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Agilent 8714ET Opt 100 Velocity Factor problem?

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wd5jfr:
I wanted to check the velocity factor on some blue Gore mini-coax that looks like RG-174 but with braided shield and silver plated  center conductor with teflon dielectric.  I've confirmed it's 50 ohm by measuring the capacitance and inductance and calculating, result is 50 ohms. After several attempts I think I have the correct command sequence, hard keys are in all caps and soft are lower case.

PRESET
BEGIN
    User begin (turned OFF)
    Cable
    Fault location
CAL
    Calibrate cable
    Specify length (enter number of feet)
    Measure cable

The response I get is "loss or velocity out of range"

I've tried this on known  good 50 feet of RG213 and 100 feet of RG174 with same result.  I think I have the correct command set and I wonder if anyone can confirm this and let me know it's me or the 8714ET.
Thanks

KrudyZ:
Works on my 8714ET, but I used a much shorter cable (4ft).
It gave a reasonable velocity factor of 0.68.
Make sure the cable is unterminated.

wd5jfr:
The manual says use at least 30 feet. 
So I'll try something shorter and let you know what I get.
Did you use the exact same steps I posted?
Thanks

wd5jfr:
I just tried a 6 ft BNC jumper and it came with a velocity of 0.74 which sounds reasonable.  Then the RG213 tested OK, dirty connector. Currently I have no way to connectorize the RG174 or the Gore cable so I used a solder turret banana plug to BNC and  now I suspect it's the impedance mismatch at the 8714 and the DUT that is upsetting the reading.  So now I have to figure out what kind of connectors I'm going to use for the Rg174 and Gore cables: crimp vs solder, BNC vs SMA and minimize expense since I don't think I see me making more than 10 cables.  HF to 2 meters & maybe 440 is the limit.  I'm 82 and would appreciate recommendations economical connectorization for RG174.
Thanks

KrudyZ:
The shortest length it let me enter was 1m, so I'm assuming that you can measure cables shorter than 30ft.
WRT connectors for RG174, you can get SMA, BNC and type N.
Out of the three I would pick SMA, but what you should choose of course this depends on how you want to use the cable you make.
I have N to SMA adapters on my HP8714ET and use SMA for pretty much everything >1GHz.

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