Statements like "frequency stability is bad or poor will get you nowhere.
What are your requirements for stability?
Under what conditions? Temperature variability, time variability,
noise??? At what frequency?

My requirements are fairly modest. Just to tune HF receivers and their IF
chains. Say from 200 kHz to 10 MHz. Noise and temperature is not an issue
for my case.

What is the stability you are MEASURING?

Frequency measurement results:

- Just turned on. Frequency = 5.000 MHz Delta F = 0
- 15 minutes after. Delta F = -98 kHz (drift = 6.5 kHz per minute)
- 30 minutes after. Delta F = - 116 kHz (drift = 3.7 kHz per minute)
- 45 minutes after. Delta F = -132 kHz (drift = 2.9 kHz per minute)
- 60 minutes after. Delta F = -141 kHz (drift = 2.3 kHz per minute)
- 75 minutes after. Delta F = -147 kHz (drift = 2.0 kHz per minute)

Drift is too high for any practical use.

What is the stability spec of the generator?
Stability is a NUMBER, not a vague statement of dissatisfaction.

Tell HP. They do not mention frequency stability in the manual and no useful
information can be found on the web.

HP equipment of that vintage was typically near the better end of
performance for equipment of that vintage. But even HP equipment breaks.
Performance is usually better near the top end of the dial.
Just 'cause you can get 1000:1 range on the knob doesn't mean
you should.

This is just I what I would to like to know: which is people experience with
non-HP generators using an analog frequency-generation circuit.

OK, I looked up the spec. I can't find any reference in the spec
to frequency stability, other than it takes an hour for the frequency
to get within 5% of the dial setting.
That oughta tell you something.

Well, that figure is also related to dial accuracy, but can serve to broadly
figure out frequency stability.

In general, if your requirements contain the word "stability",
a function generator is a poor choice.

I know, but if they produce them, they evidently serve to do something. In
my case there is nothing I can do with such a poor generator. And that is
HP! Again my question is: is my generator faulty or all
instruments based on the same (analog) frequency generation principle
(charging a capacitor at constant current) behave more or less the same?

Regards.

Tony