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Products => Test Equipment => Topic started by: bestel on April 23, 2021, 02:52:22 pm

Title: Brand new Keysight 1204G glitches??
Post by: bestel on April 23, 2021, 02:52:22 pm
 I've bought a Keysight 1204G.

Channel 1 and 2 are doing strange things below 250 MSa/S, with random glitches of only one point :

Maybe I'm just missing something but I'm thinking of a hardware fault.
(I've updated the firmware).

I've put some screenshot:
- Glitches on CH2
- No Glitches if I turn on CH3 + CH4
- Zoom of one glitch (there is always one glitch at a time)

I've also noticed that it seems there is no glitch in segmented memory mode.

 :'(
Title: Re: Brand new Keysight 1204G glitches??
Post by: bestel on April 23, 2021, 04:32:42 pm
This is the weirdest thing I ever saw  :o

Maybe it's the ADC (but it's a strange distribution over the time base), or maybe it's a memory corruption.
I think it's a memory corruption because it will explain why the glitches are not triggerable.
But it does not explain why these glitches occurs only on CH1 and CH2, and only below 250MSa/s.

I'm going to perform a firmware upgrade one more time, and maybe a firmware downgrade if it's still not ok.
Title: Re: Brand new Keysight 1204G glitches??
Post by: bestel on April 23, 2021, 05:12:51 pm
Firmware update did not change anything, and I can't find the 2.10 previous version.

The glitches occurrences changes from rare (0.05%) to more often (25%) regarding of the position of the reference.
For example, ref at -3 div = 0.05% of failures, at -2.5 div = 25%.

Does anyone have any idea of what's going on?
(As part as : sent it back for warranty ;D )
Title: Re: Brand new Keysight 1204G glitches??
Post by: bestel on April 23, 2021, 08:01:05 pm
Mhhhhhh I've put a DC signal, and I can trigger glitches by moving the references and/or the dc offset.

It seems to be a memory problem inside the ASIC :
- It does appear on segmented memory, but only once
- When at very low sample rate, it happen one time every two acquisition
- Only affect CH1 et CH2, but never at the same time

... But I can't figure out why it does not happen every time at the same place for every tension values.

It's under warranty so I guess there will be no problem and I won't even think about repairing myself, but it's a real hard problem and I kind like that.

Well, the thing the more valuable for the planet (and Keysight btw) should be "Keysight sending me only the ASIC part", as it's a tiny board inside it, but I think it will never happen  :-DD
Title: Re: Brand new Keysight 1204G glitches??
Post by: tv84 on April 23, 2021, 08:10:24 pm
v2.10 here (https://files.fm/u/zamhhu8qt).
Title: Re: Brand new Keysight 1204G glitches??
Post by: bestel on April 23, 2021, 08:27:00 pm
v2.10 here (https://files.fm/u/zamhhu8qt).

Thanks!
Title: Re: Brand new Keysight 1204G glitches??
Post by: bestel on April 24, 2021, 08:58:19 am
Nope, it seems to be hardware...

The only thing I do not explain, it's why this problem appear and disappear regarding of the voltage and/or position.
Title: Re: Brand new Keysight 1204G glitches??
Post by: bestel on May 11, 2021, 07:34:08 pm
Just to let you know, Keysight support is good, but rather SLOW |O

I contacted my reseller on April 24.
I was contacted by KeysightCare on April 28.
I received the "ok we will send you another one" on May 10.
But then I am still waiting for them...

Is this normal? Have you ever been confronted with KeysightCare?
Maybe I'm out of luck... twice :-//
Title: Re: Brand new Keysight 1204G glitches??
Post by: Neganur on May 11, 2021, 07:46:59 pm
Did you initiate the communication with Keysight or was there a 3rd party in between? (You mentioned reseller)

I’ve had good experience so far, but I had the email of a local contact who was very responsive. The logistics can be a bit slow though.
Title: Re: Brand new Keysight 1204G glitches??
Post by: bestel on May 11, 2021, 07:56:52 pm
I initiated communication with a third party... I think I should not next time...
Title: Re: Brand new Keysight 1204G glitches??
Post by: Keysight DanielBogdanoff on May 12, 2021, 05:11:50 am
I definitely recommend going straight to our support line for a situation like this - cuts out the middleperson. Third parties just come to us anyways. Calling the line is also a good option, but the email / webform should be equally fast.

Feel free to PM me the ticket # and the name of the person you're working with and I can check in on it.