Groups > sci.electronics.design > #519519

Re: Dispersion in Coax

From	Frank Miles <fpm@u.washington.edu>
Newsgroups	sci.electronics.design
Subject	Re: Dispersion in Coax
Date	2018-10-16 21:48 +0000
Organization	A noiseless patient Spider
Message-ID	<pq5map$8c5$1@dont-email.me> (permalink)
References	<e5e3e9b8-02ed-4053-9b16-75f88c350a79@googlegroups.com> <rdgcsdh6hsdu96hlr7s9jsgsqe8lnb46pp@4ax.com>

Show all headers | View raw

On Tue, 16 Oct 2018 13:03:23 -0700, Jeff Liebermann wrote:

> On Tue, 16 Oct 2018 11:27:36 -0700 (PDT), George Herold
> <gherold@teachspin.com> wrote:
>>I figure it will be very hard.. needing fast edges and a fast 'scope.  
>>But I wondered if there was some other transmission line 
>>where it would be easier to see. twisted pair or something.  
> 
> Older Tek scopes had a coaxial delay line for the input signal so that
> Tek could implement a delayed trigger feature.  
> <http://w140.com/tekwiki/wiki/Delay_line>
> If there was any phase distortion or group delay in the coax, the
> signal delivered to the vertical input would appear distorted on the
> CRT.

Ah, almost.  If the delay line had no group delay, it wouldn't
provide any delay.  However it has to be constant (or nearly so)
within the bandpass, else the waveform becomes distorted.

My dim recollection from the time I worked at Tek was the delay
line's HF attenuation resulted in the waveform "dribbling up".
WAG: from lumped-element delay lines, in which there might have
been a non-monotonic frequency response.

  -F

Thread

Dispersion in Coax George Herold <gherold@teachspin.com> - 2018-10-16 11:27 -0700
  Re: Dispersion in Coax Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2018-10-16 14:35 -0400
    Re: Dispersion in Coax George Herold <gherold@teachspin.com> - 2018-10-16 12:03 -0700
    Re: Dispersion in Coax Jeff Liebermann <jeffl@cruzio.com> - 2018-10-16 13:13 -0700
      Re: Dispersion in Coax John Larkin <jjlarkin@highland_snip_technology.com> - 2018-10-16 15:50 -0700
        Re: Dispersion in Coax Jeff Liebermann <jeffl@cruzio.com> - 2018-10-16 16:31 -0700
          Re: Dispersion in Coax John Larkin <jjlarkin@highland_snip_technology.com> - 2018-10-16 16:49 -0700
          Re: Dispersion in Coax George Herold <gherold@teachspin.com> - 2018-10-16 17:00 -0700
            Re: Dispersion in Coax Jeff Liebermann <jeffl@cruzio.com> - 2018-10-16 17:53 -0700
              Re: Dispersion in Coax krw@notreal.com - 2018-10-16 21:00 -0400
                Re: Dispersion in Coax Jeff Liebermann <jeffl@cruzio.com> - 2018-10-16 18:16 -0700
                Re: Dispersion in Coax Waussie <waussie@notwa.com.au> - 2018-10-17 13:04 +0800
      Re: Dispersion in Coax Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2018-10-16 20:52 -0400
        Re: Dispersion in Coax Jeff Liebermann <jeffl@cruzio.com> - 2018-10-16 18:08 -0700
  Re: Dispersion in Coax John Larkin <jjlarkin@highland_snip_technology.com> - 2018-10-16 12:22 -0700
  Re: Dispersion in Coax Jeff Liebermann <jeffl@cruzio.com> - 2018-10-16 13:03 -0700
    Re: Dispersion in Coax Frank Miles <fpm@u.washington.edu> - 2018-10-16 21:48 +0000
      Re: Dispersion in Coax John Larkin <jjlarkin@highland_snip_technology.com> - 2018-10-16 16:07 -0700
        Re: Dispersion in Coax Clifford Heath <no.spam@please.net> - 2018-10-17 10:31 +1100
          Re: Dispersion in Coax John Larkin <jjlarkin@highland_snip_technology.com> - 2018-10-16 16:54 -0700
            Re: Dispersion in Coax George Herold <gherold@teachspin.com> - 2018-10-16 17:04 -0700
            Re: Dispersion in Coax Clifford Heath <no.spam@please.net> - 2018-10-17 11:38 +1100
      Re: Dispersion in Coax Jeff Liebermann <jeffl@cruzio.com> - 2018-10-16 16:19 -0700
        Re: Dispersion in Coax "tom" <tmiller11147@verizon.net> - 2018-10-16 19:46 -0400
          Re: Dispersion in Coax Jeff Liebermann <jeffl@cruzio.com> - 2018-10-16 20:35 -0700
  Re: Dispersion in Coax "Tim Williams" <tiwill@seventransistorlabs.com> - 2018-10-16 16:55 -0500
    Re: Dispersion in Coax George Herold <gherold@teachspin.com> - 2018-10-16 15:48 -0700
      Re: Dispersion in Coax "Tim Williams" <tiwill@seventransistorlabs.com> - 2018-10-17 03:49 -0500
  Re: Dispersion in Coax Martin Brown <'''newspam'''@nezumi.demon.co.uk> - 2018-10-17 13:03 +0100
    Re: Dispersion in Coax George Herold <gherold@teachspin.com> - 2018-10-17 06:21 -0700
    Re: Dispersion in Coax makolber@yahoo.com - 2018-10-17 06:41 -0700
      Re: Dispersion in Coax John Larkin <jjlarkin@highlandtechnology.com> - 2018-10-17 08:51 -0700
        Re: Dispersion in Coax dplatt@coop.radagast.org (Dave Platt) - 2018-10-17 11:14 -0700
      Re: Dispersion in Coax Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2018-10-17 11:54 -0400
  Re: Dispersion in Coax gerald_zani@brown.edu - 2018-10-17 06:23 -0700
    Re: Dispersion in Coax George Herold <gherold@teachspin.com> - 2018-10-17 06:48 -0700
      Re: Dispersion in Coax Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2018-10-17 11:15 -0400
    Re: Dispersion in Coax John Larkin <jjlarkin@highlandtechnology.com> - 2018-10-17 08:56 -0700
      Re: Dispersion in Coax "Tim Williams" <tiwill@seventransistorlabs.com> - 2018-10-17 15:59 -0500
      Re: Dispersion in Coax bill.sloman@ieee.org - 2018-10-17 20:39 -0700
  Re: Dispersion in Coax tlbs101 <thomas.pounds101@gmail.com> - 2018-10-29 13:19 -0700
    Re: Dispersion in Coax jrwalliker@gmail.com - 2018-10-29 16:04 -0700
      Re: Dispersion in Coax Jasen Betts <jasen@xnet.co.nz> - 2018-10-30 04:26 +0000
        Re: Dispersion in Coax Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net> - 2018-10-30 10:55 -0400
          Re: Dispersion in Coax jrwalliker@gmail.com - 2018-10-30 13:13 -0700
            Re: Dispersion in Coax upsidedown@downunder.com - 2018-10-31 07:42 +0200
      Re: Dispersion in Coax upsidedown@downunder.com - 2018-10-31 07:36 +0200
        Re: Dispersion in Coax jrwalliker@gmail.com - 2018-10-31 01:12 -0700

csiph-web