Antenna & Tower Recommendations

markg at markg at
Sun Apr 16 16:48:20 EDT 1995

  I have been reading for some time posting on this reflector concerning 
  contests, antennas, and station configuration and know this is a very 
  well informed group.  In an effort to work more than the top ten 
  stations in a contest and do some DXing in this low sun spot period 
  (work BS7H? I never even heard BS7H) I have made plans (translation: 
  finally gotten the wifes approval) to put up a tower on our small lot 
  (i.e. very difficult to put up any type of wire antenna even on 40M).
  I have put together a configuration based on performance, 
  survivablility, serviceability, and neighborhood friendlyness (i.e. 
  lowest height when cranked down). Since I will have to live with 
  whatever I decide to do I would very much appreciate any comparsions, 
  feedback, experience, or suggestions on the following:
  Tower: Tri-Ex LM-470 or US Tower HDX-572  @65' (local limit) 
  At 65': Force-12 Magnum 520/240 (5 element 20M, 2 element 40M)
  At 50' (using TIC ring rotor): Force-12 4BA  or DX Engineering LP17
      (for 10,12,15,17) (comparsions?)
  Would there be any big advantage to putting a 5-band ant. at 50' such
  as a 5BA or LP20 to get another 20M choice or would I just get 
  destructive interference?
  Please send responses directly so as not to clutter the reflector. If 
  enough interest I will post the results. Thanks and maybe you'll even 
  be able to hear me in the next contest.
  Mark  AB6WD
  markg at

>From David & Barbara Leeson <0005543629 at>  Mon Apr 17 00:00:00 1995
From: David & Barbara Leeson <0005543629 at> (David & Barbara Leeson)
Date: Sun, 16 Apr 95 18:00 EST
Subject: Rotators w/ shafts
Message-ID: <90950416230009/0005543629NA3EM at MCIMAIL.COM>

I've been fooling around calculating the torque capacity of keyed steel
shafts, using the information in Machinery's Handbook.  It appears that
even with the best hardened steel, it is not possible to design a keyed
1" diameter steel shaft that can carry 5000 in-lb torque with a heavy
shock load.  This could explain the disappointing results obtained with
HDR300 or Orion 2300/2800 rotators in many applications.

I was alerted to this by a letter from VE3AIA, who suggested flanged or
similar connection to the output gear of a rotator as a stronger way to
go.  It appears that a 1.5" or 2" shaft with the appropriate size key
(1/2") can carry the rotating torque specified by the rotator manufacturers,
but certainly not the much higher braking torque numbers I've seen in
various specifications.

It seems that the output gear of a high-performance rotator needs to be
connected directly to the mast (or better, to the mast torque shock
absorber), or through at least a 2" diameter hardened steel shaft with a
key made of the same material.  Unfortunately, most rotators made with
a direct connection between the output gear and the mast aren't made with
strong enough stuff, so the benefit isn't there.  Maybe TIC would consider
a ring rotator design to fit inside a standard tower section as a good way
to rotate a mast.

This information is in Machinery's Handbook, page 311 (shafts) and 2234
(keys and keyways).  I'd be interested in anyone else's calculations of
shaft torque in rotators.  I haven't had really satisfactory results from
either HDR300's (I have 4) or Orion 2300's (I have 2), and the major problems
seem to be working of the keys in the shafts resulting in excessive play.

Does anyone have experience with the new Yaesu HD rotator?  Geez, it only
takes 1/10 horsepower to get 6300 in-lb at 1 rpm, you'd think it could be
a snap.  Comments or ideas, anyone?

73 de Dave, W6QHS

>From kn5hose at (kn5hose)  Mon Apr 17 02:22:41 1995
From: kn5hose at (kn5hose) (kn5hose)
Date: Sun, 16 Apr 1995 19:22:41 -0600
Subject: cancelling prop info
Message-ID: <199504170122.TAA22660 at>

WHO ARE YOU????????????????????

>From kn5hose at (kn5hose)  Mon Apr 17 02:23:54 1995
From: kn5hose at (kn5hose) (kn5hose)
Date: Sun, 16 Apr 1995 19:23:54 -0600
Subject: More Sprint Thoughts
Message-ID: <199504170123.TAA22700 at>

Great idea, are you volunteering to collect logs and publish results??
de Hose KN5H .... ..

>From kn5hose at (kn5hose)  Mon Apr 17 02:28:51 1995
From: kn5hose at (kn5hose) (kn5hose)
Date: Sun, 16 Apr 1995 19:28:51 -0600
Subject: Complaint department
Message-ID: <199504170128.TAA22858 at>

Tree, how do we get the ARRL to do a more efficient job regarding contest
results?? I am very guilty of whining about the lack of log checking.
(I should beware.. my SS log dropped from 1352 to 1319,, of course it was
my fault). Let us know what if anything you heard about this traumatic
problem de Hose KN5H

>From Paul Knupke (CS)" <knupke at  Mon Apr 17 04:24:30 1995
From: Paul Knupke (CS)" <knupke at (Paul Knupke (CS))
Date: Sun, 16 Apr 1995 23:24:30 -0400 (EDT)
Subject: squINT
Message-ID: <Pine.SUN.3.91.950416231722.23794B at babbage>

squINT results for KR4YL:

Total time: 50 minutes
Total contacts: 5 (K1CC, K1VR, AA2IX, KM3T, and one I can't remember as 
the log is elsewhere.) 

Total multipliers: 4 (MA, CT, RI and NY) 

Operator: my youngest sister Karen.  (The first YL to operate KR4YL ever!)

Exchange: Karen, 13, Green, Florida

We S&P'ed the entire thing, as none her CQ's were returned.  

