Did you also receive a calibration kit with the VNA? If you did so, then the
lengths of these interconnect cables are not crucial for calibrated
measurements. Only uncalibrated measurements will be affected.

It would help to know the manufacturer and model of the VNA.

Wayne
(KC8UIO)
"Paul Burridge" k wrote
in message ...
Hello guys,

I recently picked up an old vector network analyser in working order
but minus the 3 interconnects between it and the
transmission/reflection bridge. These are specified in the manual to
be exactly 24" long, 50 ohms and terminated by N-type plugs.
I've been told the length of these patch leads is quite critical to
getting accurate measurements with this VNA, but am at a loss to work
out why 24" is specified when the frequency range of this device is
4Mhz to 1300Mhz. If it were only capable of measuring at one fixed
frequency, I could understand the need for a specifically cut length
of some fraction of a wavelength.
Can anyone explain the relevance of 24" in this context?
Also, will *any* 50 ohm coax suffice for this purpose or has it got to
be something special?
Thanks,
P.
--

"What is now proved was once only imagin'd" - William Blake

On Mon, 05 Dec 2005 02:37:47 GMT, "Wayne P. Muckleroy"
wrote:

Did you also receive a calibration kit with the VNA?

Nope.

If you did so, then the
lengths of these interconnect cables are not crucial for calibrated
measurements. Only uncalibrated measurements will be affected.

It would help to know the manufacturer and model of the VNA.

It's a good old HP 8754A
--

"What is now proved was once only imagin'd" - William Blake