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I’ve just recorded this video. You will notice that every time I change the display amplitude the Signalhound takes a long time to settle. Is this expected or does it indicate that something is faulty? I am using RBW of 30kHz and VBW of 3kHz.
See attached file
This is a .bbr file renamed .bbk
Oh well, what you could see was that every time I changed the amplitude setting by 2dB the signal dropped down the screen over about 10 seconds by 10 dB. Then I changed the setting again by 2dB and the signal went to the top of the screen again, 10dB higher and then dropped down to where it was.
The Signalhound seems to need a d.c. path on the input. My amplifier design has an output attenuator and has worked fine; I was testing a Miteq amplifier when I obtained the strange result. I put a 3dB pad in the way and it was fine.
Eduk,
We have observed, when the preamp is used, at 0 dB of attenuation, it can take a long time for the DC blocking cap to reach steady state (up to 30 seconds). Typically, setting your reference level to -30 dBm briefly (preamp on, attenuator 5-10 dB), before proceeding to maximum sensitivity, allows quick settling.On a fraction of units, the preamp’s DC blocking cap never reaches steady state without a better DC path to ground. We typically have to add a 2.2k resistor to help bleed this off. You can contact us for a warranty repair if your SA44B is exhibiting this behavior. I apologize for the inconvenience.
We will be updating the design to add this resistor in the near future.
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