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Resonance?

Chip;
  First, congratulations on your acquisition of the scope and signal
generator. In a very short while, you'll wonder how you ever got along
without 'em.

As far as your question about the resonance goes, yes, a rise in frequency
response, followed by a drop in response as frequency goes up, usually
indicates a resonance. The sharper the rise and drop, the higher the Q of
the resonance peak.

I have a concern about your description of your test circuit, which may
have a great effect on the meaningfullness of your observation. That is,
neither your original description, nor your clarification, make any mention
of a ground connection between the scope and the signal generator. Without
one, you can get all sorts of interesting (and meaningless) response curves,
as your scope and signal generator find their own bizarre return ground
path, and that unpredictable path ends up becoming part of the circuit that
you're measuring, rather than a nice, stable reference point.

As to a different query about other harmonics in a square wave, such a signal
will contain the primary frequency and odd harmonics. That is, a 1 KHz wave
will also contain 3KHz, 5KHz, 7KHz, and so on. Fortunately, the magnitude
of each sucessive harmonic is less than the previous one, with the largest
percentage being that of the primary frequency.

Wes B.