HP 5372A Freq / Time Interval Analyzer, Option 040 FFT / Jitter Analysis

[garrettm]

I just picked up an HP 5372A with options 020 (FastPort) and 030 (Input C 100MHz to 2GHz) for $200 USD, which I feel is a decent deal (as optioned, it sold for $33,750 in 1993!). The unit in question turns on with "Error 160: Out of sensitivity cal.". The service manual says this is a dead 3.6V battery on A7 and will require replacing the battery and performing the A2 sensitivity adjustment. So nothing too daunting (in theory at least!).

Anyways, I noticed that the 1993 HP Catalog lists option "040 Jitter Analysis", but my unit with SN 3045A doesn't show this as an option on the rear panel. After reviewing the service manual available online, it appears HP made two more major revisions after mine: 3141A and 3301A. Looking at photos of a unit with SN rev 3301A indeed shows "040 FFT" on the rear panel. Clearly, this option was introduced with either revision 3141A or 3301A (I'm not sure which).

I was curious if this option was an actual hardware change or a software feature added later on? And, if so, could it be enabled with newer firmware on an older unit? Does anyone know more about this option and if this might be possible?

[benj38]

Looks like a purely software option to me.
https://www.artisantg.com/info/Agilent_5372A_Option_40_Manual.pdf

[garrettm]

Thank you benj38! The manual states that FW version 3127 or newer is required. It seems plausible that this software option was introduced with SN rev. 3141A instruments.

If anyone would be kind enough to upload a copy of the 3127 or newer FW I would be very grateful.

I believe enabling this option will require not only newer FW but flipping one or two dip switches, but I didn't notice the service manual ever mention option 040 so I'm not sure which switch/es need setting. I don't think it would be very hard to figure it out though.