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----- Original Message -----

From: kevin kearns

To: [email protected]

Sent: Saturday, February 23, 2019 8:11 AM

Subject: Re: [HP-Agilent-Keysight-equipment] 8970B Problem

Hi All,?

?

?Does anyone else notice that it takes longer?for the NF reading to stabilize?compared with?the gain figure on the 8970B? When you calibrate the machine after a few minutes after switch on, gain reads zero and is stable. NF will read zero straight after cal?but drifts a bit, so it takes 10 mins warm up or so for the reading to?stay at zero after cal.

?

Checking the machine with a precision 6.0 dB attenuator, Gain reads 6.01dB and NF reads 6.10 dB when all warmed up.

Kevin

----- Original Message -----

From: alwyn.seeds1

To: [email protected]

Sent: Friday, February 22, 2019 11:26 PM

Subject: Re: [HP-Agilent-Keysight-equipment] 8970B Problem

Dear All,

Many thanks for your advice, especially to “nj902” who pointed me to the explanation.

I’ve now verified what happens as gain/NF of the measured object is changed and it is nice to find that this is not a fault.

Regards,

Alwyn

From:?nj902
Date: Thu, 21 Feb 2019 21:22:23 PST?

Apparently, this is normal.

Look up Agilent (Keysight) Application Note 1484? "Non-Zero Noise Figure After Calibration"

_____________________________________________________

Alwyn Seeds, Director
SynOptika Ltd.,
114 Beaufort Street,
London,
SW3 6BU,
England.

Tel.: +44 (0) 20 7376 4110


SynOptika Ltd., Registered in England and Wales: No. 04606737
Registered Office: 114 Beaufort Street, London, SW3 6BU, United Kingdom.

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