In a message dated 96-05-13 10:23:18 EDT, you write:
>Am I missing something in all this hubbub? With the downforce from three
>sets of guys, plus the weight of the tower, rotator and antennas, I can't
>see that there's a significant risk that a tower section will shear even a
>hardware-store bolt and pull out of the next section down. Obviously, it's
>good practice to use decent bolts, and make sure they're fairly tight, but
>going to specialty fasteners strikes me as unnecessary overkill.
>
Hi, Pete --
Thanks for your comments. Not being an engineer myself, I'm not
qualified to provide insight into manufacturers specs. I have found, though,
in my tower working experience that the prime directive is to "do what the
manufacturer says". Sometimes there doesn't seem to be a real obvious reason
for some of those things. But I'll guarantee you one thing -- it you follow
the manufacturer's specs, you'll never get yourself into trouble. The
reverse is also true.
73, Steve K7LXC
TOWER TECH -- professional tower supplies and services for amateurs
>From publinet@indi.it (Eliseo Chiarucci) Mon May 13 16:35:41 1996
From: publinet@indi.it (Eliseo Chiarucci) (Eliseo Chiarucci)
Subject: The first MARCONI HF MEMORIAL CONTEST
Message-ID: <199605131535.RAA00565@indi1.indi.it>
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The First MARCONI MEMORIAL CONTEST HF
1) Aim: The MARCONI MEMORIAL CONTEST HF commemorates the
II Century of RADIO and its father: GUGLIELMO MARCONI. It's a
world-wide competition: everybody can work everybody, only CW.
2) Date and time: Every IV full week-end of June from 1400 Utc
Saturday till 1400 Utc Sunday. In 1996 it will be on
22-23 June.
3) Classes:
1)Single Operator
2)Multi Operator.
Subclasses of class 1:
L) Low power (max 100W out)
Q) Qrp (max 5 watts out).
The operators L and Q in the class 1 will be marked and
awarded.
4) Bands and mode: Only CW, 10m thru 160m (except Warc bands)
are allowed according to IARU Band Plans. Band can be changed
only after 10 minutes you have been on it. The 10 minutes'
count starts from the first QSO made on that band.
5) Exchange: The station send RST + a serial number from 001.
6) Qso/Points: Each verificable QSO count 1 Point.
7) Multipliers: All DXCC countries count 1 multiplier.The same
multiplier can be counted once a band.
8) Final Score: The sum of Qso/Points from all bands multiplied
by the sum of multipliers from all bands.
9)Logs and summary sheet: separate standard logs are necessary
for each band. A summary sheet is required showing all the
scoring details on each band, class of entry, power, name,
callsign, full address of the applicant, callsign of the
operators and a signed declaration. Computerized logs on
diskette are welcome only in ASCII format. You can apply for
the free software to the Contest Manager: send a formatted
1.44 Mb diskette with SAE and two IRCs for return postage. Logs
must be mailed within 30 days from the end of the contest and
addressed to: ARI sez.di Fano POBox 35 61032 FANO (PS) Italy.
Please enclose your station description and your comments. A
picture will be much appreciated.
10) Penalties and disqualification: Penalties and disqualifi-
cation will be applied for violation of the contest rules.
Each decision of the Contest Committee will be final.
11) Award: A plaque with certificate will be awarded to the
No.1 top scoring station in each class and subclass. A
certificate will be awarded to No.2,3,4,5 top scoring in each
class as well as to the No.1 top scoring stations in each
country in each class and subclass.
The Committee will send to the No.1 top scoring of single
operator (if it is no member) the "MARCONISTA" award of the
MARCONI CLUB of LOANO.
IL PRESIDENTE SEZIONE A.R.I. FANO
LUCIANO NUCCI
IK6QQK
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>From U9556982@Queens-Belfast.AC.UK (Gerard Lynch - GI0RTN) Mon May 13
>21:32:56 1996
From: U9556982@Queens-Belfast.AC.UK (Gerard Lynch - GI0RTN) (Gerard Lynch -
GI0RTN)
Subject: Magnetic Loops
Message-ID: <9605131532.AA06604@ash20.causeway.qub.ac.uk>
I'm thinking of getting a magnetic loop for the low bands as I
simply do not have room for anything else and I would appreciate any
comments or advice people can give me on them.
--------------------------------------------------------------------
Gerard Lynch
u9556982@qub.ac.uk +44 1232 755818 GI0RTN
Belfast, N.Ireland
Need GI on WARC bands???????
Call me on either 10.101 or 10.115MHz CW - most evenings after 2200 UTC!
'Nothing is real' - John Lennon
'A woman is just a woman - but a good cigar is a smoke!' - WC Field
>From U9556982@Queens-Belfast.AC.UK (Gerard Lynch - GI0RTN) Mon May 13
>21:31:01 1996
From: U9556982@Queens-Belfast.AC.UK (Gerard Lynch - GI0RTN) (Gerard Lynch -
GI0RTN)
Subject: Oh Boy! do I love and hate Contests sometimes!
