[time-nuts] 75Z vs 50Z for GPS receivers

[Poul-Henning Kamp]

In message <45BD1880.9080503 at xtra.co.nz>, Dr Bruce Griffiths writes:

>I can see the difference between the short 50 ohm cable terminated in 50 
>ohms and the short 50 ohm cable terminated in 75 ohms.
>It would be instructive to repeat this with a short length of 75 ohm 
>cable terminated in50 and 75 ohms.

The technique for visualizing these kinds of things is called Time Domain
Reflectometry and you can do it with a good pulse generator and an
oscilloscope.

A HP5359A is perfect for the job, but less will do it.

Read here how-to:

	http://www.hparchive.com/Application_Notes/HP-AppNote-62.pdf

Poul-Henning

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