Need Help with Daiwa Rotor

zf8bs at twg.com zf8bs at twg.com
Thu Sep 1 15:06:16 EDT 1994


Does anybody here know anything about a Daiwa Rotor, Model MR-750E
or MR-750PE?  I can't tell which it is I have, though I know it is
one of them.  The control box I have is a Model CR-4P.  I'm trying 
to locate either an instruction sheet or an owners manual.  Can 
anybody help?  Thanks.
                                    Bruce Sawyer, AA6KX

>From modular!liddy!eric at cs.arizona.edu (Eric Gustafson)  Thu Sep  1 23:33:00 1994
From: modular!liddy!eric at cs.arizona.edu (Eric Gustafson) (Eric Gustafson)
Date: Thu, 1 Sep 94 15:33 MST
Subject: No subject
Message-ID: <m0qgKh0-00009bC at liddy>

To: arizona!paonline.com!bill.lumnitzer
CC: cq-contest at tgv.com
In-reply-to: <9409011303.0IC5G00 at paonline.com> (message from arizona!paonline.com!bill.lumnitzer on Thu,
	01 Sep 94 13:03:11 -0400 (EDT))
Subject: Re: I.C.E. TELNO


 >
 > Se> I like the way their low pass filter is built, but the coaxial
 > Se> lightning suppressor I bought was disappointing.  While their
 > Se> literature claims  the suppressor element is a heavy-duty ceramic unit,
 > Se> inside I found a little
 > Se> glass bulb about the size of an NE-2, with about 24 gauge leads.  I
 > Se> never bothered to install it, and should just send it back.
 >
 > Se> Scott  K9MA
 > Se> sellington at mail.ssec.wisc.edu
 >
 >The I.C.E lightning protectors use a shunt toroidal rf choke as the primary
 >protection; the arc-tube provides secondary protection. There is also a
 >shunt hv cap and a series resistor in the circuit.  I understand that most
 >if not all other brands use an arc-tube as the sole protection element and
 >that failures are commonplace.  I.C.E claims that out of 1000s sold, they
 >have never had a request for a replacement arc-tube.  Perhaps you should
 >discuss your concern with their engineer or read their tech note on the
 >subject before you decide not to use their protector.  The I.C.E factory
 >station uses these things and is purportedly operated in contests
 >right through the most severe lightning!
 >
 >73 de Bill, N6CQ/3  (n6cq at paonline.com)
 >


If these descriptions are true, then the probable difference (between I.C.E.
and PolyPhaser)is that the Polyphaser unit stands a chance (if properly
installed in a well engineered system) of protecting the equipment in the
shack from the consequences of a direct hit to the tower structure to which
the equipment is connected via feedline and the I.C.E. protector described
above probably won't.  PolyPhaser doesn't have a ham station to generate
anecdotes about but they do have a complete test facility capable of
simulating lightning bolt magnitude voltages and currents for testing their
devices.

The above statement is strictly opinion based on a large amount of
experience with mountaintop installations protected by PolyPhaser and other
suppressors.  I have no direct experience with the I.C.E. stuff but the NE-2
style gas tube with small round leads is inadequate in my opinion.  I have
pulled duplexers apart which were hit through inadequate protectors that
had coupling loops made of 3/8 inch wide solid copper strap (.032" thick)
folded flat against the top of the cans due to magnetic forces.  I'm sure
the same fault would have vaporized the NE-2 leads.  That leaves the choke
to dissipate the brunt of the current.  Unless this is a seriously large
torroid (possessing some magical properties not found in other inductors) I
don't see how this can protect the leads of the NE-2 style tube from
catastrophic damage.  How is this supposed to work?  The inductance
suddenly goes to zero due to core saturation during a fault?  If so, what
happens to the core material?  What happens to the core material when
transmitting 1.5 KW output on 160 M with a 3:1 or 5:1 SWR?  What is the
function of the shunt cap?  Are these suppressors limited to a particular
band?  Why would I tolerate a series resistance (I assume in series with
the center conductor) in my feedline unless I was feeding a MAXRAD dipole?

