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Tower bolts

Subject: Tower bolts
From: K7LXC@aol.com (K7LXC@aol.com)
Date: Mon May 13 12:18:34 1996
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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