Using PCLab2000SE v4.04, PCGU1000 and PCSU1000, Win XP sp 3 32-bit…
I have found a curious behaviour when using the Circuit Analyzer, specifically that when using any range that passes through 1kHz the application is commanding the PCGU1000 to output 6kHz rather than 1kHz, when a 1kHz signal should be generated.
This glitch at 1kHz occurs when ever a frequency step of 1x or 5x is selected, when a step of 2x is selected it occurs at 1020kHz.
The DUT above was a simple RC filter, the phenomenon can also be observed with just an interconnect between the generator’s output and the 'scopes input.
It does not seem to occur at any other frequency, multiples of 10 or otherwise, here is a 100Hz to 1MHz sweep:
I had been running a 4.04 beta version with the install package dated July 7, 2011, that just installed is dated December 15, 2011–but that’s what beta testing is all about. I should have caught it sooner however I have been working with RF stuff for quite a while now.
As usual your quick responses and resolutions get better each time–how that is possible I do not know–but it’s true!
Hi I’ve got same behaviour with my just bought pcsgu250 and the software 1.10, driver version 1.0.0.2
While testing the impedance curve of a speaker, I heard a strange step, I first thought I heard a speaker anomaly, but I also saw this glitch at the curve. The during the test I looked sharp to the frequency steps and saw the faulty step.
I did some more tests, here is the output:
When I sweep from 100 Hz to 30kHz or 100kHz, when the step to 5 kHz must be made, from 4kHz to 5kHz, the generator outputs 10kHz, then it goes to 6kHz.
When I sweep from 10 Hz to 30kHz ro 100kHz, when the step from 400Hz to 500Hz has to be made the generator put’s out 1kHz, then it goes back to 600Hz.
When I sweep fom 1 Hz to 10 kHz, the step to 50 Hz gives 100 Hz at the generator before stepping to 60 Hz, and the step to 5kHz gives 10 kHz before going to 6 kHz
There are possible more glitches, but I didn’t check them all.
I checked the frequency with a frequency counter.
I created a picture, but I don’t know how to upload this.
Now the PCLab2000LT is updated to version 1.11.
Here is the link to download the software: velleman.eu/downloads/files/ … _setup.zip
Following modifications are made:
Bode plotter frequency setting bug fixed.
Big screen time bug at 0.1us/div and 0.2us/div fixed.
“Save/Recall Last Oscilloscope Settings” fixed and expanded.
Please uninstall the previous version before new install.
