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Old February 1st 14, 11:03 AM posted to rec.radio.amateur.antenna,sci.electronics.basics
John S John S is offline
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First recorded activity by RadioBanter: May 2011
Posts: 550
Default I have question about R L Mathematics

On 1/31/2014 3:32 PM, Sal M. O'Nella wrote:

"amdx" wrote in message
...


It amazes me that I can see the the delay in a short piece of wire.
All of the sudden I see a value in my new 300 Mhz scope. Lower time base.


OFF TOPIC, SLIGHTLY:

With a wideband scope, you see many interesting things, including some
that might surprise you. Years ago, while looking at some short pulses
(to evaluate the response of a new amplifier), I saw unexpected "steps"
in the traces. I was using BNC T-connectors and my test setup had
accidentally duplicated a TDR function. The impedance change
reflections were plainly evident in a few feet of 50-ohm coax. (I've
since seen plans for a home-brew TDR similar to my accident. :-)

I enjoy amazement, too.

"Sal"
(KD6VKW)


Right you are, Sal. I once used a 200MHz scope and a pulse generator to
measure the approximate length of a reel of coax. Handy stuff to know.

John S
KD5YI