Recently, I purchased a used A3S and am now about ready to put
it together and stick it up in the air. I would like to use
something other than the 8 turns of coax that is recommended by
Cushcraft. I spoke to them yesterday and they advised me that
it is ok to use a beam balun. I have found a couple of types
listed in the catalogs but wondered what baluns others had used
for this application. I don't necessarily need to go to a 1.5kw
model but will run up to about 800w from time to time. Any and
all ideas appreciated.
Thanks,
73 Wayne KC5DVT ehayes@vnet.ibm.com
>From sgemeny@access.digex.net (Steve Gemeny) Thu Jul 11 15:20:34 1996
From: sgemeny@access.digex.net (Steve Gemeny) (Steve Gemeny)
Subject: More Tower Help!
Message-ID: <Pine.SUN.3.94.960711100125.25768A-100000@access2.digex.net>
On Thu, 11 Jul 1996, Michael Tope wrote:
> Anyway, my question is rather simple - should I use a wooden form for the
> base? And if so, should I remove the form immediately after pouring the
> cement?
>
> Thanks in Advance!
>
> Mike, AD4VH
>
Nice choice Mike... I just finished the first 34' of my 40' Rohn 25.
Here is what I did. (I guess I'll hear about all my sins now)
1) Made a form for the top 6" that is to be above ground.
(A nice touch is include a beveled edge inside the form so the final ROCK
will look nice sitting above ground)
2) Dug the hole 4'+ deep by 18' square.
3) Positioned the frame with the top level and the side square to the
house (I am house bracketed at 14' and 24').
4) Filled the bottom of the hole with enough gravel to bring the mating
part of the short base above concrete (at least 8" of gravel to allow for
drainage from within the legs)
5) positioned and plummed the short base ATTACHED to the first section.
6) Poured the concrete (about 6 cubic feet 10 1/2 bags)
7) CROWN THE TOP!!! (for drainage)
8) after about 8-12 hours removed the form (concrete is still green but
quite firm... you know... SIGNING TIME)
Don't forget to water your concrete a few times a day for the first few
days to promote CURING not drying and allow a few days (a week is better)
to develop strength.
Good luck,
Steve AA3NM
Gaithersburg, MD
>From floydjr@Interpath.com (Jimmy R. Floyd) Thu Jul 11 13:50:58 1996
From: floydjr@Interpath.com (Jimmy R. Floyd) (Jimmy R. Floyd)
Subject: IARU Scores
Message-ID: <2.2.16.19960711125058.235f1d02@interpath.com>
I will be compiling the IARU scores for this weekends contest. Please
post them on the 3830 reflector or to me directly. DO NOT POST THEM ON
THIS REFLECTOR!
I am not sure exactly how I will format these scores yet. Please just
send me the summary of your contest program. I may be wrong but I do
not believe there are any single band classes or unassisted or assisted
class divisions. If they are PLEASE make sure you put that in your
summary. You cannot believe that 50% of my work comes from just moving
people around after they submit a score. Make sure that when you send
the orginal posting you put on it exactly and fully the class you want
to be put in.
Also I want to make this request again as I have for all contests. The
scores I do are NOT OFFICIAL!!!!! They are just something to give people
some idea where they placed. I can make mistakes just like anyone else
and please understand that is all they are. Just send me a correction
and I will be glad to make it.
My other request is to save you some problems. DO NOT SEND ME ANY LOGS
or attached files. I did receieve several FD logs. You need to send all
your logs to who ever sponsored the contest. Also if you send attached
files I have to get out of my mailer and then back to do those scores.
I usually do not do that. My feelings are if you do not have the time
to type them in or copy and paste that little file to an email I do not
have time to add your scores.
I know most of you have heard this before but at the rate new hams are
coming on Internet and all I feel it is worth the bandwidth to say this
all again. I will do it again before CQWW next year in Oct. Good luck to
everyone in IARU and hope to work some all of you.
73's Jim
**********************************************************
* Jimmy R. Floyd (Jim) Thomasville, NC *
* *
* Amateur Call: >> WA4ZXA << *
* Packet Node: >> N4ZC << *
* Internet Address: >> floydjr@interpath.com << *
**********************************************************
>From sawyers@cacd.rockwell.com (sawyers) Thu Jul 11 17:23:41 1996
From: sawyers@cacd.rockwell.com (sawyers) (sawyers)
Subject: More Tower Help!
Message-ID: <9606118370.AA837098691@ccmgw1.cacd.rockwell.com>
Burying a section of tower in concrete is not the Rohn recommended method.
Having said that, here is how I go about it.
Asuming you don't have cave in problems and that 42 inches is below frost
line in your area, I would dig a 2 foot square hole 4 feet deep. It is
better to have the concrete bearing against virgin undisturbed soil, than
forming it down and then back filling. Keep the sides straight down. Make
sure you don't get lazy and let them slope into the bottom.
Make a frame for the top out of 2x4's anywhere from 18 to 24 inches square.
