at contesting.com)
>From hwardsil at wolfenet.com (Ward Silver) Tue May 14 17:00:11 1996
From: hwardsil at wolfenet.com (Ward Silver) (Ward Silver)
Date: Tue, 14 May 1996 09:00:11 -0700 (PDT)
Subject: 80 mtrs and touchlamps
Message-ID: <Pine.OSF.3.93.960514085808.6346B-100000 at gonzo.wolfenet.com>
On Tue, 14 May 1996 n0dh at comtch.iea.com wrote:
> If you own the lamp the problem is much easier to fix. Either disconnect
> the touch module and put in a conventional switch or buy the XYL a
> new (non touch) lamp and put the old one in the next garage sale.
I have a better solution...let's set up a foundation to BUY the damn
things from our neighbors. Then have a booth at all the hamfests where,
for a buck or two, you get to smash/shoot/stomp/defile the suckers. The
money raised goes to buying more touch lamps. I bet there's be LOTS of
guys that would happily pay...
73, Ward N0AX
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