Cheap component tester/Oscilloscope

[rogs]

The adaptor I've been using with my DMM to test transistors is shot....The contacts are very 'iffy', and you have to present the component in the correct orientation.
It's always been a pain to use...now it's worse!

Looking for something to replace it, I came across this: https://www.aliexpress.com/item/1005005202074391.html
At the time it was less than £40 ($50) including tax and shipping ... so I thought it was worth a pop...
And I've been pleasantly surprised. Component testing via a DIL ZIF socket -- and inserted in any orientation ... much easier!
Plus -- a simple battery operated 'scope and a signal generator -- and a simple volt meter.
The 'scope worked better than I expected - only 500KHz bandwidth though.

Nicely presented - rechargeable lithium battery.
MCX connectors not my first choice for 'scope leads - you really need a MCX to BNC adpaptor, but htose are not expensive.
Useful little device to chuck in the toolbox -- and it's a really nice change to use non-oriented ZIF connections for component testing!

Can't really go wrong at that price....

 

[jasonallenh]

The adaptor I've been using with my DMM to test transistors is shot....The contacts are very 'iffy', and you have to present the component in the correct orientation.
It's always been a pain to use...now it's worse!

Looking for something to replace it, I came across this: https://www.aliexpress.com/item/1005005202074391.html
At the time it was less than £40 ($50) including tax and shipping ... so I thought it was worth a pop...
And I've been pleasantly surprised. Component testing via a DIL ZIF socket -- and inserted in any orientation ... much easier!
Plus -- a simple battery operated 'scope and a signal generator -- and a simple volt meter.
The 'scope worked better than I expected - only 500KHz bandwidth though.

Good value for money I've found?...

I can't remember who shared this, but for transistors, this seems to be an excellent option-

https://www.peakelec.co.uk/acatalog/dca75-dca-pro-semiconductor-analyser.html
There's a less feature dense version called the dca55 that can be had for under $100 as well. I've seen the Fnirsi scope is probably fine, but those have been scrutinized closely and seem to have issues. As a brand, you get what you pay for with them.

 

[PermO]

Fnirsi, I have one of those... I thought it would be an upgrade from my old component tester.

Well, it is not, it can't tell a transistor from a diode, reads capacitors wrong on small values, my old little 9V battery thingy is much better.

The scope function, meh... also connected the tonegen to a tuner and A is now 452Hz apparently...

It's beyond mediocre.

And you can... yes you can...

 

[Whoops]

This component tester is greap,
the model is MK 328

 

[rock soderstrom]

This component tester is greap,
the model is MK 328

View attachment 126189

I've had one of these for years and I'm satisfied.

I've just bought a second one. Special offer on Aliexpress for 6€ something incl. shipping.

I'll use this on the move. I'm curious to see if it's as good, it now has a color display.

https://a.aliexpress.com/_Eulxb45

 

[chilidawg]

I've had one of these for years and I'm satisfied.

I've just bought a second one. Special offer on Aliexpress for 6€ something incl. shipping.

I'll use this on the move. I'm curious to see if it's as good, it now has a color display.

https://a.aliexpress.com/_Eulxb45

View attachment 126191

Some of my tech friends are using that on a daily basis and they seem happy with it. It cost $40 here because Aliexpress no longer ship to my country.

The only downside with the tool is when you need to measure low value capacitors (picofarads), you have to parallel it with a higher value capacitor to bring up the capacitance otherwise the measurement will be wrong.

 

[rock soderstrom]

Just arrived, in record time! 7 days!

The device does what it is supposed to, the test probes are of dubious quality. No problem, I'll replace them.

I measured small capacitances down to 50pF quite well, below that it becomes increasingly inaccurate. But my Uni-T UT890D+ can't do that either.

I'm satisfied...

 

[ruffrecords]

I just ordered one. Handy to have by your side to check component values when assembling PCBs.

Cheers

Ian

 

[13engrsapper]

I can say the Peak stuff we have works fine - It is not as accurate as the big tektronix transistor curve tracer, but it gets the job done last and easy.

