Single Channel oscilloscope

[DSR]

I have a DiLOG DL9309 for when I want to do serious stuff and couple of cheap Chinese things that I tend to use most of the time. There are some stunning meters avaialble for under 20 quid but there's also some not so good. I've just bought a NENG620A - mainly because I was interested in what it was really like, no selector switch, just plug the leads in and it works out what you are doing and displays the result - I can plug it into the mains and read 240V then connect it across a resistor and not have to change settings or anything. Absolutley fantastic, measuring current I need to swap the red lead to a different socket but that's about it. All this for under 20 quid. Downside ? - won't measure anything under 0.5V or under 1mA.

As a general throw in the bag meter just in case you need it it's great but as a scientific instrument it could do better.

I've also recently acquired this :-

Which should have all the crusties on here shedding a tear

Next to it is the NENG 620A.

What you you rather have

 

[Ross365]

Horses for courses....it's so very nice to have them all . But if I could only have one multimeter, I'd have an analogue, but we are off topic.

 

[Robbie260]

Just looking at the Tpi 440 and both Uni t modules the Uni t UT81C definately comes out well ahead in the scopes capability. The Tpi dose is more industrial focused from what I can tell and there is some interesting optional acessories such milli amp clamps that go down to 10milli amps which really isn't quite low enough if it went down to 4 then it probably swing it for me and pressure sensor adaptors etc.

Uni t specs

Tpi specs

I suppose you could get away with 1Mhz on the scope with attenuators and other acessories. Sample rates a bit on the low side I comparison too both Uni t meters.

 

[eddie49]

DSR, I see your mint Avo 8 and raise you my GEC Selectest:

The Selectest was the Trimphone of Avos.

 

[Robotstar5]

Yes definitely getting a big brand name was thinking Kyritsu (Kewtech), Fluke or that French company that name totally escapes me.

Catu?

 

[Robbie260]

Catu?

Chauvin Arnoux was it.

 

[Robotstar5]

Chauvin Arnoux was it.

In my defence I have a Catu voltage tester next to me and I remembered the downloaded instructions came from France

 

[Robert Weaver]

I found this website helpful when comparing DVMs ...
https://www.eevblog.com/forum/testgear/multimeter-spreadsheet/

 

[mtt.tr]

I have a DiLOG DL9309 for when I want to do serious stuff and couple of cheap Chinese things that I tend to use most of the time. There are some stunning meters avaialble for under 20 quid but there's also some not so good. I've just bought a NENG620A - mainly because I was interested in what it was really like, no selector switch, just plug the leads in and it works out what you are doing and displays the result - I can plug it into the mains and read 240V then connect it across a resistor and not have to change settings or anything. Absolutley fantastic, measuring current I need to swap the red lead to a different socket but that's about it. All this for under 20 quid. Downside ? - won't measure anything under 0.5V or under 1mA.

As a general throw in the bag meter just in case you need it it's great but as a scientific instrument it could do better.

I've also recently acquired this :-
View attachment 291912
Which should have all the crusties on here shedding a tear

Next to it is the NENG 620A.

What you you rather have

I have the di-log MFT prior i had a. Kewtech really rather impressed with the dilog

 

[Ross365]

I found this website helpful when comparing DVMs ...
https://www.eevblog.com/forum/testgear/multimeter-spreadsheet/

There's another interesting site comparing budget DMM's , not so comprehensive, but possible more up to date?

 

[m_c]

I think people overthink multimeters.
I have a decent quality one (can't actually remember the make right now!) that is pretty accurate, and a couple cheap ones.

The cheap ones get the most use.
For automotive diagnostics, the vast majority of the time, you want to know if a sensor is getting power, or battery voltage is around where it should be. Even the cheapest multimeters are usually accurate to within a couple percent at lower voltages, and for diagnostics that is more than accurate enough. Even 5% off is still useable, as long as it's consistent, and you know what way it's off.

 

[premmington]

I think people overthink multimeters.
I have a decent quality one (can't actually remember the make right now!) that is pretty accurate, and a couple cheap ones.

The cheap ones get the most use.
For automotive diagnostics, the vast majority of the time, you want to know if a sensor is getting power, or battery voltage is around where it should be. Even the cheapest multimeters are usually accurate to within a couple percent at lower voltages, and for diagnostics that is more than accurate enough. Even 5% off is still useable, as long as it's consistent, and you know what way it's off.

I like these... (I got two of them)

Gotta be worth £20...

UNI-T UT118B LCD Digital Multimeters DC/AC Voltage Capacitance Resistance Tes●H | eBay

Capacitance (F): 3nF/30nF/300nF/3μF/30μF/300μF 3nF/30nF/300nF/3μF/30μF/300μF/3mF ±(3%+5). Input Impedance for DCV: ≥10MΩ. Resistance (Ω): 300Ω/3kΩ/30kΩ/300kΩ/3MΩ 300Ω/3kΩ/30KΩ/300kΩ/3MΩ/30MΩ ±(1%+3). LCD Backlight.

www.ebay.co.uk

 

[Robotstar5]

I like these... (I got two of them)

Gotta be worth £20...

