Vevor SDS1104 4 channel scope

[Demon]

Paid $256.99CAD+FreeShipping direct from Vevor.ca. Seems to be a clone of the Owon SDS1104 (best price I can see is $318+shipping+taxes on Banggood).




Played with it with a rotary encoder. It didn't take me long to be able to do single scan and auto.

- The USB cable cannot connect to PC, it has a USB type B connector (waiting for USB-A cable from amazon)
- PC software seems to be only for display, there doesn't seem to be any feature to tweak the graphs.

I really do like having 4 channels; all 4 probes are included. I will be able to scan an encoder, and check a pulse from PIC to see how fast I can check encoder pulses.


Turning the encoder at normal speeds looks like this:




It doesn't have protocol decoders (I2C, SPI, USART, etc), but I wasn't looking for that on a bargain scope. And I really needed the scope now to help figure debounce circuits.

[Demon]

(couldn't post all links in first post due to limit)


Turning it really fast and increasing scan speed has some attempts looking like these:

500uS




200uS

[Demon]

The weird thing, it that the voltage can go above 5V and below 0V when I turn the encoder real fast.

I'm using USB voltage from the PC, so no idea how that happens. Maybe the scope loses it's place and drifts beyond the actual limits; I'm not knowledgeable enough to determine, and reviews are few.


EDIT: Argh, I'm probing an RC circuit. Voltage rises as capacitor charges, lowers as it discharges...

[Demon]

There's something hinky going on. Sometimes it won't scan the probes. I still haven't figured out what exactly.

But I go though the MODES, eventually the RUN/STOP buttons goes red, I reset it back to green, and all is well.

It could just as easily be me doing something wrong.


I'm getting quickly used to using the colour codes on the probes; real handy feature when using multiple probes.

Side note, I really like the scope. Playing with 2 probes on EC11 rotary encoder and 3rd probe on RV17 potentiometer with switch.

[HenrikOlsson]

If you don't know, read up on what Auto/Normal/Single mode actually does. Also, there's no indication of trigger level on the scope screen, where do you have that set?

[Demon]

I have it set at 4.9V along the right edge of the screen. That's exactly the thing that I haven't totally figured out yet. Sometimes it's there, sometimes it's not.

When nothing displays, I adjust it down, fiddle through the modes, and eventually it shows up. Could be the scope, could be me.


From what I've observed:

- AUTO is constantly scanning, RUN/STOP button locks display when needed,
- NORMAL locks display until next trigger,
- SINGLE locks display, RUN/STOP button resets.

The annoying thing with SINGLE, is that the scope reverts to AUTO after I reset RUN/STOP. Then I have to cycle through the modes to put it back in SINGLE (takes a few button clicks each time).


I like to learn as mush as I can on my own, then read up when I have specific questions (like now I'm going to read up on auto, normal, single modes, as well as when does voltage trigger level appear on the screen).