EEVblog Electronics Community Forum

EEVblog => EEVblog Specific => Topic started by: Dr Wobble on April 20, 2017, 01:27:21 pm

Title: EEVblog #987 - Keysight U1272A Multimeter EMC Followup - Not available.
Post by: Dr Wobble on April 20, 2017, 01:27:21 pm
Got an email today saying Dave has just uploaded a video. Clicked link, video unavailable. Could be me doing something daft but don't thinks so. thought I'd let you know Dave.

Secondly, Dave seems a bit all over the shop recently, I was hoping this video would be himself getting back on form.

Best regards, Andy.

PS, Utube said they were sorry. Have they got the knives out for EEVblog
Title: Re: EEVblog #987 - Keysight U1272A Multimeter EMC Followup - Not available.
Post by: jpc on April 20, 2017, 01:30:29 pm
Yeah, same here and was about to post when I saw your post.
Title: Re: EEVblog #987 - Keysight U1272A Multimeter EMC Followup - Not available.
Post by: Dr Wobble on April 20, 2017, 01:32:59 pm
Not just me then. Perhaps he uploaded it and wanted to edit it, so had to delete it.

A.
Title: Re: EEVblog #987 - Keysight U1272A Multimeter EMC Followup - Not available.
Post by: jpc on April 20, 2017, 01:36:03 pm
Nope, not just you, I even checked all three channels just in case.
Title: Re: EEVblog #987 - Keysight U1272A Multimeter EMC Followup - Not available.
Post by: bktemp on April 20, 2017, 02:01:32 pm
It was there, but it is gone now.
Maybe Dave found another difference between the old and the new revision he missed in the video? Like JP1 connecting the mainboard to the input terminals.
Title: Re: EEVblog #987 - Keysight U1272A Multimeter EMC Followup - Not available.
Post by: FOObar on April 20, 2017, 02:32:22 pm
Raises hand, I have the same problem.

EEVblog #987 - Keysight U1272A Multimeter EMC Followup
3 hours ago.

:\

I hope this hasn't anything to do with YouTubes descision to block his "EEVBlog Discover(y)" channel.
Title: Re: EEVblog #987 - Keysight U1272A Multimeter EMC Followup - Not available.
Post by: jancumps on April 20, 2017, 02:44:57 pm
Quote
Dave seems a bit all over the shop recently, ...

All over the shop with high quality. 3 excellent videos full of science in a few days...
Title: Re: EEVblog #987 - Keysight U1272A Multimeter EMC Followup - Not available.
Post by: elliottveares on April 20, 2017, 03:23:29 pm
Same to here in the UK, I just get "This video is unavailable."

Quote
I hope this hasn't anything to do with YouTubes descision to block his "EEVBlog Discover(y)" channel.

Me to!

I have however found a cached copy on yahoo though and since downloaded it to my computer.  ;D Would share a link to my download of it on here, but I think that would activate the ban hammer.
Title: Re: EEVblog #987 - Keysight U1272A Multimeter EMC Followup - Not available.
Post by: FOObar on April 20, 2017, 04:13:08 pm
DM me the URL, i don't care about the posibility of being banned.
Title: Re: EEVblog #987 - Keysight U1272A Multimeter EMC Followup - Not available.
Post by: Bud on April 20, 2017, 04:17:16 pm
Secondly, Dave seems a bit all over the shop recently

I am of same opinion and honestly it worries me.
Title: Re: EEVblog #987 - Keysight U1272A Multimeter EMC Followup - Not available.
Post by: FOObar on April 20, 2017, 04:56:50 pm
For those playing at home, check this link https://we.tl/jOnpZZX9MW (https://we.tl/jOnpZZX9MW)  [This link works until 26 April 2017]
Title: Re: EEVblog #987 - Keysight U1272A Multimeter EMC Followup - Not available.
Post by: lunecat on April 20, 2017, 05:03:50 pm

I hope this hasn't anything to do with YouTubes descision to block his "EEVBlog Discover(y)" channel.

That crossed my mind too! Especially since the last EEVBlog video 986 was posted before the trouble with the Disco channel.
Title: Re: EEVblog #987 - Keysight U1272A Multimeter EMC Followup - Not available.
Post by: Dr Wobble on April 20, 2017, 05:13:51 pm
"All over the shop with high quality. 3 excellent videos full of science in a few days..."

