On Oct 1, 9:09 pm, Cecil Moore wrote:
Jim Kelley wrote:
In a DC circuit, the
current is the same throughout the circuit.

That's true only for a simple series circuit. And it's true for RF as
well.

A foot of wire with reflections at one GHz has
the same current throughout the circuit?
--
73, Cecil http://www.w5dxp.com

A simple series circuit can be expected to behave as a simple series
circuit. Other circuits can be expected to behave differently. Which
do you think applies?

ac6xg

Jim Kelley wrote:
Cecil Moore wrote:
A foot of wire with reflections at one GHz has
the same current throughout the circuit?

A simple series circuit can be expected to behave as a simple series
circuit. Other circuits can be expected to behave differently. Which
do you think applies?

An *ordinary prudent man* would think that one foot
of wire is a "simple series circuit" and it is in a
DC circuit. If as you say, the current in an RF circuit
is the same throughout, why does the current vary
every inch in a circuit with reflections?
--
73, Cecil http://www.w5dxp.com

Cecil Moore wrote:
Jim Kelley wrote:

Cecil Moore wrote:

A foot of wire with reflections at one GHz has
the same current throughout the circuit?


A simple series circuit can be expected to behave as a simple series
circuit. Other circuits can be expected to behave differently. Which
do you think applies?


An *ordinary prudent man* would think that one foot
of wire is a "simple series circuit" and it is in a
DC circuit.

Most ordinary prudent men that I know wouldn't characterize a one foot
length of wire as a series circuit.

ac6xg

Jim Kelley wrote:

Most ordinary prudent men that I know wouldn't characterize a one foot
length of wire as a series circuit.


Come on now guys, let's get series!

- 73 de Mike KB3EIA -

On Oct 2, 10:33 am, Jim Kelley wrote:
Cecil Moore wrote:
Jim Kelley wrote:

Cecil Moore wrote:

A foot of wire with reflections at one GHz has
the same current throughout the circuit?

A simple series circuit can be expected to behave as a simple series
circuit. Other circuits can be expected to behave differently. Which
do you think applies?

An *ordinary prudent man* would think that one foot
of wire is a "simple series circuit" and it is in a
DC circuit.

Most ordinary prudent men that I know wouldn't characterize a one foot
length of wire as a series circuit.

ac6xg

The fact that it's described as having a physical dimension suggests
that the physical extent matters. I don't know what an "ordinary
prudent man" is, but I suppose most people I stopped on the street
wouldn't have a clue what I was talking about and their eyes would
kind of glaze over with the mention of "wire" and "circuit."

Cheers,
Tom

(presently playing with circuits below 100MHz where 1mm can make a
huge difference in performance...who finds folk who say we don't
understand such things as distributed circuits deeply offensive,
especially when they make it abundantly clear they don't understand
such circuits themselves...)

Jim Kelley wrote:

Cecil Moore wrote:
An *ordinary prudent man* would think that one foot
of wire is a "simple series circuit" and it is in a
DC circuit.

Most ordinary prudent men that I know wouldn't characterize a one foot
length of wire as a series circuit.

More silly word games - when it is in a DC circuit
the current is constant. When it exists in a simple
series GHz circuit with reflections, the current
is not constant.
--
73, Cecil http://www.w5dxp.com

"Cecil Moore" wrote in message
news
Jim Kelley wrote:

Cecil Moore wrote:
An *ordinary prudent man* would think that one foot
of wire is a "simple series circuit" and it is in a
DC circuit.

Most ordinary prudent men that I know wouldn't characterize a one foot
length of wire as a series circuit.

More silly word games - when it is in a DC circuit
the current is constant. When it exists in a simple
series GHz circuit with reflections, the current
is not constant.
--
73, Cecil http://www.w5dxp.com

you don't even need reflections. a properly terminated piece of wire has a
different current at every point along the wire.

Dave wrote:
you don't even need reflections. a properly terminated piece of wire has a
different current at every point along the wire.

That's true but the attenuation factor in one foot
of wire might be hard to measure. Introduce reflections
and even a lossless wire will vary the current from
max to min every few inches at GHz frequencies.
--
73, Cecil http://www.w5dxp.com

"Cecil Moore" wrote in message
...
Dave wrote:
you don't even need reflections. a properly terminated piece of wire has
a different current at every point along the wire.

That's true but the attenuation factor in one foot
of wire might be hard to measure. Introduce reflections
and even a lossless wire will vary the current from
max to min every few inches at GHz frequencies.
--
73, Cecil http://www.w5dxp.com

you don't need any loss either. a properly matched lossless line will have
different current at each point along the line.

Dave wrote:
"Cecil Moore" wrote in message
news
Jim Kelley wrote:

Cecil Moore wrote:

An *ordinary prudent man* would think that one foot
of wire is a "simple series circuit" and it is in a
DC circuit.

Most ordinary prudent men that I know wouldn't characterize a one foot
length of wire as a series circuit.

More silly word games - when it is in a DC circuit
the current is constant. When it exists in a simple
series GHz circuit with reflections, the current
is not constant.
--
73, Cecil http://www.w5dxp.com


you don't even need reflections. a properly terminated piece of wire has a
different current at every point along the wire.

At any given instant. :-)

ac6xg