NAQP Sum. AD5Q (KB5YVT,op)

kb5yvt at kb5yvt at
Wed Aug 24 09:41:20 EDT 1994


160     2     2
 75    39    22
 40    64    28
 20   371    48
 15    18    12
 10     6     2
      500    114    Score 57,000

Can you say "poor conditions!" Thought you could!

Roy took me under his wing (KT34XA @ 110) to give me a
chance, but the high bands didn't cooperate!  For some reason
we couldn't hear on 40 or 80 ?? Thanks Roy, I'll do better next time!

** Highlight ** Listening to RP work the "Pig Farmers" over on
3.850!! Nice work Bob!!!!!!

>From tim.ellam at (Tim Ellam)  Wed Aug 24 13:26:00 1994
From: tim.ellam at (Tim Ellam) (Tim Ellam)
Date: Wed, 24 Aug 94 07:26:00 -0500
Subject: 1994NAQP VE6SH
Message-ID: <75757.1000.uupcb at>

What a miserable score:

160     0       0
80      18      9
40      79      33
20      38      17
15      1       1
10      1       1

137     61      8,357

1800Z 10 dead(I had trouble making my obligatory croos town contact), 15
even worse, 20 fair; 1901Z neighbour's landscaper puts backhoe through
powerline; 1930Z wait on back deck with a beer for Calgary Power; 2030Z
still waiting; 2300Z still waiting but as the temp was an unheard of 32C
not all bad; 0050Z power back on-but 761 and computer dont work;0115Z
fire up my modified 751 at max power(40W) and install NA on my
notebook;0130Z 20 dead, 40 fair but noisy- 6 hour power loss did it to
my score!

I did finally work N6TR to prove VE6s actually do work contests!!


| Logical Solutions Computer Systems Inc.       Calgary, Alberta, Canada |
| Internet:                   (403)-299-9900 24 Lines  |

>From DFREY" <HARRIS.DFREY at IC1D.HARRIS.COM  Wed Aug 24 16:55:10 1994
Date: 24 Aug 1994 10:55:10 EST
Subject: Open Wire Loss -  Reply to W6SX
Message-ID: <QCY2.DFREY.5949.1994 0824 10 55 10 55>

---------------------------- Forwarded with Changes ---------------------------
From: HARRIS.W6SX at Harris
Date: 8/24/94 4:51AM
Subject: Open Wire Loss

Dear Hank,

I made the measurements about ten years ago when I worked at Ten-Tec.
The comparison was made between 6" open wire line with ceramic spacers
every 10', Zo about 650 ohms, and  450 ohm ladder line. Frequency was
65Mhz, the upper limit of the HP-601.  I used a Boonton rf voltmeter
as the detector. Johnson matchboxes were used at each end to make the
bal-un transition and transform back to 50 ohms.  Identical parallel
250' runs of each were measured.  The difference was 0.5dB favoring
the open wire, which translates to 0.092dB/100' difference at 30 MHz.

Poly does two things: it provides a support/insulation role and makes
the spreaders easily, and as a dielectric, it slightly reduces the
spacing necessary to get to 450 ohms.  The higher the impedance, the
lower the loss.  Windowing the line lowers the weight and the loss -
both the initial dielectric loss and the 'aging loss'.

Polypropylene is an outstanding rf dielectric provided it is not
exposed to uv radiation which causes it (and most other plastics) to
become brittle which decreases strength, causes surface cracks which
permit ingress of contaminants.  The brown opaque fillers added to
prevent uv deterioration do increase the loss somewhat.  Like many
other things in life, nothing is simple!

It is difficult to get good quality 450 ohm open wire line. It is hard
to keep it from twisting shorted on long horizontal runs. The
ladderline is inexpensive, easily obtainable at good quality. And it
won't short by twisting.

Dick Frey

on 8/23 W6SX wrote:

Many thanks for your open wire information.  Have been an open wire
fan for decades.

Just to be sure, is garden-variety poly ladder line (ie, approximately
1" ribbon line with "windows" cut out) really within 0.1 dB/100 ft
of "true" open wire line at 30 MHz?  Seems hard to believe with all
that poly still there.  Is that manufactures data or did someone
actually measure it?

73, Hank W6SX

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