impedance comverter

[yukanti]

hallo...<p>need help (again) in designing an IMPEDANCE CONVERTER. now i'm making a active filter that consits High-Pass, Low-Pass, Band-Pass Filter.
An Impedance Convertr is required on that modul.... <p>thanks

[Chris Smith]

They have a slide rule type of calculator for the task, and Im sure its computerized by now. <p>Check with the manufactures of chokes and coils?<p>I got my free cardboard slide rule back many years ago. Very handy.

[russlk]

There are circuits that use a capacitor to simulate an inductor and vice-versa. Is that what you mean by "impedance converter"?

[jwax]

yukanti- We need details!

[Bernius1]

Maybe a novice reply, but;
what about a transformer? Maybe wind your own. 100 turns of 22AWG with 110 turns of 32AWG over that, on a ferrite rod.
I will now turn on the light to see what I shot.

[philba]

I'm with jwax - details. He could mean an impedence matcher or something more sophisticated. <p>A great answer to the wrong question is a wrong answer!

[Ron H]

My guess is he's looking for a negative impedance converter.

[terri]

As it appeared in another topic:<p> <blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr>
Sorry, but I said it and I still ain't takin' it back:<p>What is the real problem?<p>And I see this kind of thing all over this board:
"I've got a nitzifez. What can I do?" And it is five
ten, fifteen posts later that the real problem
finally emerges, only after a whole bunch
of "Yeah, buts" from the initial poster.<p>While I recognize that sometimes it is not possible
to state a problem clearly at the outset --maybe there
are too many variables involved and they have to
be sorted out first, but to me, at least, that is
the first job of the poster --to sort out the
variables. And I will guarantee
that about half the time, if the poster starts
sorting out some of these variables, not only
will a more clear statement of the problem
emerge, but the solution as well!<p>As George Zimmerman says, "I guarantee it."
<hr></blockquote><p>[ February 16, 2005: Message edited by: terri ]</p>

[philba]

The problem with long, detailed question posts is that they seldom gather many responses. I'd guess that people see a long post and mentally go "Next!".

[terri]

You're probably right, regrettably. See the AC motor speed topic. I answered on the reasonable basis that the querent was doing some machining with a fly cutter. Silly me! I should have read the querent's mind and realized that he was really slicing termite mounds.<p>But of course! Silly me! I should have known!<p>Where's my effing Tarot deck?

[philba]

funny, I though he was building a torture machine to use on a younger sibling...<p>[never ever thought about that when *I* was young... ]

[terri]

It took you to point it out, but come to think of it, it does sound kind of essy and emmy.<p>Eeek!<p>================<p>Now, wouldn't it have been easier all around if the query looked something like this?<p>
TASK: Develop, find, or modify a variable-speed AC motor (1/2 to 3/4 HP) whose torque will be the same regardless of RPM in driving a large disc cutter. <p>APPLICATION: Slicing sections of termite mounds encased in plaster for scientific measurements of diameters, composition, etc. Maximum diameter of termite mound XX.X cm. Maximum height YY.Y cm. Termite mounds consist of termite-saliva-bound grains of sand and small pebbles. <p>PROBLEM/QUESTION: We are having difficulty in driving an AC Motor at variable RPM with sufficient torque to do the cutting. How can we do this without using feedback circuits? (Note: type of motor tried was not specified, i.e., induction, universal.)<p>=================<p>Yes?<p>No?<p>How would you have answered if the querent had posed the question that way?<p>[ February 18, 2005: Message edited by: terri ]</p>