Tektronix TDS544A failure

[a_alavi]

Hello all,

I received a 2nd hand TDS544A and when I power it up, I hear the fan turning on, and working, few collorful screens with no text, few random lines, and then a black screen with little circle and two hands (clock) in the top left of the screen and nothing after that...

I am ece graduate but not too hands-on... I appreciate if you could point me to anythink you might feel is the reason and how to debug this...

Much appreciate it,

a_alavi

 

[mister_rf]

I have attached here a user manual and the adjustment software for Tektronix TDS544A oscilloscope.
This is an old equipment so first need to check and test the power supply. Maybe it’s better to change some electrolytic capacitors in the power supply.

 

[a_alavi]

Much appreciate your answer...

I opened the scope and did basic inspection but could not find any obvious damage. Would there bw any hope we can find schematics/layout for this scope's circuitry? Just to have an idea for where to probe.

Thank you again

 

[mister_rf]

That's not a simple beginner task. :-D
Here we may have encounter a combination of multiple software & hardware problems, some related to loss of the stored adjustment information/corruption of the non-volatile RAM , others due to malfunction of the installed circuits/components. In order to fix the problems need to start replacing some electrolytic capacitors in the low voltage power supply, since a simple basic inspection doesn’t help always, their capacity diminishes over time. Later check the voltages and read on page 245 of the manual about troubleshooting procedures in order to determine faulty modules in the oscilloscope.
To help you in this matter need to have some additional details, for example pictures of the internal boards, display/screen messages, voltage values measured in the circuit.

 

[a_alavi]

Very insightful, sir!

I will work on this as I get some free time, and I will also share pictures on this thread... maybe with the information you share, and whatever I find, it could be helpful for others.

Best
a_alavi