Hey Leon,
You need to change the SUBJECT of the e-mail so we know what you are
asking about and trim the message down to cover the subject at
hand! This will help tons!!!
Dino - K6RIX
At 10:54 AM 5/16/2007, you wrote:
>----- Original Message -----
>From: <towertalk-request@contesting.com>
>To: <towertalk@contesting.com>
>Sent: Wednesday, May 16, 2007 9:00 AM
>Subject: TowerTalk Digest, Vol 53, Issue 62
>
>
> > 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: the elusive 1db (Wes Attaway (N5WA))
> > 2. Re: inspection list (jacobsen_5@msn.com)
> > 3. Re: What relay do Ameritron and Array Solutions (jeremy-ca)
> > 4. Dayton Hamvention Amateur Radio & the Law Forum (Jim OConnell)
> > 5. Re: Balun on LPDA (Bill Turner)
> > 6. Re: Got a tower/antenna in a CC&R subdivision? (Bill Turner)
> >
> >
> > ----------------------------------------------------------------------
> >
> > Message: 1
> > Date: Tue, 15 May 2007 21:17:37 -0500
> > From: "Wes Attaway (N5WA)" <wesattaway@bellsouth.net>
> > Subject: Re: [TowerTalk] the elusive 1db
> > To: "'Bob Nielsen'" <nielsen@oz.net>, "'TowerTalk List'"
> > <towertalk@contesting.com>
> > Message-ID: <003b01c79760$5fa93dd0$2801a8c0@office2>
> > Content-Type: text/plain; charset="US-ASCII"
> >
> > That is a real interesting observation about that dish. I had
> > some experience at Michigan State back in 1962-63 writing some
> > Fortran programs and using IBM punched cards. I never saw the
> > computer. In fact, I didn't really know much about how the
> > computer worked. I just wrote some code, punched the cards, and
> > put them into a steel drawer. The next day I would come back and
> > see if the white-coated computer priests had given me a printout.
> > It was touch and go, but finally I got some actual results.
> >
> > My guess is that someone actually did the math for the dish and
> > wrote a program and ran it on a mainframe and came up with the
> > design. It could be done .... it just took a little longer back
> > then. But even then the computer was a lot faster than a slide
> > rule, and a whole lot more accurate. Slide rules were great, but
> > you were lucky to get within 10 per cent if there were very many
> > calculations to make.
> >
> > -----Original Message-----
> > From: towertalk-bounces@contesting.com
> > [mailto:towertalk-bounces@contesting.com] On Behalf Of Bob
> > Nielsen
> > Sent: Tuesday, May 15, 2007 8:25 PM
> > To: TowerTalk List
> > Subject: Re: [TowerTalk] the elusive 1db
> >
> > On May 15, 2007, at 3:02 PM, Pat Barthelow wrote:
> >
> > >
> > >
> > >
> > > That elusive DB just reared it head at Jamesburg. We
> > discovered
> > > that our
> > > dish has neither parabolas, or hyperbolas as part of normal
> > Cassegrain
> > > surfaces. Mike Brenner, our laser metrologist just determined
> > that
> > > the
> > > dish, built by Philco Ford in Late 60s, probably designed in
> > early
> > > 60s was a
> > > tweaked design that had reshaped both surfaces to gain only
> > about 1
> > > db more
> > > in the 63 dbi gain dish.
> > > I dont know why they went to all the trouble to do that to just
> > get
> > > one more
> > > DB to listen to Geosynchronous Satellites.
> > >
> > > But a more interesting question, in light of the fact that this
> > was
> > > WAY
> > > before the HP 35 was around , (;>) in fact in the REAL olden
> > days,
> > > Engineers used slide rules, and surveyors used 8 place trig and
> >
> > > Logarithm
> > > tables. Logsin A minus Logtan B plus...oops...
> > >
> > > Anyone here from that era who might know if such a dish
> > required the
> > > computation horsepower of a mainframe of the time, to design
> > and
> > > build?