Have the form extend out beyond the hole for support. Then put 6 inches of
gravel or small loose stone in the bottom of the hole and wiggle the bottom
section down into this gravel. You want to keep the bottom of the legs open
so they drain. The 2x4's will keep the top of the cement above ground
level. If you are going to house bracket this tower, something I highly
recommend, then assemble the tower all the way to the house bracket (using
ladders and the roof, not the tower, for support) and complete the house
bracket installation and fasten the tower to it.
Coat the tower with roofing tar from a point 6" above where the top surface
of the concrete will be, to a point 12" below the top surface of the
concrete. Roofing tar has fiber in it so it will give a good coating so you
won't get surface corrosion at the top of the concrete. Corrosion at this
point is really the reason for using the Rohn concrete tower legs - they
are heavier and provide more corrosion allowance than the thin tower legs.
I have seen lots of these types of installs that completely rust off at the
top of the concrete and are hanging by the house bracket.
You are better off to order the concrete form a concrete plant and have it
delivered. There are different grades of concrete. Typical foundation grade
is a 2500 to 3000 psi mix. I use 4000 psi concrete it is sometimes called a
7 bag mix (7 bags of cement per cubic yard). Make sure they know that this
is for outside exposure and ask for the "air entrainment" type of mix. It
has a special additive that keeps tiny air bubbles in the cement. You won't
be able to see them. The air entrained concrete resists cracking and
surface spalling better in freeze/thaw environments.
Make sure tower is staight up. Pour in about a foot of concrete. Make sure
tower is staight again. Pour in the next foot of concrete and make sure the
tower is straight up. Pour in the rest of the concrete. Finish the concrete
inside the form to have a slight (1/4" to 1/2" dome or crown so water will
run off. Make sure tower is straight up one last time.
After concrete sets up for about 6 to 8 hours, take an old rug or a couple
of layers of rags and lay on the concrete. Wet this down two to four times
a day to help the concrete cure. Do this for a week before you set up the
rest of the tower.
Good luck
de n0yvy steve
Disclaimer: I and my company agree on at least one thing: My opinions are
my own.
______________________________ Reply Separator _________________________________
Subject: More Tower Help!
Author: mtope@iu.net (Michael Tope) at ccmgw1
Hurricane Bertha willing (she appears to be!), I will be breaking ground on
my first tower in the coming days. Not wanting to bite off more than I can
chew, I will be putting up a rather small one (KC8MK please no off-color
comments!), 26' of Rohn 25G (3 sections with 4' under the ground). This will
serve as a home for VHF antennas, and my old Cushcraft A3 until such time
that I am ready for some real metal.
Anyway, my question is rather simple - should I use a wooden form for the
base? And if so, should I remove the form immediately after pouring the cement?
Thanks in Advance!
Mike, AD4VH
_______________________________________________________________________________
Michael Tope, AD4VH (ex KD8NS)
200 Easy Street
Melbourne, FL 32934
Phone: (407) 259-7494
Eail: mtope@iu.net
_______________________________________________________________________________
"It is the empty space inside the vessel that makes it useful" - Lao Tzu
>From gswanson@arrl.org (Swanson, Glenn, KB1GW) Thu Jul 11 17:26:00 1996
From: gswanson@arrl.org (Swanson, Glenn, KB1GW) (Swanson, Glenn, KB1GW)
Subject: IARU HQ Stations: From 1995
Message-ID: <m0ueNg8-000f4ZC@mgate.arrl.org>
Per the Feb. 1996 issue of * QST * -- page 112:
** THESE WERE FROM LAST YEARS CONTEST **
(But many will be the same this year, I believe. But, hey,
this is only my opinion. Reality may be different! HI)
-- ALL ARE SUBJECT TO CHANGE, I'D SAY --
In any event (pun intended), here we go:
HG95HQ (Guess it might me HG96HQ this year, eh?) = HA
OM5HQ (Might be OM6HQ this year, no?) = OM
EM5HQ (see above) = Ukraine
[Above could even be: UR-UZ, EM, EN, EO or US this year.]
YR0A = YO
DA0HQ = DL
S50HQ = S5
SP0HQ = SP
W1AW ("ARRL") = W
LZ7A = LZ
ER7A = (Moldova) [ER, RO , UO]
YU0HQ = YU
IY2ARI = I
SK3HQ = SM
LT4E = LU
GB5HQ (GB6HQ this year??) = G
8J3HXQ = JA
4V100RC = HH
LX0RL = LX
LY1RMD = LY
XJ7RAC = VE
HB9A = HB
Z30RSM = Z3 (Macedonia)
Confused?
Me too! HI ;-)
Work everything you can--worry later, I guess!
* Helpful: The "ARRL DXCC Countries List" has a real handy
"Allocation of International Call Sign Series" cross-reference
in the back it. Like: "IAA-IZZ Italy" and "OAA-OCZ Peru" etc.
73, Glenn, KB1GW
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