Thanks 
Feel free to add some chapter here if like. I decided to check hardware first because if thats no good - little point to dig into software features. But luckily hardware is well engineered so software feature testing has green light.
I too am impressed with the hardware. I know a lot of people gripe about the pricing when compared to some of the low budget standalone scopes, but I find the UI much easier to navigate on the PC, and good quality is something that tends to cost a bit more.
Here are some of my notes when testing the 2205A and 2207B. I was originally looking only at a 2CH model, so I don't talk about the 4CH/MSO's here:
The 2200 series might as well be two different series because you have the A models (2204A=10 MHz, 2205A=25 MHz) and you have the B models (2206B=50 MHz, 2207B=70 MHz, 2208B=100 MHz). Interestingly, it looks in the pictures like the B models are in a larger enclosure, but they are actually using the same enclosure with the connectors on the long side instead of the short side! The A models and B models also differ quite a bit in terms of features, but they also differ in terms of price!
I went with the 2207B originally because it has the 1GS/s sample rate I really wanted. Had I been looking at the 4 channel ones, I might have noticed which I had missed until now and that is that th 2406B also has the 1GS/s sample rate at 50 MHz for 4 channels. This is the one I was set on ordering yesterday, but after the eevblog discount at tequipment, I pushed it up to the 2407B so I could get the nicer probes like the 2207B came with.
2207B bandwidth testing: I connected my Siglent SDG2082X (upgraded to 120 Mhz) to channel A of the picoscope with a 50 ohm cable and a 50 ohm passthrough terminator. The 2200 series does NOT have a 50 ohm termination option, but I think some of Pico's other models do. Here is a list of the peak to peak measurements from 10 to 120 MHz: 10=990mV, 20=970mV, 30=947mV, 40=917mV, 50=888mV, 60=854mV, 70=822mV, 80=801mV, 90=792mV, 100=783mV, 110=777mV, 120=762mV. I can't go any higher than 120 Mhz and it is still above the -3 dB point of 707mV! I then connected it up to the fast edge signal coming out of a DS4014 and measured rise/fall times of 1.81 nS on CH A and 1.87 nS on CH B, so around 190 Mhz using the 350/x formula. I also tested the SDG2082X 120 Mhz signal through the 10X supplied probes and it was 738 mV with the probes, still above -3 dB. The probe fall time on the fast edge was 1.1 nS. All of this was very impressive given it is only rated for 70 Mhz!
2205A bandwidth testing: Same connections and before, SDG2082X to channel A with 50 ohm cable/50 ohm passthrough terminator. Here is a list of peak to peaks measurements from 5 to 45 MHz: 5=1000mV, 10=988mV, 15=970mV, 20=933mV, 25=893mV, 30=866mV, 35=826mV, 40=720mV, 45=699mV. The fast edge rise time from the DS4014 is 6.9 nS on CH A, so around 51 MHz. I also tested the SDG2082X 120 Mhz signal using the 10X supplied probes and it got to 29 MHz before hitting the -3 dB point, not as exciting, but still better than specification. As the 2205A is available for sale without probes, I'd order it that way and get some nicer probes.
ONE BIG DISAPPOINTMENT:
The fast timebase you can set the 2205A to is 50 ns/div in regular triggering modes and 5 ns/div only in equivalent time sampling mode. In contrast, the 2207B allows you to go to 1 ns/div in regular modes, and in ETS mode to 50 ps/div. The issue here is that if you are viewing a 25 MHz waveform on the 2205A, you can't set the time base to see just one or two waves, you will see 12.5 cycles and can't choose a faster time base in any normal triggering modes. Watching a YouTube video someone posted about the 2204A, I can see that the 2204A only had 100 ns/div as an option! The datasheet says 5 ns, and it will be very lame if they come back and say that is for ETS mode only. It doesn't work that way on the 2207B and honestly if it had, it would have been going back. You can use the option at the top to widen the screen by 2x, 4x, etc, which seems to accomplish the same thing, but it really doesn't, because you are capturing more waves with less detail than if you could just choose the 5 ns/div that in the first place that datasheet specifies. I have brought this to Pico's attention and we've had a dialog back and forth about it, but it is still not resolved in the latest version of the software. I don't see a hardware reason why they can't do this, and it is in their spec, but who knows.
