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  1. HP-Agilent-Keysight-Equipment
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E4404B Noise floor with 1DS option

 

Dear list,

I'm hoping to purchase an E4404B for noise measurements between 650MHz and 1GHz.
According to the Datasheet, the floor should be around -130dBm with a 1DS option (RBW = 1kHz).
I'm hoping I to run a simple test on the unit I'm planning to buy to check this...

(i) Terminate the Analyzer input (50ohms)
(ii) Set the scope to scan from 790 to 810 MHz
(iii) Set the RBW to 1kHz
(iv) Grab a screenshot - the noise floor should be around -130dBm


Anyone out there with an E4404B (+1DS option) that can run this simple test for me?

Thanks,
?- Guy.
 

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Hi Guy,

?

I have an E4407B with 1DS option (same specification as the E4404B for noise in the 790-810 MHz band).

So, for the 790-810 MHz band I get -139.6dBm.

?

Yves

?

?

?

De?: [email protected] <[email protected]> De la part de guy_ellis_1964
贰苍惫辞测é?: 30 avril 2024 18:01
??: [email protected]
Objet?: [HP-Agilent-Keysight-equipment] E4404B Noise floor with 1DS option

?

Dear list,

I'm hoping to purchase an E4404B for noise measurements between 650MHz and 1GHz.
According to the Datasheet, the floor should be around -130dBm with a 1DS option (RBW = 1kHz).
I'm hoping I to run a simple test on the unit I'm planning to buy to check this...


(i) Terminate the Analyzer input (50ohms)
(ii) Set the scope to scan from 790 to 810 MHz
(iii) Set the RBW to 1kHz
(iv) Grab a screenshot - the noise floor should be around -130dBm


Anyone out there with an E4404B (+1DS option) that can run this simple test for me?

Thanks,
?- Guy.

image_19_39_12.png

 

Hi Yves,

Wow that is fantastic.

With my old 8594E I'm struggling to get down to -90dBm, which is about the same level as the noise I'm trying to measure.
To get down that low will make a big difference.

My next challenge is to find a E4404B with 1DS at a reasonable price.

Thanks very much,

Kind regards,
?- Guy
 

If you only need to operate up to 1GHz, one cheaper option is to make an external wideband preamp (eg 30dB gain) for the HP 8594E and then offset the amplitude reference level by the gain of the preamp. It should be possible to make a preamp with a sub 4dB noise figure and flat gain up to 1GHz using cheap MMIC parts from Analog devices or Minicircuits.

The input VSWR up to 1GHz will probably be better than the 1DS preamp as well.

It does look like your HP 8594E is a bit noisier than expected though. -90dBm with a 1kHz RBW is quite poor. Is this with 0dB input attenuation?

Note that if you want to measure noise more accurately, it's best to use the 1Hz noise marker function in the 8594E. This will be better than using a normal marker and a 1kHz RBW.
 

Why not consider a E4402B, lot easier to find

1DS is a software option (if the SA is not to old) and easy to enable

Best
Hans J Eriksen


Den onsdag den 1. maj 2024 kl. 02.02.21 CEST skrev guy_ellis_1964 <guy@...>:


Hi Yves,

Wow that is fantastic.

With my old 8594E I'm struggling to get down to -90dBm, which is about the same level as the noise I'm trying to measure.
To get down that low will make a big difference.

My next challenge is to find a E4404B with 1DS at a reasonable price.

Thanks very much,

Kind regards,
?- Guy

 

What a coincidence, I was just thinking of maybe selling the E4402B that I've just repaired (see my other threads in this group). It's taking more space than I hoped, and I'm not using it nearly as much as I thought I would. PM me if interested.
 

Have a look at the following thread on eevblog's forum:



The guy to contact is: "PA0PBZ". It seems to be a key generated from the serial number.

Also, "fenugrec" (or any other people), do you have a spare tracking generator for sale? I need a 3GHz one for my E4402B.

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