Polar and Vector quantities.

On Fri, 25 Nov 2005 12:42:33 +0100, Paul Burridge wrote: [snip]

You're welcome.

I would expect that minus wear marks and scratches, the instrument would otherwise be as new: Dust and grime removed, inside and out; all connectors torqued to spec; fans cleaned and lubed; filters cleaned or replaced; switches and pots cleaned/lubed; broken knobs replaced; etc.

And of course, the box would be fully functional and calibrated to factory specs.

Hi all,

Probably a stoopid question, but if a network analyzer is capable of displaying readings in polar form (but not in Smith chart format) is it still classed as a vector network analyzer? I'm in discussions to buy an HP 8754A but don't want it if it's scalar only. Can't find anything on the web to assist. :-(

Paul

Thanks, Wes. I was pretty sure that was the case but just needed to be certain.

Yep, noted and thanks again.

As an aside, I see the company in your link sells "refurbished" analyzers. I wonder what exactly is done to them that counts as refurbishment? I guess it varies from supplier to supplier, but anyone have any idea what one might reasonably expect to be done?

A smith chart is simply a grid distorted so that the impedance can be read off a polar plot of the reflection coefficient S11. I'm not aware of the existence of an HP8754, but if you were talking about the HP8753, then yes, that's a vector network analyser. It *does* make Smith charts too.

Jeroen Belleman

Save yourself a bundle and buy a used HP Vector Voltmeter. It will measure amplitude and phase and compared to a network analyzer is virtually impervious to RF interference if working in a high rf environment. :-)

Have a look at this one.

I have an 8405A and I love it. One word of advice -- get one guaranteed to work. The probes have some diodes and FETs in them to do the sampling so they are somewhat susceptible to failure if mishandled. The manual warns of probe burn-out if more than 2V peak AC or 50VDC is encountered.

Cheers, John