Tektronix TDS 5XX Scope Owners and users - Please help! - Page 1
Forum section: electronics / testgear

author: bsgd
author_rank: Regular Contributor
timestamp: March 23, 2018, 10:03:29 pm
content: Hello all,So I recently got myself a used Tektronix TDS 544A Scope: 4 channels and 500Mhz Bandwidth. Problem is, I dont know if the scope is behaving the way it should... I will explain whats going on here. The scope powers on fine, but exhibits some weird beahivor IMO.I have found two issues:1- When I enter the UTILITY MENU and select DIAG - ALL TESTS and click EXECUTE, the scope just restarts normally, and does not show any test results. Its just as if I had turned it off and started it up again2- Everytime I power on the Scope its displays a message asking 'Re-use calibration data? Probe cal data exists for ch1 etc etc etc'. The message displays briefly and vanishes, asking if I want to keep or discard data. Thing is, no matter what I press, the scope does not recognize the button press and quickly moves on to displaying the welcome screen saying unit passed self tests. This happens every single time I turne the scope on.What I do know about the scope:1- It has lots of errors in the log. I opened it up and it has been recapped in the past, so I suppose someone fixed it but did not lear the log with a GPIB cable (I believe theres no other way to clear these errors).2- The DIP switches on the top board (A11 if Im not mistaken) are all closed as they are supposed to be from what I read.3- It measures waveforms just fine although I can only test high frequency signals tomorrow.Can someone who has used any TDS 5XX in the past help me?

author: Andy Watson
author_rank: Super Contributor
timestamp: March 23, 2018, 10:44:19 pm
content: What do you think is wrong with it?I have a 510A. I have just tried one of the self-diagnostics (of the processor) and it behaves as you described. It returns with the start-up screen and in that screen it says "power on check passed" (or similar). After a second it pops-up a a warning about "Re-use Probe Calibration data?" - it does this if it cannot find, or has detected that one or more of the probes has been changed since its last probe calibration.I think you have a functioning scope there

author: bsgd
author_rank: Regular Contributor
timestamp: March 23, 2018, 11:18:19 pm
content: Quote from: Andy Watson on March 23, 2018, 10:44:19 pmThanks Andy! Actually I thought after running the self test it would run some tests and show the results in a custom window instead of rebooting normally.Regarding the RE-USE Probe warning, does yours behave exaclty like mine? Right after reboot mine shows this message and requests if I want to keep or discard probe data for ch1. Thing is, if I try to press either the keep or discard buttons, it does not aknowledge the button press and skips right to the Welcome screen with the boot self test passed message.I dont have any probes attached to either channels. I just think it makes no sense to show me a warning and ask me to press a button to discard or keep the probe data since it does not aknowledge any button press and quickly jumps to the Welcome screen!I just wanna make sure its working fine since this thing wasnt cheap at all!Maybe it is normal behavior, I just want to know if yours behave exaclty like mine

author: Andy Watson
author_rank: Super Contributor
timestamp: March 24, 2018, 12:09:12 am
content: From the start:Power on:Screen goes through various contortions (mostly blank) reminiscent of its "self-diagnosis" test. This takes about 35 seconds during which time the front panel LEDs are all illuminated. A timer/watch symbol appears for a further 10 seconds.The screen fills with an image that looks like that last time the scope was used - this is immediately over-written with the "banner" image.The banner is is very quickly replaced with the pop-up about probe calibration "Re-use Probe Calibration data?" I press "OK use existing cal data".Now the banner screen returns and displays the options and "Power-On self check PASSED". - Use the Clear Menu button - and it's up and running.If instead of selecting "OK use existing  cal data", I press the "Erase probe cal" option, it does not produce the warning when next powered-up. It does the self-test and goes directly to the banner display.

author: Andy Watson
author_rank: Super Contributor
timestamp: March 24, 2018, 12:24:28 am
content: Quote from: bsgd on March 23, 2018, 11:18:19 pmI agree. However, (after some thought) it probably does most of those tests when it powers-up normally, then after performing the test it would have to re-configure all of its internal settings to a useful state - just as if it had powered-up. So my guess would be that Mr Tektronix programmed it that way, i.e. perform the requested test n-times then recover via its normal start-up routine.

author: bsgd
author_rank: Regular Contributor
timestamp: March 24, 2018, 01:07:07 am
content: Quote from: Andy Watson on March 24, 2018, 12:09:12 amMine behaves a little different, maybe its a firmware revision thing. It quickly goes to the "Power-On self check PASSED" so I dont have time to actually press the erase probe cal.I'll do some testing with some high frequency waveforms to make sure everyting else is fineThank you very much Andy!

author: Jwalling
author_rank: Unknown
timestamp: March 24, 2018, 09:48:08 am
content: Quote from: bsgd on March 24, 2018, 01:07:07 amRun the secure erase from the utility menu. That will erase everything that the previous owner had set, and put the scope back to factory defaults.

author: nctnico
author_rank: Super Contributor
timestamp: March 24, 2018, 11:06:13 am
content: If the copyright notice shown at startup is from before 1995 I'd replace all the electrolytic capacitors on the CPU, acquisition board, I/O interface board and the front panel.