Mini Oscilloscope

[uki]

What do you guys think about this, good choice?

http://www.miniware.com.cn/product/ds211-mini-oscilloscope-handheld-oscilloscope/

Manual, schematic, code:
http://www.minidso.com/forum.php?mod=viewthread&tid=1343

[shooter]

from the sales sheet it looks fine for here, I like the built-in sig-gen.
didn't notice probe spec's or connection type, you want standard bnc, not some automotive ribbon cable thing

[uki]

There are some pictures in the link, some show the probe but i dunno what type it is. The connections in the device are some mini type.

[PRR]

What is the price?

You can get very similar 'scopes, with less fancy or no case and power supply for $50. If what they show is a hundred bucks it is a fair deal.

The probe looks like some kind of mini/micro-"BNC" (not sure the right name). You find these hidden inside laptops and WiFis. You surely can buy the connector but there's many variations all too small for my eyes to ID.

You sure do not stick this sort of toy in a 400 Volt tube amp naked. This can be marginal even for full-size 1970s 'scopes. You can make-up an external pad.

[uki]

What is the price?

About $50 dollars.
https://pt.aliexpress.com/wholesale?trafficChannel=main&d=y&CatId=0&SearchText=ds211+oscilloscope&ltype=wholesale&SortType=price_asc&page=2&groupsort=1

You sure do not stick this sort of toy in a 400 Volt tube amp naked. This can be marginal even for full-size 1970s 'scopes. You can make-up an external pad.

It can only handle max 40v, I wouldn't go above 35 just in case.

[shooter]

It can only handle max 40v, I wouldn't go above 35 just in case.

pick up a 1x -10x probe(switchable), that gets you to 350-ish add a 100x probe for more fun.
the probe jacks are important, you don't want to be limited to the "companies store" for accessories

[PRR]

That link gives me an error; I think it is an expired Search.

I can never figure how to get a link into AliExpress. Even if I get the right page, they have many options.

This one is bare-bones but an exceptional bargain:

Aideepen Official Store
Digital Oscilloscope (Full assembled) + Acrylic Case + P6100 Probe for Arduino
Color:    Full assembled
US $18.80
https://www.aliexpress.com/item/2255799925418262.html (English, US$, to Maine USA)

The probe looks like standard BNC. (You "could" adapt a mini-BNC but that may be more time and labor than it is worth.)

[reidgw]

I just picked this up a few weeks ago. 20v max but the probe connector is a good old standard BNC. Not as fancy but it has decent enough features for $44

https://smile.amazon.com/dp/B073WVYK1X?psc=1&ref=ppx_yo2ov_dt_b_product_details

[uki]

Thanks for the tip PRR , I did order the one you suggested, I did like the price and the connector is BNC, that count as a plus, it also have more voltage limit!
Will take about a month to arrive thou, hopefully less !!

[uki]

Look what I've found on my stash!! Are these BNC connectors?

[sluckey]

I see 5 BNC Tees. The straight one could be part of a connector, or a terminator. Hard to say with just that one pic. Need to see both ends. Look for any writing on the barrel.

[uki]

The straight one could be part of a connector, or a terminator.

There is a label: Termination 50 Ohms

[sluckey]

The straight one could be part of a connector, or a terminator.

There is a label: Termination 50 Ohms

That's a very common terminator when you will use a 50Ω cable such as RG-58 to connect a scope into a 50Ω RF circuit. You would put a BNC Tee on the scope input with a 50Ω terminator on one side of the Tee and the RG-58 cable on the other side of the Tee. Then connect the other end of your RG-58 cable into the RF circuit under test. This properly terminates the cable into a 50Ω load at your otherwise very high input impedance of your scope.

No use at all in the guitar amp shop.

[PRR]

> Look what I've found on my stash!!

Remains of a 1990 computer "cheapernet" network?

That in-line Tee is very distinctive.

Instead of a garden-hose size coax around the building and "bee sting taps" drilled-in, cheapnet used lab-standard 52-ohm cable and fittings.

I know one installation that was still running satisfactorily in 2009. Entire academic office building concentrated to three 16-port twisted-pair hubs (not switches) bused on a single coax to the fiber converter. Because it was all un-switched, when Judy's net-card developed a jabber, most of the building stuttered to a stall.

All that stuff is about useless now.

[shooter]

All that stuff is about useless now.

had a small toolbox filled with every gender-convertor, adaptor, coupler, tee's.... Box full weighed 5lbs!
the empty box came in handy for orphan torx screws, only weighs about 2lbs, room to expand 

[uki]

It did arrive today! I just opened the package !

