Video Agilent 53131A Universal Counter Upgrade OPT-030 Analysis and Experiments

[Hugoneus]

In this episode, Shahriar upgrades an Agilent 53131A Universal Counter with the OPT-030 which extends its frequency range from 225MHz to 3GHz. The upgrade kit is a replica PCB intended to emulate the behavior of the original Agilent branded option.

The PCB is examined carefully with attention to microwave layout techniques along the signal path. The datasheet of all the parts are reviewed and the reverse-engineered block diagram of the PCB is presented. The expected behavior of the PCB is then measured in both small-signal and large-signal operation using an active 3GHz probe. The PCB is then installed inside the unit and the functionality of the instrument is verified within its specifications. All the documents presented in the video can be found at The Signal Path Blog.

Watch the video here: [51 Minutes]
http://youtu.be/21_9Dspzu_w

More videos at:
http://www.TheSignalPath.com

[berk98]

Excellent video! Always happy to see new ones.

I have a GPS based disciplined oscillator.  It's a bit annoying to use, and it's actually currently on loan to someone else.  But if you don't find a better option in a while (and you have a good place for an antenna), I'd be glad to ship it over.

There will be no question over accuracy, too, although next to an OCXO, a rubidium standard will be fine.

Keep up the great videos.

[vaualbus]

I see on the agilent site that there is an option to go to 12ghz. Would be the circuit different? It could be custom amplifier and custom dividr chip or the circuit would be different?

[Hugoneus]

I see on the agilent site that there is an option to go to 12ghz. Would be the circuit different? It could be custom amplifier and custom dividr chip or the circuit would be different?

The principle of operation should be the same: amplify, divide, count. Jus the division ratio has to be higher.

[Lukas]

I'm wondering how it detects the absence of an input signal (around 46:20) since there's no kind of RF detector or power meter on the option board.

[pmcouto]

I see on the agilent site that there is an option to go to 12ghz. Would be the circuit different? It could be custom amplifier and custom dividr chip or the circuit would be different?

The principle of operation should be the same: amplify, divide, count. Jus the division ratio has to be higher.

Hi,

Unfortunately, building a 12 GHz prescaler for the HP 53131A is not that simple…

Have a look at this thread:

https://www.eevblog.com/forum/testgear/hp-53131a53132a53181a-high-stability-timebase/msg300677/#msg300677

[Hugoneus]

I see on the agilent site that there is an option to go to 12ghz. Would be the circuit different? It could be custom amplifier and custom dividr chip or the circuit would be different?

The principle of operation should be the same: amplify, divide, count. Jus the division ratio has to be higher.

Hi,

Unfortunately, building a 12 GHz prescaler for the HP 53131A is not that simple…

Have a look at this thread:

https://www.eevblog.com/forum/testgear/hp-53131a53132a53181a-high-stability-timebase/msg300677/#msg300677

Thank you. Yes it is more difficult to build a presaler at 12GHz... But it is ultimately doing the same thing. I should take apart my 20GHz frequency counter and have a look.

[Hugoneus]

I'm wondering how it detects the absence of an input signal (around 46:20) since there's no kind of RF detector or power meter on the option board.

Either it looks for activity on the divided output or there is a peak detector on the board. There is an extra diode after the amplifier which I didn't talk about. I'll have to look if they are using that as a peak detector.

[HighVoltage]

What a great video.
Thank you

[Hugoneus]

What a great video.
Thank you

Thanks! I am working on a new video... This one needs a lot of preparation.

[Fsck]

Excellent video as always, really wish you had more time in your life to dedicate to these videos!