I'm sure there must be something I'm missing here.  Someone please post a
rational description of how the I.C.E. protector described above is
supposed to work.  What is its insertion loss when driving a 3:1 SWR (load
impedance low compared to line impedance?  Maybe we can all learn a bit of
magic.

73,  Eric  N7CL

------------------------------------------------------------------------------
Eric Gustafson  N7CL                  | The mountains are high and the Emperor
6730 S. Old Spanish Trail             | is far away.
Tucson, AZ 85747                      |
INTERNET: modular!eric at cs.arizona.edu | You can't work 'em
     CI$: 71750,2133		      | if you can't hear 'em.
------------------------------------------------------------------------------

>From p_casier at ub4b.eunet.be (Peter Casier)  Fri Sep  2 01:52:31 1994
From: p_casier at ub4b.eunet.be (Peter Casier) (Peter Casier)
Date: Fri, 2 Sep 1994 02:52:31 +0200
Subject: forget about the 10 min rule?
Message-ID: <199409020052.AA09356 at ub4b.eunet.be>

>Why all this fuss?  Why don't the "powers that be" eliminate this archaic
>carryover from the distant past?   I don't understand why this rule still 
>exists.  Don't give us a history lesson, just get rid of this outmoded, 
>artifact of days gone by... Walt - K2WK

Ooops, I did not want to start with a 10 minute rule discussion, but as we
are at it, here is what I think.

If you abandon the 10 minute rule, there will be little or no difference
between multi single and multi multi operations. Multi singles will set up
stations to man 6 bands full time, just assuring only one transmitter goes
on the air at a time. No, 10 minute rule should stay.

Peter. - on6tt.

p_casier at ub4b.eunet.be


>From Norton, Richard" <nortonr at MRD.SRL.dsto.gov.au  Fri Sep  2 19:50:00 1994
From: Norton, Richard" <nortonr at MRD.SRL.dsto.gov.au (Norton, Richard)
Date: Fri, 02 Sep 94 11:50:00 PDT
Subject: WRTC  Rules Comments
Message-ID: <2E67744D at msmail.dsto.gov.au>


I agree with most of the items Bob Cox brought up regarding the proposed 
WRTC rules. I've floated a few of my ideas past some friends and now send 
them to all for comment.

I too, like Bob was one of the WRTC judges in Seattle, and most of what I 
say here is based on my experience there.

My suggestions are made in an effort to:

1) Make the competition fair and equal for all competitors

2) Make the operators demonstrate some "operating skill and knowledge" to 
win

My present thoughts are:

1) Contest should be on CW only to minimize the home court advantage. The 
home court advantage is already tremendous, in that propagation and 
callsigns are easily  known for locals. On phone, the identity of the 
operator becomes obvious to experienced contesters, and friends tend to try 
to help their friends. How would you like to operate in Bulgaria with many 
local Bulgarian speaking stations available to you if you had the right 
accent?

2) All CW should be sent with a paddle. This includes CQs as well as 
exchanges. I come close to thinking programmable keyers are ok, but feel 
that sophisticated computer programs that do all of the sending will 
eliminate the chances of anyone not currently using computers.  This may 
include guys such as UAs who can't afford them who otherwise possess  what I 
think are praiseworthy operating skills.

3) Computers should be used for logging only, not keeping dupe sheets or 
comparing entries to a callsign database.

4) Packet should not be used at all by anyone during the contest. This 
includes not only the on-site contestants, but everyone in the world. The 
sponsors should request that no one put packet spots out during the contest 
anywhere in their announcements. This will minimize any exclusive friends - 
working - friends QSOs.

5) On-site entrants should not identify themselves to friends in any way to 
use friendship to garner exclusive contacts. This could mean they should not 
even say HEJ, or whatever, to their fellow countrymen in an attempt to make 
themselves known. The outcome should be a function of skill and not a 
popularity contest or combined display of ethnic or geographic solidarity by 
the guys back home.