Conditions here in Florida were not very good, several folks we heard who 
Karen wanted to work were not workable with strong signals 1.5 to 2 KHz 
away.  Had lots of QRM from several Spanish speaking stations. 

It was the first time I have been able to get any of my three sisters in 
front of a radio (can't get them to talk to people they know on 2 
meters or 70cm.)   

I wish it was longer, just as Karen was getting into the swing of 
phonetics and proceedures it was over.  

The best operator I heard was Adam at K1CC.  

73 de KR4YL

* ======================================================================= *
> Paul Knupke, Jr. < * > University of South Florida Computer Engineering <
> knupke at    < * >      Fidonet 1:3603/61 or 1:377/61 <
> Tampa, FL * Amateur Radio Callsign KR4YL * Packet @WA1GUD.#TPA.FL.NOAM  <
* ======================================================================= *
        "We're only immortal for a limited time ..." -- Neil Peart

>From apontej at (Jose Aponte)  Mon Apr 17 04:37:06 1995
From: apontej at (Jose Aponte) (Jose Aponte)
Date: Sun, 16 Apr 1995 23:37:06 -0400 (EDT)
Subject: More Sprint Thoughts
Message-ID: <m0s0hcZ-00028mC at>

> Great idea, are you volunteering to collect logs and publish results??
> de Hose KN5H .... ..
>c disclosure either   but putting out there in a file server would ease 
the load of checking because anyone with a doubt & on the net could check it.
if it outs the work... I have been requesting the logs at least of the 
record holders... No Way Jose... not wiht an H ;-)   
Sorry John... put could not resist... to post on this...

write to cq-magazine at c/o john...

that way you can do the same with the arrl... I am not.


>From Jerry Sidorov" <jerry at  Sun Apr 16 19:12:04 1995
From: Jerry Sidorov" <jerry at (Jerry Sidorov)
Date: Sun, 16 Apr 95 22:12:04 +0400
Subject: Phone WPX 95 score
Message-ID: <AAqtLalyi0 at>

                       CQ WORLD WIDE WPX CONTEST  1995

      CALL: UA9AR                    COUNTRY: Asiatic Russia
      MODE: SSB                      CLASS: SO


      160        4       24     6.0          2
       80       23      126     5.5          6
       40       52      300     5.8         39
       20      305      885     2.9        173
       15      421     1263     3.0        187
       10        0        0     0.0          0
     Totals    805     2598     3.2        407   =>  1,057,386

All reports sent 59(9) unless otherwise noted.

Equipment Description:  Home-Brewed TRCVR 200W output,
                        Horizontal Delta on 160m,
                        4 Switched Slopers on 80m & 40m
                        W-E Phased Dipoles on 40m
                        3 el Yagi @ 60' on 20m
                        4 el wide spaced Yagi @ 60' on 15m

Club Affiliation: None

This is to certify that in this contest I have operated
my transmitter within the limitations of my license and have
observed fully the rules and regulations of the contest.



               Jerry Sidorov  UA9AR
               P/O Box 9411
               Chelyabinsk, 454080, Russia

        73,  Jerry  UA9AR.

>From David & Barbara Leeson <0005543629 at>  Mon Apr 17 07:39:00 1995
From: David & Barbara Leeson <0005543629 at> (David & Barbara Leeson)
Date: Mon, 17 Apr 95 01:39 EST
Subject: Contest Amps
Message-ID: <61950417063916/0005543629NA2EM at MCIMAIL.COM>

After last October's CQWW SSB at HC8A, Rich N6KT and I spent nearly the
whole 8-hour flight from Quito to Miami daydreaming about the perfect
contest DXpedition amplifier.  We scribbled down some specs, listed here
in a somewhat priority order.  Comments and suggestions are very welcome,
we just thought it would be interesting to other contesters...

Transportable, Easy-to-tune Contest Amplifiers per N6KT, W6QHS

>1200 watts output all bands with 100 w drive, good input match
6 bands, no WARC req'd
Output power, SWR metering
Built in transceiver band filters, output harmonic filters
Minimum weight (<35 lbs. per box, 2 max)
Ship with tubes in sockets - vibration isolate amplifier RF deck
Small size, tubes in horizontal position?
Shape similar to TS830/930/940
Separate power supply or removeable transformer for transport
LCD meters for travel shock, weight
Big blower(s), vacuum relays
Transmit-receive relays timed so no chance of hot switching
Single transformer incl. filaments, bias, taps for various line voltages
Auto adjustment for varying line voltage, or easy switch
Restart without delay (at least if has been running), or "battle short"
ALC (rather than fault) from all of Pout, Prev, Ig, Ip, plate RF voltage
Breakers, not fuses for mains
Preset scale you can write on easily (and erase)
Verniers?  Air caps for weight, can be fixed in field
RF output transformer for smaller capacitance on output side, lower Q?
Bleeders minimum dissipation (switch or relay off?)
Step start, electronic bias switching for minimum dissipation
Carrying case (canvas?)
Flat knobs for shipping size
Very safe, easily repaired HV connection if separate power supply 
Electrolytic caps ok
1 KV piv, 2.5A diodes for field replacement
MOV's in AC mains, easy to change AC connectors
Ground at power supply, diode at RF deck
Fold-out handles
Circuit diagram on bottom or inside of case for field repairs
Minimum different tools and fasteners req'd to service case, knobs, etc.
Top mounting available for antenna switches
Shaft out back for antenna switches, or switching voltage for relays?
3CX1200A7-D7 the best tube for all of this, or multiple 4CX350's?

Please direct comments directly to me, and I will summarize.

73 de Dave, W6QHS  554-3629 at

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