Message-ID: <9605131535.AA06626@ash20.causeway.qub.ac.uk>
I'm inclined to agree with Matt about limiting the smaller contests
a bit in bandwidth - the problem really comes with 40m however.
With low solar activity 40m really is the bread and butter band,
especially with the smaller tests with mainly EU-participants. I
find it really difficult to see how you can cramp contests anymore
that they already are on 40.
Limited QRGs are fine for other bands but 40 will remain a disater
area until we get an extension - 100kHz really isn't enough.
73 de Gerard
--------------------------------------------------------------------
Gerard Lynch
u9556982@qub.ac.uk +44 1232 755818 GI0RTN
Belfast, N.Ireland
Need GI on WARC bands???????
Call me on either 10.101 or 10.115MHz CW - most evenings after 2200 UTC!
'Nothing is real' - John Lennon
'A woman is just a woman - but a good cigar is a smoke!' - WC Field
>From k7fr@ncw.net (Gary Nieborsky) Mon May 13 17:01:56 1996
From: k7fr@ncw.net (Gary Nieborsky) (Gary Nieborsky)
Subject: Amp Parts
Message-ID: <199605131601.JAA07311@bing.ncw.net>
Thanks for all the info on my "Building an Amp" post a ways back. This
project has put some of the fun back into going to hamfests. Am piecing
together a 4cx1600 amp.
Next question:
I stumbled across a couple of Jennings vacuum variable caps (50-1500, 5kV)
that were alledgedly new. Guy wanted $50 each. The price was probably
ridiculously low since I didn't snatch them up. The question I have is
this: are Jennings worth the price? 5kV too low, should I shoot for the 10
or 15kV models?
Direct response please.
73 Gary K7FR
Antenna Farms
"I don't live in the middle of nowhere, but I can see it from the top of my
tower."
>From sawyers@cacd.rockwell.com (sawyers) Mon May 13 18:16:55 1996
From: sawyers@cacd.rockwell.com (sawyers) (sawyers)
Subject: Tower bolts
Message-ID: <9604138320.AA832004314@ccmgw1.cacd.rockwell.com>
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.
Grade 2 will not have any radial lines
Grade 5 will have three equally spaced radial lines
Grade 8 will have six equally spaced radial lines
Basically count the lines and add 2.
Some guys have been supstituting 17-4Ph stainless steel bolts with good
luck, but not the garden variety 304 stainless. I don't have the material
specs here to do an adequate comparison at this time as I am busy getting
ready for Dayton. Will be in Flea Spaces 1564/65.
de n0yvy steve
______________________________ Reply Separator _________________________________
Subject: Tower bolts
Author: n4zr@contesting.com (Pete Smith) at ccmgw1
Am I missing something in all this hubbub? With the downforce from three
sets of guys, plus the weight of the tower, rotator and antennas, I can't
see that there's a significant risk that a tower section will shear even a
hardware-store bolt and pull out of the next section down. Obviously, it's
good practice to use decent bolts, and make sure they're fairly tight, but
going to specialty fasteners strikes me as unnecessary overkill.
73,
Pete Smith N4ZR (n4zr@contesting.com)
>From w6go@netcom.com (Jay O'Brien - W6GO) Mon May 13 17:27:14 1996
From: w6go@netcom.com (Jay O'Brien - W6GO) (Jay O'Brien - W6GO)
Subject: Amplifier bandwidth
Message-ID: <199605131627.JAA19544@netcom18.netcom.com>
If KB8QU's QRO Technologies HF-2500DX amplifier only takes up ten percent
of the extra bandwidth on twenty meters that it took up here on the
reflector (4173 lines were reported by my mail reader) I certainly would
never want to get within a mile of the amplifier.
Preposterous.
Jay
w6go@netcom.com
>From qrotec@bright.net (QRO Technologies, Inc.) Mon May 13 17:41:41 1996
From: qrotec@bright.net (QRO Technologies, Inc.) (QRO Technologies, Inc.)
Subject: Apology
Message-ID: <199605131641.MAA15021@brutus.bright.net>
Hey Guys,
Sorry for the HF-2500DX announcement. That message was sent in error. It was
intended for another receiptant. Please rest assured it will not happen
again. I have no intention to use this users group as an advertising medium.
So, relax.
Best 73's
Ray W. Connin KB8VU
QRO Technologies, Inc.
>From zettel@homer.libby.org (Steve Zettel) Mon May 13 18:17:34 1996
From: zettel@homer.libby.org (Steve Zettel) (Steve Zettel)
Subject: Dropped off list
Message-ID: <v02140b02adbd1da693af@[192.0.2.1]>
To those folks that attempted to send me any e-mail from the reflector, I'm
not ignoring you. My home address was dropped of the list for some reason
and didn't receive anything for the last three to four days. Thanks to Pete
Smith for alerting me that his attempts to contact me were bouncing.
Evidently, my work address on the reflector is/was still good, but I don't
originate everything I send from there. Sorry for any inconvenience.
Steve Zettel KJ7CH zettel@libby.org
Libby, MT USA steve.m.zettel@usace.army.mil
Take a tour of NW Montana at: http://www.libby.org
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