What exactly does "slow trip" mean?

Maybe. Depends on what the LED is signifying. If it's just the power LED, and doesn't serve any secondary engineering diagnostic function, then it could definitely signify that the power supply is cycling up and tripping out repeatedly. This will often be accompanied by a soft 'ticking' noise.

Arfa

The power supply may be in a failed condition, or there is a short somewhere in the set. This would require proper troubleshooting, and not guess work.

Take the set in for a proper estimate. It can be a challange for even a skilled service tech to repair these types of faults.

Jerry G. ======

It sounds as though you might be talking about a circuit-breaker, designed to "trip" only when a current overload has continued for a given number of milliseconds.

Given the age of the TV (at least 17 years) I can't really justify the expense. I'm prepared to spend my own time, though, in the hope that it will be a fairly inexpensive fix, once identified.

It would first be necessary to determine if the power supply was 'self-faulting', or tripping as a result of detecting an over-current condition on one of its rails. Without experience in the field, this may prove difficult for you to determine, as sometimes, trip conditions can be a little bit 'round and round in ever decreasing circles'.

Generally, self-faulting of the power supply is caused by faulty electrolytic caps - which may be open circuit, short circuit or poor ESR - short circuit secondary diodes, and occasionally more subtle problems in the feedback circuitry. Reasons for overload tripping include short circuit HOP transistor, faulty flyback transformer, faulty HV tuning caps, faulty E-W modulator circuitry, faulty field output chip, faulty sound output chip, bad joints in HOP stage and so on. To get any more specific help, you would need to declare the make and model number, and then someone on here might be able to point you at particular problems for that TV.

Also, I don't know what your experience level is, but if you are not used to working with TV sets, and switch mode power supplies in particular, please be very careful of your personal safety. These power supplies are connected

*directly* to incoming line power, and are potentially lethal, as in able to cause death.

Arfa

I'm glad you mentioned the field output chip - that seems to go at the rate of once every 6 years or so on this TV, having been replaced twice already. It's worth a punt, anyway.

Point noted.

Well, I replaced the field output chip and the voltage regulator and repaired two circuit board damaged connections in the vicinity of the latter and it works! Just goes to show you can be lucky even though you don't really know what you're doing. Thanks, Arfa.

You're welcome, and the good bit is that now you do know at least a little bit more about it, for when you next encounter a similar problem. Well done on sorting it !

Arfa