But the box not assembled as in the description and the p6100 probe is missing...

[shooter]

 
Quality help is hard to find these days.

[sluckey]

Should have included the probe. But here's a direct quote from the miniware link in your original message...

DS211 is an update style of DSO201, a pocket size digital storage oscilloscope fulfills basic electronic engineering requirements. It is equipped with 320*240 color display, Weighs only 65g! Portable Digital Oscilloscope DIY Kit provides waveform viewing.

I emphasized the phrase "DIY Kit".

[thetragichero]

> Look what I've found on my stash!!

Remains of a 1990 computer "cheapernet" network?

That in-line Tee is very distinctive.

Instead of a garden-hose size coax around the building and "bee sting taps" drilled-in, cheapnet used lab-standard 52-ohm cable and fittings.

I know one installation that was still running satisfactorily in 2009. Entire academic office building concentrated to three 16-port twisted-pair hubs (not switches) bused on a single coax to the fiber converter. Because it was all un-switched, when Judy's net-card developed a jabber, most of the building stuttered to a stall.

All that stuff is about useless now.

we had these running through my house growing up before the 'modern' stuff with cat5 (and before that house, we had a network that included the next door neighbor's house with the coax run through a garden hose). 10baset if i remember correctly

[PRR]

10base2

[uki]

Got the case assembled and the scope is working !
Now I just need to learn how to use it!

[DummyLoad]

> Look what I've found on my stash!!

Remains of a 1990 computer "cheapernet" network?

That in-line Tee is very distinctive.

Instead of a garden-hose size coax around the building and "bee sting taps" drilled-in, cheapnet used lab-standard 52-ohm cable and fittings.

I know one installation that was still running satisfactorily in 2009. Entire academic office building concentrated to three 16-port twisted-pair hubs (not switches) bused on a single coax to the fiber converter. Because it was all un-switched, when Judy's net-card developed a jabber, most of the building stuttered to a stall.

All that stuff is about useless now.

Ahhh! The good 'ol CSMA/CD half-duplex ethernet, it served us well - I still have a vampire tap tool and a couple of AUI vampire taps around here somewhere... That crap needed to go to Goodwill decades ago, if I can find it!

We still have the RG8 and AUI taps in my building, the building is getting the business end of a wrecking ball at the end of the year. Sad, the once beautiful red tiled roof building complete with gargoyle guardians erected in 1950 will be gone and replaced with a new Engineering Building sporting soulless modern architecture.

--Pete

[DummyLoad]

10base2

Thicknet was 10Base5; Thinnet is 10Base2; Twisted pair 10BaseT; 10Mb Ethernet/Fiber is FOIRL or 10Base-F. All the aforementioned are CSMA/CD technology - Aloha Bob M.! 

--Pete

[shooter]

Thicknet was 10Base5; Thinnet is 10Base2; Twisted pair 10BaseT;

you've ruined any chance of me sleeping peacefully 

[uki]

I been using a cheap power supply to power the scope, it does have the retification, one filter cap and voltage regulator, do I need a good filtered power supply for the scope?

[shooter]

how noisy is your display?
any "rippling" in the display?
is the trace nice and crisp or jagged?


if that's all good, the PS is probably fine, although you could probably use the scope to check the PS ripple, look for transient's...

[uki]

The trace isn't very crisp, it is a little jagged and there is some rippling.

Im using a signal generator from my cellphone 
here is the link for it: https://apkpure.com/function-generator/com.keuwl.functiongenerator

although you could probably use the scope to check the PS ripple, look for transient's...

What is transient's?

[sluckey]

That's probably about as good as that little scope can do. Even the text is ragged. Transients are things like switching noise, pops, etc. They usually look like big spikes in the display.

[PRR]

You are showing 30 milliVolts, a very small signal. You can play guitar at 30mV but it may be noisy.

What is it like with a shorted input? With a 1V input?

[uki]

What is it like with a shorted input? With a 1V input?

I did some tests today, and got some pictures.

• Tried another PS that is very well filtered but not much difference in the trace, at least not with the signal from the generator in the cellphone(noisy(picture on reply #26)), even with the chip and wifi disabled.

• Reading 1v ac from a transformer the trace was very clean.

Also I put the signal generator through my guitar onboard preamp(TLE2071 very low noise) and read the output, the IC did clean the signal a bit.

[gcwills]

The noise you see in the trace is a documented issue with the DSO138 and is due to digital noise getting into the analog circuits. Check out the forum on the maker's website (jyetech.com) for a fix involving lifting a couple of grounds that significantly reduces the noise issue.