EEVblog #538 - HP35670A DSA Repair - Part 2

[Stonent]

Well he did on their forum, but that was towards the time of the first video, they redirected him to the PSU area and he got no responses.

Why they moved it to the PSU area just baffles me.
But in any case, it looks like the schematics are unobtainium.

Well I guess because initially you were trying to get it to power up so perhaps that's why. Maybe a new posting about the A5 board will get some more hits?

[k2teknik]

But in any case, it looks like the schematics are unobtainium.

I think that HP / Agilent just not have the copyright to publish the schematic, you get that message now and then when you ask for schematic, drivers and other tech questions, the answer goes like, "Sorry we can't give you that because of copyright".
They buy a finish product, branded in there own name, and a part of the "low" price is the missing copyright to publish the schematic etc.

[k2teknik]

You showed a chart of measured power supply voltages, and that got me thinking.  When checking a "maybe bad" power supply, when do you check with a scope and not just a DMM?

For good measure you can add in a scope and one more DMM, then you can measure AC, DC and see the scope picture, all at the same time, and you should do it every time, but we are just human ain't we?

[EEVblog]

They buy a finish product, branded in there own name, and a part of the "low" price is the missing copyright to publish the schematic etc.

There is no way this is not a 100% designed HP product (excluding PSU)

[alm]

If this product was repaired by board exchange in the service centers and they didn't offer a CLIP, then schematics may very well never have existed outside the product development department.

[Fitzroy]

Hey Dave at around 7 mins into the video. You said there was two 5 V rails one being 5V analog and the other being being 5V Digital. So what is difference between those two(other being called digital and Analog)

Thanks
 

[daddario]

Hey Dave at around 7 mins into the video. You said there was two 5 V rails one being 5V analog and the other being being 5V Digital. So what is difference between those two(other being called digital and Analog)

Thanks

This is usually done to minimise noise ingress to the analog part from the digital part.