> > > Say a bunch of Fortran Punch Cards and an IBM 360?
> > >
> >
> > Maybe a bunch of grunts wielding Friden or Marchant calculators?
> >
> > I worked at Douglas Aircraft for a brief time in 1957 before
> > going to
> > college. My job title was "technical computer" and I had a nice
> > but
> > noisy Friden mechanical calculator on my desk to use in
> > processing
> > flight test data for the Navy A4 jet (which I had read from 35 mm
> >
> > film, their being a camera in the cockpit pointed at the
> > instrument
> > panel). After I had been doing this for a few months, my boss
> > asked
> > me to prepare some punch cards with the raw data, as they wanted
> > to
> > see if they could get one of their few computers (which belonged
> > to
> > the payroll department) to process the data (which I had already
> > done
> > manually so they would have something to cross check against the
> >
> > computer output).
> >
> > 73 - Bob, N7XY
> > _______________________________________________
> >
> >
> >
> > _______________________________________________
> > TowerTalk mailing list
> > TowerTalk@contesting.com
> > http://lists.contesting.com/mailman/listinfo/towertalk
> >
> >
> >
> >
> > ------------------------------
> >
> > Message: 2
> > Date: Tue, 15 May 2007 21:23:11 -0500
> > From: <jacobsen_5@msn.com>
> > Subject: Re: [TowerTalk] inspection list
> > To: "towertalk" <TowerTalk@contesting.com>
> > Message-ID: <BAY111-DAV1521C27A683CAD8875588B23C0@phx.gbl>
> > Content-Type: text/plain; charset="iso-8859-1"
> >
> > Hi guys and gals..... again....... on Franks' Tower inspection
>list.............
> >
> >
> > For some reason, from time to time, when ever I include a web address in
>my e-mails, the link duplicates itself when it comes out thru the list.
>Haven't figured it out yet. Works sometimes, other times it dups.
> > Anyway, if your not clicking on the address contained in Franks, W3LPL
>original post on the tower inspection, check it out and delete all that is a
>dup at the end.........
> >
> > 73
> > Jake K9WN
> >
> > ------------------------------
> >
> > Message: 3
> > Date: Tue, 15 May 2007 23:18:24 -0400
> > From: "jeremy-ca" <km1h@jeremy.mv.com>
> > Subject: Re: [TowerTalk] What relay do Ameritron and Array Solutions
> > To: <towertalk@contesting.com>, "Jim Lux" <jimlux@earthlink.net>
> > Message-ID: <007f01c79768$df71f950$6500a8c0@KITTYMA123>
> > Content-Type: text/plain; format=flowed; charset="iso-8859-1";
> > reply-type=original
> >
> >
> > >
> > > The VNA might take the guesswork out of some of the measurements, but
> > > doesn't tell you much about how to change the design to make it
> > > "better". And for using "non-RF" components in RF applications
> > > (which is what most amateur market relay boxes are.. they are NOT
> > > clever stripline designs like DowKey uses) there's an awful lot of
> > > craft and art to the design, probably moreso than straightforward RF
> > > circuit design. (Unless someone's been out building HFSS models for
> > > relays).
> >
> >
> > The VNA is simply a tool. As with any tool it requires that the user have
>an
> > understanding of its abilities as well as his own.
> >
> > The DowKey is not a stripline design, it is a coaxial line section; big
> > difference.
> >
> > Commercial radio manufacturers have been using small open frame power
>relays
> > in RF use for over 60 years, nothing new there. Vacuum relays designed
>for
> > switching HV made an easy transition to RF.
> >
> >
> > >
> > > The VNA just tells you "good", "bad", or "about the same"... but
> > > doesn't tell you "make the box 1/4" taller so the parasitic C is
> > > less".. that comes from either mindnumbing analysis (probably a waste
> > > of time) or good old empiricism (try a bunch of different ideas, and
> > > see what works).
> >
> >
> > Ive never had parasitic C problems at HF in a straight 50-75 Ohm layout.