FEATURES:
Sample Memory: If you are just looking at waveforms, probably the 8k or 16k sample memory that comes with the 2204A/2205A is going to get the job done. The B models with megabytes of sample memory give extra options and capability. First, you can capture a waveform and zoom into it and still have detail. This is more beneficial at slower timebases where you aren't already pushing the sample rate to the maximum. Another thing you can do is use the rapid triggering mode which works like segmented memory on desktop scopes. It can capture X number of waveforms back to back with X amount of sample memory for each waveform which is very cool. You can step through them one by one and zoom into them as needed to look at detail. Another benefit of larger sample memory is for the decoding features because you can capture many packets, again each with enough samples to decode them properly, and then review/decode them. One nice thing is that the software still has a waveform buffer that can capture/review multiple waveforms even if you have an A model - the difference is that they aren't captured immediately after each other, but captured as they are brought to the PC. I admit I underestimated the value of the extra memory, during use it has proven much more useful than I thought in various conditions.
MSO: My units do not have the MSO feature, but I did test decoding some UART using an analog channel and it worked fine. Like most desktop scopes, it will handle decoding by using segmented memory or capturing multiple triggered waveforms. You then step through those waveforms and it decodes each one. It is important therefore to select a timebase that allows an entire packet of what you are trying to capture to fit in a single waveform capture. Again a plus is that decoding of 17 types is included at no extra charge. If this feature is important to you, I would heavily recommend the B models and perhaps even one of the MSO models. The reason for the B is because it won't miss any of your packets using segmented/rapid triggering mode. One of my tests was setting up a microcontroller that output a line of text every 100 mS. Rapid mode catches them all as expected, but relying on the waveform buffer to capture them (all you have on the A models) meant there were missed ones because it didn't trigger fast enough. It is a personal thing, but I prefer the way Saleae handles captures by doing a single trigger and then one long waveform you can scroll around in. This style might be better if you need to trigger on each event.
USB: The device is a USB 2 device which concerned me a little bit, but I didn't find it to be slow or laggy at all. Even when I told it to capture a lot of waveforms using the segmented (rapid) mode, it still seemed very fast. I think Pico's 3000 series offers USB 3 if that is important to you. I've had some devices with USB 3 that are bit more sensitive than I'd like in terms of cable length and signal integrity so I'm perfectly fine with USB 2 as long as it performs well, and it seems to.
Power Usage: The 2207B used 10mA when plugged in, but not connected to the software. It then goes to 450mA when in 500MS mode and 480mA in 1GS mode. The 2205A used 40mA when plugged in, but not connected to the software. It then goes to 420mA when in 200MS mode and 360mA when in 100MS mode. The thing to keep in mind here is that it never lowers the power if you are in the picoscope software - doesn't matter if it is running or stopped. They have a power management in the software, but it doesn't seem to reduce power management of the device, but rather is about the CPU consumption of the PC.
AWG: The AWG is a nice extra if you don't already have one. The good is that it has almost a dozen or so waveforms, supports arbitrary waves, and is included in the units at on extra charge. The downside is that for the A models, it is limited to 100 kHz, and for the B models, it is limited to 1 Mhz. All models only have a 2V peak to peak amplitude and 600 ohm output impedance. The B models also have a trigger capability in their AWG.
DC Offset: While I am pleased with the fact that the 50/70/100 B models do have this capability, the way it is implemented in the software greatly disappointed me. On a normal scope you just adjust the vertical to get the signal where you want it, but adjusting that in the pico software is really just changing your view or zoom. You aren't moving the signal in or out of the best ADC measurement zone by doing that. That is where the DC analog offset steps in and allows you to. The problem is that it is implemented in such as way as to change the incoming signal, but not reflect that change in the voltage reported or measurements reported. If that wasn't bad enough, it doesn't even indicate that this feature is enabled (and altering) the signal anywhere even thought there is a perfect place in the view-properties to do it. I do understand the confusion between zooming/panning and this feature and wonder if that is why it has been implemented the way it has, but it just isn't right. I always want to see the legend and the measurements reflect the actual signal, not the signal plus an offset applied to it.
Software Low Pass Filter: The B models have a channel option for a software low pass filter, but the resolution enhancement feature on the A models can likely be used to accomplish a similar result. I do prefer the low pass though to the resolution enhancement.
No color coding: Most of Pico's other scopes have blue, red, green, and yellow color coding on the channels and it would have been nice to use along with the probe color markers on the unit itself, even if it is just a small colored box on top of the channel to know which probe goes with which channel instead of remembering blue first=CH A, red=CH B.
