54622D curiosity about horizontal trace  - Page 1
Forum section: electronics / repair

author: Hrvoje_CRO
author_rank: Regular Contributor
timestamp: November 01, 2020, 07:06:17 pm
content: Hello everyone!Well i have maybe silly concern about this:I have 2 54622D scopes. I have noticed something which makes me curious and concerned a bit.Is it normal to see a noissy horizontal trace when the scope is powered up, with horizontal trace set exactly to 0V, but after some short time it becomes solid horizontal line?I have noticed this on both scopes, on one's is that behaviour on channel 1, and on other scope on channel 2. Both channels are set at 5V.That initial noise is like here in Dave's videohttps://youtu.be/aVNfFewFn_Y?t=121if you look at the ch1.Thanks!Hrvoje

author: Hrvoje_CRO
author_rank: Regular Contributor
timestamp: November 02, 2020, 02:44:15 pm
content: Any 54622D users here?Thank you!Hrvoje

author: oPossum
author_rank: Super Contributor
timestamp: November 02, 2020, 04:11:12 pm
content: What is your V/div setting? The 54622 has quite a bit of visible noise at 1 mV/div. Mine did not seem to change after about an hour at 1 mV/div.

author: Hrvoje_CRO
author_rank: Regular Contributor
timestamp: November 02, 2020, 04:51:12 pm
content: Hello,Mine V/Div setting is 5v. The horizontal trace is set to 0V.See a video:https://easyupload.io/0r9edvYou can see at first channel 1 how steady trace is, and as i switch to ch2 you can see the noise which got stable after some time.Same thing i have on both 54622D.Thank you for your reply and btw., sorry for shaky video.Regards,Hrvoje

author: SilverSolder
author_rank: Super Contributor
timestamp: November 02, 2020, 05:39:23 pm
content: Mine shows the "non noisy" line immediately on start, both channels.I noticed this in your video:The 54622D has a battery inside which needs to be in good condition to store calibration data. The first thing you should try is to replace that battery, then run User Calibration.

author: Hrvoje_CRO
author_rank: Regular Contributor
timestamp: November 02, 2020, 06:01:06 pm
content: Hi,Yes, on on of the scope the battery should be replaced. Regarding noisy line, in my case it is on both scopes. On one is battery ok.Regards,Hrvoje

author: SilverSolder
author_rank: Super Contributor
timestamp: November 02, 2020, 06:03:35 pm
content: Have you tried running the User Calibration on the scope with the good battery? (Remember to let it warm up thoroughly first...)

author: Hrvoje_CRO
author_rank: Regular Contributor
timestamp: November 02, 2020, 06:07:05 pm
content: I will try that.Have you tried to test your scope with exact same settings as i did have?Thank you!

author: SilverSolder
author_rank: Super Contributor
timestamp: November 02, 2020, 06:32:35 pm
content: Yes, I used the same settings.You know, it probably isn't a problem at all.The specifications for this scope are only valid after a 30-minute warm-up period (see manual). If there are no other symptoms or problems, you are more than likely witnessing behaviour that is acceptable for the first few minutes after start-up.I have many instruments that take a lot longer to warm up than that!

author: Hrvoje_CRO
author_rank: Regular Contributor
timestamp: November 02, 2020, 06:39:44 pm
content: My friend,The both scopes are working normally. Even that one with low battery.But i am so nitpicky that even slight "anomaly" makes me concerned.I have 34410A multimeter which has a bug that even engineers from Keysight have no idea what's wrong. Look here:https://community.keysight.com/thread/37599.I am typical young player in EE, but perfectionistic as f*ck. Sorry for that. Usually i am politeBest Regards,Hrvoje

author: SilverSolder
author_rank: Super Contributor
timestamp: November 02, 2020, 08:56:07 pm
content: No worries - I am a perfectionist too, but after many years of frustration, I have learned to apply perfectionism only where it matters!