TEK 2245A Start-Up Problem

[JdaleH]

When I press the on/off switch, most of the time the unit will not start up.  I hear an ongoing click sound (relay?).  I can usually keep pushing the button and the unit will turn on.   Most aggravating.  Can it be fixed?

[Jeff eelcr]

Yes, sounds like a capacitor problem in the power supply as a guess but would require troubleshooting to the problem.
Start with service manual and multimeter at a minimum, capacitance checker may help.
Jeff 

[Jeff eelcr]

Did you mean Tektronix 2445A?
Jeff

[Vovk_Z]

When I press the on/off switch, most of the time the unit will not start up.  I hear an ongoing click sound (relay?).  I can usually keep pushing the button and the unit will turn on.   Most aggravating.  Can it be fixed?

Quite often that's a power supply problem (one or several dried electrolyte capacitors). The most efficient  way to troubleshoot it when you have in-circuit ESR meter.

[BlownUpCapacitor]

Go to PDF page 263 on the service manual here: https://w140.com/tekwiki/images/d/d1/070-7672-00.pdf
disconnect power supply output wires to completely isolate the PSU from the scope. If the 2245A uses PCB jumpers instead like traditional 22xx series scopes, desolder those. Measure voltages with a DMM and use a constant current load to measure the tripping current and make sure it matches up with the specs in the service manual.

If the PSU trips under loaded, trouble shoot the PSU. If the PSU works perfectly fine, trouble shoot the rest of the scope by disconnecting power to some parts of the scope and see what makes the PSU trip. Isolate the problem and troubleshoot the suspect board/board area.

Go to the Maintenance section of the manual and the sub section "Troubleshooting Techniques". Read that and then start your troubleshooting journey.