> > Amplifiers and even antenna tuners are another story. A lot of my work
> > resume included millimeter wave
> > circuitry up to and beyond 60 gHz; now THAT stuff is tricky! But you can
>do
> > a lot with
> > RF absorbent material at microwaves and above
> >
> > After youve been around the circle a few times the old gut feeling is
> > often the key to success if I may borrow an anology from my younger
> > circle track racing days.
> >
> >
> > >
> > > And, a lot of what goes into amateur products (or pro products for
> > > that matter) is non-RF related.. manufacturing cost, durability,
> > > shipping, etc. all factor into component choices. I've seen
> > > products (not in the ham market, and not RF related) that were
> > > originally designed around the ready availability of a particular
> > > surplus component. Then, when the surplus supply ran out, the mfr
> > > had to go out and have custom parts made to duplicate a long
> > > discontinued WW-II vintage part. That drove the Bill of Materials
> > > (BOM) cost through the roof... especially for replacement parts for
> > > the original widgets, and drove a completely new design.
> >
> > A lot of surplus parts from WW2 Ford and Willys built jeeps found their
> > way into Kaiser civilian models.
> > Heathkit started in business with WW2 surplus parts.
> > I got my SWLing and later ham start with surplus from Radio Row in NYC
> > back in the 50's.
> >
> >
> > >
> > >>When KQ2M operated my station 1987-95, I designed and built all of the
> > >>elaborate stack switching and elevation steering for a 4 stack of yagis
>on
> > >>20, 15 & 10 as well as the pattern switching for 160 & 80 antennas.
>Specs
> > >>were so tight that amp tuning never changed even when several relays and
> > >>networks were in the signal path. Performance was obvious in the contest
> > >>scores.
> > >
> > > Just out of curiosity.. did those relay boxes work that well in the
> > > initial design, or were there any design changes? Do you think you
> > > might have just "gotten lucky" in the design and component selection
> > > in the 80s?
> > >
> > > I've been casually measuring a variety of off the shelf relays over
> > > the past year or so, and there's huge variations between seemingly
> > > identical relay designs from multiple manufacturers.
> > >
> >
> > I had already characterized numerous relays and had settled on new DPDT PB
> > with dust cover 24VDC
> > surplus units from All Electronics. They had more than adequate return
>loss
> > and isolation at 10M
> > and below. Plus they were cheap, I think $2 each!
> > And since they would be mounted in gutted CATV hardline boxes I liked the
> > dust cover to
> > minimize condensation here in NH.
> > Since elevation steering was part of the array the VNA was a key in
> > determining the
> > built in phase delay through the various selections. With that determined
> > it was then easy to
> > cut the phasing cables to exactly what was needed. Since I was using all
>75
> > Ohm hard and soft line it
> > was extremely advantageous that the company I was working for had the 75
>Ohm
> > option kit for the HP VNA.
> >
> > In the air performance was just as expected, no luck involved I hope! I
> > could barely see the
> > difference in grid current at any stack setting. This kept the LK780 happy
> > (a very low production
> > 2 x 3CX800A7 amp from Amp Supply) and the LK500 was always idiot proof.
> > (KQ2M was one of the
> > originators of the SO2R concept).
> > Remember that I didnt operate those contests and the first design goal
>was
> > to NOT be woken up at 3AM to fix a
> > sleepy operator induced problem!
> >
> > When Bob got married and bought his own place in SW CT I dismantled most
>of
> > the hardware.
> > These days my interests are primarily 80/160 and then 6M and above; way
> > above.
