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William E. Sabin September 16th 03 12:38 PM

Jack Smith wrote:

Bill:

Your March 1995 QEX article says that you prepared an accompanying
construction article for QST. I haven't been able to find it in '95,
96 or '97 QST editions. Was it published? If so, when?

Jack K8ZOA



I did not write a construction article, but QEX
for May 1995 has an article on the design of the
transformers for the directional coupler. Actual
construction articles have been described in ARRL
Handbook and Antenna Book editions.

Bill W0IYH


Jack Smith September 16th 03 12:58 PM

On Tue, 16 Sep 2003 06:38:21 -0500, "William E. Sabin"
sabinw@mwci-news wrote:

Jack Smith wrote:

Bill:

Your March 1995 QEX article says that you prepared an accompanying
construction article for QST. I haven't been able to find it in '95,
96 or '97 QST editions. Was it published? If so, when?

Jack K8ZOA



I did not write a construction article, but QEX
for May 1995 has an article on the design of the
transformers for the directional coupler. Actual
construction articles have been described in ARRL
Handbook and Antenna Book editions.

Bill W0IYH



Found it. As usual, an excellent piece of work!

Jack K8ZOA



Richard Harrison September 17th 03 08:08 PM

Richard Clark wrote:
"Has anyone here actually measured SWR without using a diode?"

I did something similar and could have used the same rig to measure SWR
in a feedline.

I used a wire loop which included a thermoammeter suspended from a
horizontal antenna element. I pulled this along the element to measure
its current distribution using a long tow rope and a telescope.

Pulled along a transmission line wire, this would have produced the
currents at the minima and maxima along the wire. From these we could
calculate SWR.

Best regards, Richard Harrison, KB5WZI


Richard Clark September 17th 03 08:44 PM

On Wed, 17 Sep 2003 14:08:47 -0500 (CDT),
(Richard Harrison) wrote:

Richard Clark wrote:
"Has anyone here actually measured SWR without using a diode?"

I did something similar and could have used the same rig to measure SWR
in a feedline.

I used a wire loop which included a thermoammeter suspended from a
horizontal antenna element. I pulled this along the element to measure
its current distribution using a long tow rope and a telescope.

Pulled along a transmission line wire, this would have produced the
currents at the minima and maxima along the wire. From these we could
calculate SWR.

Best regards, Richard Harrison, KB5WZI



Bravo Richard!

You response from the wilderness exposes the poverty of experience
within the city of enlightenment. Cake and circus seems to be the
daily fare here.

73's
Richard Clark, KB7QHC

M. J. Powell September 17th 03 09:32 PM

In message ,
Richard Harrison writes
Richard Clark wrote:
"Has anyone here actually measured SWR without using a diode?"

I did something similar and could have used the same rig to measure SWR
in a feedline.

I used a wire loop which included a thermoammeter suspended from a
horizontal antenna element. I pulled this along the element to measure
its current distribution using a long tow rope and a telescope.

Pulled along a transmission line wire, this would have produced the
currents at the minima and maxima along the wire. From these we could
calculate SWR.


This was a common task for the students at Marconi College in the 50's.

The meter was read with binoculars.

Mike
--
M.J.Powell

Richard Harrison September 17th 03 10:26 PM

Mike Powell wrote:
"This was a common task fot the students at Marconi College in the
`50`s."

The student practice had a commercial application. It was in the same
decade but at a different locale. It was during the tune-up of a SW
broadcast curtain array near Lisbon, Portugal.

Best regards, Richard Harrison, KB5WZI



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