UNI-T UT118B LCD Digital Multimeters DC/AC Voltage Capacitance Resistance Tes●H | eBay

Capacitance (F): 3nF/30nF/300nF/3μF/30μF/300μF 3nF/30nF/300nF/3μF/30μF/300μF/3mF ±(3%+5). Input Impedance for DCV: ≥10MΩ. Resistance (Ω): 300Ω/3kΩ/30kΩ/300kΩ/3MΩ 300Ω/3kΩ/30KΩ/300kΩ/3MΩ/30MΩ ±(1%+3). LCD Backlight.

www.ebay.co.uk

Handy looking tool, must resist

 

[mtt.tr]

its like voltage testers, to me cant beat the a martindale it has one function.

They kewtech has this stupid buzzed for 10 seconds to prove it works everytime you use it, then after 30 seconds you get another 10seconds of self test buzz

if working as a pair beeping wires out it was a bloody nightmare, or when proving dead you go neutral to earth you get a moments "oh **** its live, oh no its the self check"

 

[Wightsparks]

Having worked with a 2 ch Pico non-automotive scope for 18 months I just upgraded to the 4425A Automotive Pico. Their new Pico 7 software is a significant step up - esp on a touch screen and I got tired of needing another channel and having to faf around with time base and sample rate to get enough resolution. But then the scope is my go to diagnostic tool so the reasonably eye-watering price was justified for me, and all my home made tools still work with it. I'm with @premmington I use a scope a lot more on classics with no OBD than the modern stuff.

My best find in meters is my little UNI-T UT210E, which is a 2A (mA scale) -100A DC clamp meter. Very handy for auto diag. Not seen anything close for the money.

UNI-T UT210E Portable RMS AC/DC Digital Clamp Meter Capacitance Multimeter S6E5 738920337752 | eBay

Model: UT210E. Capacitance Range: 2nF/20nF~200μF/2mF~20mF. Capacitance Resolution: 1pF/10pF~100nF/1μF~10μF. Its resolution ratio is 1mA. Maximum range has maximum rage of 100A AC/DC; particular VFC start mode.

www.ebay.co.uk

Can use the above as a DVM but I got another UNI-T Meter, I wanted min/max, auto off, back light and reasonably chunky. Leads are dire though.

Pardon our interruption...

That UT81C for the OP looks like good bit of kit...(must resist I have 3 scopes already!)

 

[Robbie260]

I like these... (I got two of them)

Gotta be worth £20...

UNI-T UT118B LCD Digital Multimeters DC/AC Voltage Capacitance Resistance Tes●H | eBay

Capacitance (F): 3nF/30nF/300nF/3μF/30μF/300μF 3nF/30nF/300nF/3μF/30μF/300μF/3mF ±(3%+5). Input Impedance for DCV: ≥10MΩ. Resistance (Ω): 300Ω/3kΩ/30kΩ/300kΩ/3MΩ 300Ω/3kΩ/30KΩ/300kΩ/3MΩ/30MΩ ±(1%+3). LCD Backlight.

www.ebay.co.uk

You can get some really good pen multi meters that are as cheap as chips.

Out of interest what would your opinion be of only having 20Ms/s and 1Mhz bandwidth on a scope for automotive use, would it be enough? Just weighing up the TPI 440 and the Uni T UT81C and the uni t definitely out performs the tpi as a scope but in an industrial setting the TPI has more useful ranges available outside of the scope. The scope is mainly for Control circuits and automotive use buy just having a think about it and TPI dose make up for its losses in that it be of a much wider use too me overall.

 

[mtt.tr]

what about this https://www.tester.co.uk/siglent-sh...e-bandwidth-60-mhz-2-channel-5-7-inch-display

 

[Robbie260]

what about this https://www.tester.co.uk/siglent-sh...e-bandwidth-60-mhz-2-channel-5-7-inch-display

I do like that I'm must admit but I think that will be an eventually, it's a bit big for trotting round the globe in a small suitcase.

 

[sako243]

You can get some really good pen multi meters that are as cheap as chips.

Out of interest what would your opinion be of only having 20Ms/s and 1Mhz bandwidth on a scope for automotive use, would it be enough? Just weighing up the TPI 440 and the Uni T UT81C and the uni t definitely out performs the tpi as a scope but in an industrial setting the TPI has more useful ranges available outside of the scope. The scope is mainly for Control circuits and automotive use buy just having a think about it and TPI dose make up for its losses in that it be of a much wider use too me overall.

Keep in mind Nyquist's. A 1MHz bandwidth will only give you the ability to view 500kHz signals.

I haven't looked at the specs but I'd hazard that 20MSPS is the digital sample rate they want you to focus on (implying theoretical limit of 10MHz signals) but the 1MHz is the bandwidth of the analogue front end which means its all irrelevant (not entirely because of oversampling and dsp techniques you can play). But the 1MHz will effectively be a low pass filter before the ADC.

 

[Robbie260]

Keep in mind Nyquist's. A 1MHz bandwidth will only give you the ability to view 500kHz signals.

I haven't looked at the specs but I'd hazard that 20MSPS is the digital sample rate they want you to focus on (implying theoretical limit of 10MHz signals) but the 1MHz is the bandwidth of the analogue front end which means its all irrelevant (not entirely because of oversampling and dsp techniques you can play). But the 1MHz will effectively be a low pass filter before the ADC.

So let's just see if I have this right in my head.

Signal theoretically is limited by the sample rate.

But as there is a 1Mhz bandwidth your only going too get too view a signal 500khz each side of 0 on the sine wave.

Though if you muck about with attenuators etc you should be able too comfortably view a signal 5Mhz each side of 0 on the sine wave giving you a 10Mhz signal overall.