On Tue, 11 May 2004 01:27:50 GMT, "Jerry Martes"
wrote:

[snip]

Let's establish something first. I used to instruct a fourth
year/graduate level microwave measurements lab in which experiment #1
was on the use of slotted lines.

|
| I wonder why such a smart guy like you would ask about how a person would
|machine a straight slot where a "sraight slot" (sic) isnt (sic) even needed.

If you don't think the longitudinal slot needs to be straight down the
length of the line then let's stop here.

If I can convince you that it needs to be then we can proceed.

|Why would
|you propose (the) use of "soft copper"(?)

Perhaps I shouldn't have said "soft" copper; nevertheless, copper
isn't the easiest material to machine, and it was you, you should
recall, that mentioned the use of copper water pipe. If you have a
milling machine with five or six feet of table travel, then good for
you, have at it.

|And, why would you put any supports on the
|center conductor when it isnt (sic) necessary to put them on top, where the probe
|would.be.(?)

The center conductor needs to be precisely located so as to not have
the probe coupling vary as it is moved. This will necessitate a fair
number of disks/beads or whatever. To be precise, the center
conductor diameter should be reduced (or the outer conductor
increased) wherever there is a dielectric support. If you intend to
slot the supports, then the missing dielectric will modify the
effective dielectric constant. Be sure and calculate that effect.


|Besides, at 137 MHZ, is wouldnt be all that necessary to have
|the probe moveable continuously.

Oh, I didn't know that. Apparently General Radio didn't either; they
had a micrometer attached to theirs to measure position to the
thousandths of an inch.

|It is aparent to me that either you want
|to diminish the value of my learning project or you are just not smart.

Why thank you!

|I havent read this antenna news group for very long.

I have, although with some of the inane stuff posted lately, it isn't
often. BTW, it's an *amateur radio* group. I didn't know we had a
band at 137 MHz.

|Your *help* to me is
|hopefully not typical.

No, I believe in this instance that the advice Richard gave you and
what I am trying to give you is atypically better that what you will
usually get.

|I'm trying to learn. What are you trying to do??

Beats the hell out of me.