 

[13engrsapper]

I am not sure if it is still the same, but the peak we have for transistors, with a USB cable and computer, does curve traces

 

[OneRoomStudio]

I've used one of these for years, and it works perfectly
https://www.aliexpress.us/item/2251832780578455.html

 

[Script]

Just arrived, in record time! 7 days!

The device does what it is supposed to,

Cheap on Ali and does it's job on diodes, LEDs, transistors, inductors, caps. Had one for long. Very handy, fast and easy-to-use. Probes are crap indeed though. Mine is different colour, but same same.

 

[Quantum J Audio]

I find my TC1 very useful. Worth taking a minute to calibrate it

 

[GJB17]

I have the (later) TC-3 version... very useful. I have a few "spare" pieces of this device if anybody wants to purchase. Can match on-line pricing.

 

[MicMaven]

SIDEBAR -- I purchased this LC tester on eBay really CHEAP. . . It seems to work OK, but I am no expert.

Question: Can I measure capacitors and inductors in place, or must I lift one lead or remove the component from the circuit for testing. The meager instructions are no help and I do not trust just any advice found floating about the ethereal Internet.​

Thanks loads. James

 

[Script]

Don't know that unit.

Anyway, components can't really be tested like this in circuit. Figure a cap is in parallel with another cap. What measurement do you get? -- At least have to lift one leg. But better to take out of circuit entirely. Some caps sit too close to the PCB or might get damaged when bent too far. Lifting one leg of a resistor or a diode usually works though. Still, be careful with your diodes...

 

[Brian Roth]

SIDEBAR -- I purchased this LC tester on eBay really CHEAP. . . It seems to work OK, but I am no expert.

Question: Can I measure capacitors and inductors in place, or must I lift one lead or remove the component from the circuit for testing. The meager instructions are no help and I do not trust just any advice found floating about the ethereal Internet.​

Thanks loads. James

View attachment 133952

Out of curiosity, what are the measurement ranges for L and C?

Bri

 

[abbey road d enfer]

I use this very same unit with satisfaction.
The only issue is the limited voltage range for zeners, and the fact that when it does not recognize the component, it gives an erroneous result instead of question marks.

 

[MicMaven]

Out of curiosity, what are the measurement ranges for L and C?

THE PRODUCT DESCRIPTION SAYS:
- Modle:LC200A.
- Supply power: +5v ,miniUSB interface ,4pcs AA battery (NOT included).
- Measurement accuracy:1%.
- Capacitance measuring range: 0.01 pF - 10uF.
- The minimum resolution: 0.01 pF.
- Big Capacitance measuring range1uF-100mF/minimum resolution:0.01UF.
- Inductance measuring range: 0.001 uH - 100mH.
- Big inductance measuring range: 0.001 mH - 100H.
- The minimum resolution: 0.001uH.
- Test frequency range: L/C about 500KHZ/Big inductance 500HZ.
- Effective display digits: 4 digits.
- LCD display mode: 1602.
- Size:15cm x 9cm x 3.5cm - 5.91inch x 3.54inch x 1.38inch.

James

 

[MicMaven]

Anyway, components can't really be tested like this in circuit.

Point well taken. The type of thing I measure looks like this (attached) a simple bias tee DC voltage injector to power a remote transmatch (automatic impedance matching network) in the back yard. This one tried to melt down. You can see where the epoxy fumes stuck to the metal case. (see photos)

I want to measure its three - yes, THREE - internal components to build a backup unit. The manufacturer wants ... are you sitting down? ... a whopping $100 US for another one! Really. Just three components, three common panel connectors, and a small metal project box - crazy, eh? Of course I will make one from scratch before I spend that much brass on such a simple thing - shoot, that would surely cut too deeply into my bourbon budget!

So, um, at least in this case, do ya think I need to pull these components to get good measurements? Or is it simple enough I can measure them in place? (A serious question as I am still a rookie!)

Thanks for the touch. James