I'm not following this precious 3ad for several months, now i'm the hurry to make some RF work and i have a straight question in order to decide what to do with this instrument (ie sell it for a siglent/rigol one)
Here's 100 kHz...30 MHz frequency response plots from unmodified Hantek 2032B with 1V output setting. Firmware version is 1.00.3.03.05 (150807.0). Calibration data is also untouched, original data from factory.
Results are measured with spectrum analyzer using trace max hold function.
First attached image includes three traces:
Green one is what you asked about: it's frequency response of automatic sweep from 100 kHz to 30 MHz from 2032B.
In the blue trace there's manual sweep with 50 kHz steps from 2032B. If we compare these two traces, we can notice that calibration data is not applied with automatic frequency sweep. Total amplitude error between 1 MHz and 30 MHz with frequency sweep was measured with delta marker and it was 2,09 dB.
Please note the notch at 24,6 MHz on manual sweep trace. At this point, relay clicked inside Hantek. Maybe some kind of output filter was disabled and/or the output impedance was changed because the level increased about 0,3 dB there. This relay is not clicking in automatic frequency sweep mode, even with very slow sweeps like 120 seconds.
In the red trace there's output from Marconi 2022C RF generator with -1 dBm setting and manual frequency sweep with 50 kHz steps. Those little 0,1...0,2 dB notches in this (and other) traces are spectrum analyzer calibration errors (this graph has 1 dB vertical scale while it's normally 10 dB so the spectum analyzer's frequency vs. level calibration table errors become also visible in this measurement setup).
If you plan to do any RF work, please consider to buy RF generator instead of any function generator. At least with Hantek, possibly with other ones also you will face some serious issues if you try to do RF work with it:
- General spectral purity problems and huge reference/spurious frequency leakage (please see my previous post)
- Insufficient frequency area for any kind of modern RF tuning. Suitable only for IF blocks testing.
- There's no dBm setting for the output - and the voltage setting does not correspond to any real world dBm in the "50 ohm. world" anyway! It shows correct voltage levels only against oscilloscope's 1 megaohm input, when spectrum analyzer and all other RF instruments have 50 ohm. impedance.
- You cannot generate any faint signals. With minimun setting the output is 2 mV. This is shown as -56 dBm at spectrum analyzer. This is too loud signal for any kind of receiver tuning etc. You will need external step attenuator to generate needed levels. With RF generator, you can go beyoud -100...-130 dBm depending on model. For example, most receiver tuning/testing tasks require usually less than -100 dBm signals.
- There's huge leakage from generator output also when the output is turned off! Output relay does not cut RF signals. Please see the second measurement, it's time domain level analysis when the 30 MHz output is first on with 1V level, then output turned off. The output relay has only ~56 dB attenuation at 30 MHz, so in the RF world it doesn't cut the signal at all...
If you want the generator to be silent you will also need to set the amplitude to the minimun value or turn of the whole generator. This leakage is frequency related; with 1 MHz the relay had 82 dB attenuation.
- Output connectors are BNC type, when all RF instruments have N type. If you use it with different kind of RF stuff you will need adapters.
I hope this helps.