> >
> > Carl
> > KM1H
> >
> >
> > > Jim, W6RMK
> > >
> > >
> > > _______________________________________________
> > >
> > >
> > >
> > > _______________________________________________
> > > TowerTalk mailing list
> > > TowerTalk@contesting.com
> > > http://lists.contesting.com/mailman/listinfo/towertalk
> >
> >
> >
> > ------------------------------
> >
> > Message: 4
> > Date: Wed, 16 May 2007 08:11:21 -0500
> > From: Jim OConnell <w9wu@arrl.net>
> > Subject: [TowerTalk] Dayton Hamvention Amateur Radio & the Law Forum
> > To: towertalk@contesting.com
> > Message-ID: <464B02F9.5040106@arrl.net>
> > Content-Type: text/plain; charset=us-ascii; format=flowed
> >
> > Hamvention Amateur Radio and the Law Forum,
> > Friday, May 18, 2007 Room 3, 12:45 p.m. - 2:15 p.m. Amateur Radio and
> > the Law: Getting It Up and Keeping It Up
> >
> > Moderator: Jim O'Connell W9WU, ARRL Volunteer Counsel
> > Speakers: Fred Hopengarten,K1VR; Author,"Antenna Zoning for the Radio
> > Amateur".
> > Brennan T. Price, N4QX, ARRL Volunteer Counsel
> > Paula Uscian, K9IR, ARRL, Volunteer Counsel
> > Tim Ellam, VE6SH, IARU Vice President;
> > A discussion by Amateur Radio Attorneys on legal issues of interest to
> > hams: How to avoid restrictive covenants and cc&r's, present your case
> > for a tower permit, info on the latest court rulings on RFI, PRB-1 and
> > towers. Updates on the ARRL's Legal Defense and Assistance Committee.
> >
> > 73, Jim O'Connell, W9WU
> >
> >
> >
> >
> > ------------------------------
> >
> > Message: 5
> > Date: Wed, 16 May 2007 08:33:49 -0700
> > From: Bill Turner <dezrat@copper.net>
> > Subject: Re: [TowerTalk] Balun on LPDA
> > To: <towertalk@contesting.com>
> > Message-ID: <gt8m431so2qihimuf1veecvatsdpa96u3q@4ax.com>
> > Content-Type: text/plain; charset=us-ascii
> >
> > ORIGINAL MESSAGE:
> >
> > On Sat, 28 Apr 2007 00:07:22 +0200, "Peter Voelpel"
> > <df3kv@t-online.de> wrote:
> >
> > >If you feed with open wire you have to convert to unbalanced 50 ohms at
>the
> > >other end, so using a balun at the feedpoint is preferable.
> >
> > ------------ REPLY FOLLOWS ------------
> >
> > How about using balanced line all the way with a balanced tuner at the
> > shack end?
> >
> > It could be tricky to keep the balanced line from touching the mast or
> > any part of the tower as the antenna rotates. Some careful planning
> > would be needed there.
> >
> > Bill W6WRT
> >
> >
> > ------------------------------
> >
> > Message: 6
> > Date: Wed, 16 May 2007 08:51:29 -0700
> > From: Bill Turner <dezrat@copper.net>
> > Subject: Re: [TowerTalk] Got a tower/antenna in a CC&R subdivision?
> > To: towertalk@contesting.com
> > Message-ID: <ov9m43prfre120top33pi0tceompfl807c@4ax.com>
> > Content-Type: text/plain; charset=us-ascii
> >
> > ORIGINAL MESSAGE:
> >
> > On Tue, 15 May 2007 17:57:51 -0700, "Tom Osborne" <w7why@verizon.net>
> > wrote:
> >
> > >
> > <snip>
> > I really like the government getting involved in my
> > >life, telling me what I can and can't do in my own house, inside or out.
> > >More govenment meddling is just what we need in this country. 73
> > >Tom W7WHY
> >
> > ------------ REPLY FOLLOWS ------------
> >
> > I don't think the government is involved in HOAs and CC&Rs, are they?
> >
> > Bill W6WRT
> >
> >
> > ------------------------------
> >
> > _______________________________________________
> > TowerTalk mailing list
> > TowerTalk@contesting.com
> > http://lists.contesting.com/mailman/listinfo/towertalk
> >
> >
> > End of TowerTalk Digest, Vol 53, Issue 62
> > *****************************************
>
>_______________________________________________
>
>
>
>_______________________________________________
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>
>
>
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Dino - K6RIX
dino@k6rix.com
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