SOFTWARE:
Their software is shared all across their test and measuring scope product line. The benefit here is especially good for their lower cost product line like the 2200 series because you get the advantage of the investment they make in the software all across their product line. It also means there will be continual updates as well which is nice. Nothing is worse than buying a piece of test equipment than finding that the company has moved on to a different model and no fixes or improvements will be made. While there are no guarantees, I read that their current version software still works with units that are 10-15 years old!
Software: It has a few modes you can use it in: Scope, persistence, or spectrum. The scope mode is both regular and X/Y and probably what you will use most. Persistence is meant to show changes between waveforms by using fading colors on a black background. I get what they are trying to do with it, but I really don't see myself using it. It certainly isn't the same as an intensity graduated display. The spectrum is a spectrum analzyer mode and I've played with it and it seems to work fine. I've read that you can change some of the parameters to larger numbers than typically found on a desktop scope, so that may make it more capable than many desktop scopes as far as the FFT goes. I'm going to focus mostly on the scope mode because it is the most important:
Buffer: It automatically keeps a buffer of recent waveforms that you can review or go back to. As mentioned above this is not the same thing as segmented/rapid triggering mode. That can also be used to feed the buffer if you need waveforms to be captured immediately after each other however on the 2206B and above models. You can configure how many waveforms to keep in the preferences. It is easy to navigate through them and find glitches, etc. For some reason, the number of buffers on the PC side is limited to the size of the capture, it even suggests this in help. I'm not sure why that is, but 8MS captures will only fit 5 buffers in memory, etc.
Zooming: Something that is extremely cool is that you can zoom into a signal without changing the time base - there is a separate zoom adjustment. I wish desktop scopes worked this way. The zoom features are amazing. You can zoom in or out, draw a box for zooming to a specific area, undo many zoom levels, and view the entire waveform very easily. It can even stay running while you stay zoomed showing you a small piece of the waveform in realtime as it runs. There is a zoom overview window that shows you where you in the overall waveform and you can move the zoomed area around easily and even resize it. This feature really sets it apart from desktop scopes because it is so flexible.
Channel Settings: You can select the probe (1X, 10X, custom ones you can create). There is also an area for resolution enhancement and low pass filtering. The low pass filtering might be for the 2206B and above, but honestly both resolution enhancement and low pass filtering seem to do a very similar thing it is just that you select one by enhanced resolution bits and the other by a low pass filter ceiling bandwidth. You can adjust the DC offset for scopes that support this feature (2206B and above). The axis scaling and position can be adjusted as well, and there is a zero offset channel feature which allows you to rezero a channel. One really cool thing is the Auto vertical setting. It will automatically choose the correct vertical based on the signal it is receiving so you don't have to fiddle with it to get it right. If you don't want it bouncing around, then you can set it to a specific vertical and it will stay. You can also choose DC or AC coupling.
Measurements: It has 18 measurements you can add to each channel and they can be for the entire waveform, between cursors, or for the cycle at a particular cursor. There are also cursors you can manually drag as you would typically expect as well and they also have phase cursors.
View Properties: Under the view menu is a view properties which opens a dialog at the right to show you the configuration and many properties of the scope state. It will tell you the sample interval, sample rate, number of samples, channel information for each channel, the state of the AWG, and capture information. This is worth keeping on screen all the time.
Triggering: The run/stop option is in the lower left corner along with the trigger options. The trigger can be none, auto, repeat, single, rapid, and ETS (channel A only for some reason). Rapid trigger mode is the segmented feature and you can tell it how many to capture. I tried 10000 and it worked very fast. You can set the trigger level, position, and time delay. Many desktop scopes no longer have the ETS feature, so it is nice to have it as an option here.
Other Goodies: It has a lot of flexibility in how you can configure the view and windows, putting a scope view in one and a spectrum view in another, or one channel in one and another channel in another. You can export bitmaps or the points as text. You can setup custom probes, math channels with functions, see reference waveforms, set alarms, create masks, or use a macro recorder.
Preferences: The preferences allow you to customize many of the features. You can change the waveform buffer amount, adjust the number of captures used in measurements, adjust the number of waveforms displayed per second, sin (x)/x settings, assign keys to almost any task (this is what allows people to make a rotary encoder type of board), etc.
FINAL THOUGHTS:
I love the 2207B I ordered. It does everything I want it to, I only wish it had color coded channels, but you can't have it all. I would like to see the software improve the way it handles the analog offset, but other than that I am happy with it.
I'm a little less excited about the 2204A/2205A because of the minimum timebase issue. I didn't love the probes so I would order it without the probes since there is an option to. They need to improve the 50 nS/div minimum timebase issue. I like the price for the capability you get though, you really can't go without having one in your bag...
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