James wrote:
In my study, my lamps will flicker every few minutes or so. I assume that
I have some defect in the wiring on this circuit, or that there is a problem
with my circuit breaker connection, or the breaker itself.

So, today I went to the breaker box and made sure that the wire connecting
to the breaker were screwed down as tight as possible. I was able to turn
the screw a full 1/2 turn, so I thought this might have cured the problem.
But, it didn't.

This is a 15 amp, 120 volt circuit, and breaker. Is it very likely that
the breaker itself is bad, or may I have a wiring problem somewhere in this
circuit ? As far as I know, it provides power to just my one room study.

I can tell that when I turn on a heavy-current device such as my fax
machine, these lights will flicker when the machine operates. So, the
flicker can be triggered with a heavy load. I have never noticed this
before. But be aware that I get frequent flickering even when there is no
extra heavy load.

The house is 30 years old, and most likely, it is the original breaker.

Groups trimmed; this really isn't construction query...

The first step at the panel was good idea -- as another has already
said, check next at the outlet(s) directly affected. "Backstab"
terminations are, in fact, notorious for such symptoms developing and
yours are about the right age both to have possibly used them and for
problems to show up.

I'll add a little more...

First, by "lamps" are you talking wall-outlet plug-in or a ceiling
fixture(s)? One assumes probably the former but ya' never know...

It would seem somewhat surprising this is the only room on a
circuit--might want to check that for certain by doing a load survey of
what isn't available when this breaker is off. Often there will be a
scattering of service on a single breaker in order to ensure not all in
one area of a house goes off if that breaker trips--that may be fooling
you here and the real problem could be in another connection elsewhere.

If the flickering under load is indeed a new symptom, that does indicate
something has changed and loading of the circuit is indicated by this.
It could be that a loose connection as hypothesized has built up enough
additional resistance that it's now showing up noticeably.

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