The logic video was good, didn't see the Voyager video's.

I wasn't disparaging his work, more commenting on the general vibe. He seems a bit wired. Understandable what with Utube playing silly buggers.

A.
Title: Re: EEVblog #987 - Keysight U1272A Multimeter EMC Followup - Not available.
Post by: timgiles on April 20, 2017, 05:48:34 pm
Thanks FB - interesting to see the changes made. I wonder if anyone with a more recent one can crack it open to confirm if the Rev 6 (or 5) board is just a natural minor update to the PCB. I also wondered if Dave could try replacing the resistor and testing it (on his older meter) and then change the two Ferrites again to see the impact of the two noticed alterations.
Title: Re: EEVblog #987 - Keysight U1272A Multimeter EMC Followup - Not available.
Post by: TheAmmoniacal on April 20, 2017, 06:23:22 pm
Just in case you didn't see it, another difference:

Someone should note all changes and the new part values, see if we can fix our existing meters!
Title: Re: EEVblog #987 - Keysight U1272A Multimeter EMC Followup - Not available.
Post by: majenko on April 20, 2017, 06:26:19 pm
I'm guessing Dave is annotating it with corrections and adding an addendum to the end after I and others that came after me pointed out he mistook 0R links for ferrite beads. Where's his head at these days? Maybe a holiday is in order....
Title: Re: EEVblog #987 - Keysight U1272A Multimeter EMC Followup - Not available.
Post by: Monkeh on April 20, 2017, 06:28:56 pm
Just in case you didn't see it, another difference:

Someone should note all changes and the new part values, see if we can fix our existing meters!

That looks like just a supplier change (some tants are black, some are orange..). E: Oh yeah, they're drawing the eye away.. bodged in a different size resistor there.

It looks to me like the biggest change is the removal of two series ferrites between 'different' grounds in the meter. The 'new ferrites' look to me like 0-ohm jumpers. Split grounds: Usually not as smart as you think!

There's also that resistor value change, and a diode appeared further up the board (existing footprint, unpopulated in the older meter).
Title: Re: EEVblog #987 - Keysight U1272A Multimeter EMC Followup - Not available.
Post by: majenko on April 20, 2017, 06:35:39 pm
The change in tants may have been for a different ESR...? Unlikely though.
Title: Re: EEVblog #987 - Keysight U1272A Multimeter EMC Followup - Not available.
Post by: ggchab on April 21, 2017, 08:17:26 am
Also another visible difference:
Title: Re: EEVblog #987 - Keysight U1272A Multimeter EMC Followup - Not available.
Post by: cengland0 on April 21, 2017, 09:30:33 am
Another minor but visible difference.
Title: Re: EEVblog #987 - Keysight U1272A Multimeter EMC Followup - Not available.
Post by: JoeN on April 22, 2017, 04:53:20 am
Also another visible difference:

I noticed that too, and wanted to discuss it.  What would be the principle reason for making a track going from a fuse more narrow in a later rev?  I would have thought it would be the exact opposite, unless it is for some sort of emissions reason?  Or maybe this track is what is picking of the RF and resonating?

(https://www.eevblog.com/forum/blog/eevblog-987-keysight-u1272a-multimeter-emc-followup-not-available/?action=dlattach;attach=310013;image)
Title: Re: EEVblog #987 - Keysight U1272A Multimeter EMC Followup - Not available.
Post by: bktemp on April 22, 2017, 05:12:00 am
Maybe the reduction of the track width was necessary because of the additional JP4 next to JP1?
It would be interesting to see why they needed two addional pins going to the input terminals.
Title: Re: EEVblog #987 - Keysight U1272A Multimeter EMC Followup - Not available.
Post by: wraper on April 22, 2017, 07:49:44 am
Maybe the reduction of the track width was necessary because of the additional JP4 next to JP1?
It would be interesting to see why they needed two addional pins going to the input terminals.
Yes, in some point of time in between revisions on the video, they were shipping multimeters with a bodge wire between PCBs. IIRC that was to pass updated Canadian safety tests which could blow a small track on transient applied.