Ok, so looking at the comparison, the 4227 has higher bandwidth or sampling rate and supports an external trigger and AWG. Which spec "kills" support for the new graphing frequency counter? The items shown in the "comparison" make no sense to me as far as differences that would make it not support the new feature. What am I missing?
The 4223, 4224, 4423 and 4424 are from the same immediate family and have a frequency counter built into the hardware, the 4227 although part of the generic 4000 series does not have this hardware support.
It is not currently mentioned in the specifications, it is a new feature that has only recently been added to these particular devices. At present it is only referenced in the new features list that you have already seen, and this applies to the beta releases of the software. The specifications and supporting documentation will be updated soon.
Does this mean that earlier hardware versions of the 4223,4224, etc did not have the hardware frequency counter or have they always had the hardware but the software is just now catching up?
Earlier versions of these scopes didn't have the frequency counter however the firmware can be upgraded to support this feature. It may be added to other scopes in the future although I have no timescales for this or details of which scopes will support it.
tomfield wrote:Does this mean that earlier hardware versions of the 4223,4224, etc did not have the hardware frequency counter or have they always had the hardware but the software is just now catching up?
Hi Tom,
Sorry if this gets a bit complicated.
In the R6.6 beta release of the software there is an option to plot frequency vs time for all versions of PicoScope. This is available via the maths channels.
The PicoScope 4223/4224/4423/4424 also now have a hardware based frequency counter where you can dedicate a channel to frequency measurement. This hardware based frequency counter is within the FPGA and was also from the new software. There is no hardware change made for this - once the software is upgraded this new functionality is added.
For most applications the software based approach is best as you can record a waveform and plot the change in frequency of that waveform using a single channel. If you use the hardware based frequency counter you have to dedicate a channel to frequency measurement. The situation where the hardware based approach works best is where you want to plot for a long time (eg 1000 seconds) the frequency of a fast signal (eg 10MHz), this would not be possible with the software based approach as you would need to record the 10MHz signal for the whole 100 seconds (to record the 10MHz signal you might sample at say 50MHz for the 1000 seconds, that would require at least 50Gbytes of data).
OK, so now after much explanation, it appears that (for version 6.6.x) there is both a software frequency plotting option for all Picoscopes (which I did not see in the beta release notes) as well as a hardware/firmware update to the 4223 series.
Examining the release notes again, I see that Frequency is mentioned under new math functions. This must be the software frequency graphing function mentioned above.
My software version is 6.5.? , so I have not seen the "software" version yet.
You say that the new frequency plot function is available in the math functions. Could you expand on that a bit, so I know what to look for when I upgrade. I believe that I saw that both the beta version and the production version can be installed at the same time.