[time-nuts] Agilent appnote
phk at phk.freebsd.dk
Mon Jul 25 06:53:27 EDT 2005
In message <20050725.124305.26278789.cfmd at bredband.net>, Magnus Danielson writes:
>From: "Joseph Gray" <jgray at zianet.com>
>Subject: [time-nuts] Agilent appnote
>Date: Mon, 25 Jul 2005 01:46:35 -0600
>Message-ID: <037401c590ec$fba12210$66fea8c0 at antecp4>
>> Does anyone have a copy of Agilent appnote 174-10 "Measuring the electrical
>> length (delay) of cables"? A search of the Agilent site doesn't find it.
>Sadly, I don't have that App-note, however...
>May I propose that you take a sufficiently low frequency (100 kHz may suffice)
>squarewave, split it so that you trigger START (directly, put the splitter on
>the start BNC) and then the other output of the splitter goes to the cable
>which connects to the STOP channel. Measure and preferably integrate over some
>100 measurements at least.
>That is at least what I would assume that 174-10 says:
Normally this is done with a network analyzer by measuring the phase difference
at two different frequencies and calculating which delay would cause that.
Poul-Henning Kamp | UNIX since Zilog Zeus 3.20
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