6) The contestants should be given equal stations. This probably means 
setting up in tents with equal antennas. The contestants should be spaced 
far enough apart so that one on the edge of the group does not have an 
advantage in less local QRM. Last time the stations with the high scores had 
the best stations.

7) I'd almost like to use the Sprint QSY rule, but  I think the USA guys 
with Sprint experience would have too big an advantage.

I've already heard that the event should be primarily a social event with a 
contest associated with it, and whoever wins isn't important. Whereas as 
this was known to some of us insiders at the last event, the subsequent 
publicity seemed not to emphasize that aspect. I think everything that can 
be done to make the contest a fair one should be done.

73,

Dick N6AA NORTONR at MRD.SRL.DSTO.GOV.AU

>From Norton, Richard" <nortonr at MRD.SRL.dsto.gov.au  Fri Sep  2 20:32:00 1994
From: Norton, Richard" <nortonr at MRD.SRL.dsto.gov.au (Norton, Richard)
Date: Fri, 02 Sep 94 12:32:00 PDT
Subject: Specific Comments on K3EST's WRTC Proposals from N6AA
Message-ID: <2E677E68 at msmail.dsto.gov.au>


> 1. There is no way to make distant stations equal.
>
Agree, and stated even stronger, there is no way to make home stations 
equal.

> 2. The method of selection of who goes is wrong.
>
Probably true, but it's a real tough job. I think the idea used last time of 
national organizations selecting teams with both exceptions and balance 
given to heavily amateur populated countries worked somewhat ok. Probably a 
smart and just contest dictator would be as good as any.

> 3. There is no tape recording provision.

Agree strongly. The tapes solved all disputes.

> 4. The use of packet is not right.

Agree strongly. This applies to both the negligible demonstration of skill 
for participants in addition to promoting the friends-working-friends 
problem.

> 5. Removing all unique QSO's is ...(other words for "undesirable").

I sort of disagree. This isn't a bad idea. The objective of the contest is 
to demonstrate skill, not work exclusive contacts with fellow countrymen. 
With E-mail we could have a large log database from ouside the on-site 
competitors soon after the contest. Letting people know ahead of time that 
their contacts will not count unless they work a number of stations might 
encourage them to actually work a few guys.
>

> 6. This time limit is too short.

No strong feeling either way. It is possible that some teams may log on 
paper and the electronic version of their log might not be ready by then.

> How can the WRTC be fair?
> 1. Forget about the previous WRTC. It was not fair. I suggest to
> you that the winning teams are selected by a combination of 3
> events.
>    A. The on the air contest during the IARU test. CW QSO's count
> 3 times as much as SSB QSO's. This helps to eliminate the advantage
> the English speakers might have. The stations CAN NOT BE MADE
> EQUAL.

I've already suggested that CW only be used and equal stations be provided.


>   B. A PED test(CW, SSB or Both) of some sort. The teams operate
> JE3MAS's PED pileup simulator for 2 hours. The score is calculated
> by CT. In this case ALL contestants are exactly equal.
>

This isn't completely representative in that you can't tune stations to a 
pitch that you like. The suggestion has merit in the equality sense, but is 
probably too artificial or sterile. Having runners all race in the same lane 
at separate times, and comparing the achieved results may be a fair way to 
run the Olympics, but isn't done today.


>   C. A CW speed copying test. This may require that a member of the
> team is a cw CHAMPION or a Fox hunt.
>
> Each event carries the weight of some amount of points(say 10 for
> the top score). The overall winner is the combination of the three.
>

Again, I think this makes the event too sterile and takes the excitement out 
of it.

> Let's try to make this one right.
> There is still plenty of time to iron out the wrinkles.
>
> 73 Bob K3EST
>


73, Dick Norton N6AA,    NortonR at MRD.SRL.DSTO.GOV.AU



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