** Normally, frequency stability relates to the internal temperature of a
generator - so frequency stability = temperature stability. If the
frequency varies independently of temperature, then there is something wrong
like a faulty frequency control pot.

In any case, the tempco of a carbon track pot ( as used in the 3312a) is way
higher than metal film resistors and film capacitors.

How bad is your unit's stability ?

If ( after a 1 hour warm up ) you set the gene at 10kHz and waited 30
minutes - what would the new frequency be?




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.

Tried to lubricate potentiometers and switches with no success.

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