PS503/Repairs: Difference between revisions

From TekWiki
Jump to navigation Jump to search
No edit summary
No edit summary
Line 1: Line 1:
* [https://www.youtube.com/watch?v=h5ZH7e3sXbo Tektronix PS503A Power Supply Restoration] by NFM @ YouTube
* [https://www.youtube.com/watch?v=h5ZH7e3sXbo Tektronix PS503A Power Supply Restoration] by NFM @ YouTube
==PS503A: Instable Output/Output voltage is decreasing with time==
The output is instable (±100 mV) and is decreasing with time.
The faulty part was C34 (4.7 µF/50 V). C34 stabilises the reference voltage. Measuring C34 with an RLC-meter shows no fault: 5.0 µF and a serial resistance of 5 Ω. The faulty behaviour of C34 can only be seen by applying a DC voltage (see picture).
C34 is shorted by the output-on button. So, replacing C34 with a tantalum capacitor is not recommended.
==Pictures==
<gallery>
PS503A - Current C34.png|DC current thru C34 (12 V / 10 mA limit)
</gallery>


[[Category:Instrument repair reports]]
[[Category:Instrument repair reports]]

Revision as of 04:31, 21 February 2024


PS503A: Instable Output/Output voltage is decreasing with time

The output is instable (±100 mV) and is decreasing with time. The faulty part was C34 (4.7 µF/50 V). C34 stabilises the reference voltage. Measuring C34 with an RLC-meter shows no fault: 5.0 µF and a serial resistance of 5 Ω. The faulty behaviour of C34 can only be seen by applying a DC voltage (see picture).

C34 is shorted by the output-on button. So, replacing C34 with a tantalum capacitor is not recommended.


Pictures