Best CHEAP LCR meter for small capacitors and inductors?

[ranchero]

I periodically need to measure small capacitors (under 20pF, sometimes under 5pf) and small inductors (under 150NH).
I currently have DE-5000 which has 100kHz range and should theoretically measure these small L and C just fine. But readings on these small L and C are very unstable even though I'm using TL-21 adapter with very short leads (like 4cm).
Since it's more like a hobby I can't justify purchasing real good LCR meter (like PM6304).
Do you guys think any less expensive LCR meter (let's say, under $200) will do any better than DE-5000? I would be totally happy with 10%-15% tolerance on these small L and C.
Funny fact - every review on Youtube shows tests of electrolytic capacitors and big inductors, which almost any rectangular box with gauge on it able to measure, but never - very small values.   

Question#2 - what would be best setup to measure small SMD L and C (like 0402, 0603)? Currently I'm using small board with 2 pins, just soldering SMD elements to the board for measuring.

[tautech]

What's cheap ? 
Splash out on a pair of decent smart tweezers and never look back.
See here:
https://www.eevblog.com/forum/projects/smart-tweezers/

[2N3055]

under $200 ?

No, you cannot get better LCR than DE-5000 for that money.

But your problem is not the meter. Such small capacities are measured by using mechanically stable measurement adapters and 4wire setup. Tl-21 is not stable enough for this. Such adapters can be very expensive to buy...

Other option to measure small L/C is a VNA. You would also need a measurement fixture for that...

Also what Tautech said, some tweezers (quality ones, that cost 200-300€) are much better at measuring small L/C because there are no cables and is more mechanically compact setup.

Measuring such small values is all about dealing with parasitics in measurement setup.

[ranchero]

Smart Tweezers only have 10kHz frequency max, specs say that they will measure inductance from 0.5uH which is useless for me.

What if I will create fixture which will fit directly into DE-5000 slots, with little board on top, and solder SMD part directly to that board? Virtually - no wires.
Will it make measurements any more stable? Actually, stable readings even more important for me than actual values (but actual values would be nice of course).

[coromonadalix]

your "cheapest"   will be the avr component tester project here  loll

[egonotto]

Hello,

is an indirect measurement via the resonant frequency with L or C connected in parallel an alternative?

Best regards
egonotto

[ranchero]

I'm trying to keep as simple as possible and avoid indirect measurement.
Basically - I have board with damaged/missing SMD L or C and no documentation available whatsoever. And I have good board, I can temporary borrow corresponding L or C from it to measure values.

The other problem I'm running into - when buying small inductors on Aliexpress sellers very often (in fact - almost always) just send random values, like 500NH instead of 100NH, 220NH instead of 130NH and so on.
Inconsistent readings don't help to solve this puzzle at all.

[skander36]

A cheap alternative LC meter that claim to measure up to 500 KHz is MLC500.
But for SMD you still need a good fixture.

https://www.amazon.com/Digital-Precision-Automatic-Inductance-Capacitance/dp/B083SG8TYV
On Aliexpress even more cheap - 50 $

[2N3055]

Smart Tweezers only have 10kHz frequency max, specs say that they will measure inductance from 0.5uH which is useless for me.

What if I will create fixture which will fit directly into DE-5000 slots, with little board on top, and solder SMD part directly to that board? Virtually - no wires.
Will it make measurements any more stable? Actually, stable readings even more important for me than actual values (but actual values would be nice of course).

Tweezers I have go to 100kHz.

Actually that fixture is exactly what I wanted to say. Make a fixture that will be mechanically stable and will sit on top of meter. Than calibrate with fixture in place and you will get way better results.

[ranchero]

A cheap alternative LC meter that claim to measure up to 500 KHz is MLC500.
But for SMD you still need a good fixture.

https://www.amazon.com/Digital-Precision-Automatic-Inductance-Capacitance/dp/B083SG8TYV
On Aliexpress even more cheap - 50 $

Hmm...Anyone tried it in person? Looks like "too good to be true". Need to do some research on this.

Update - found review on this - not very promising. Impossible to believe that $60 tester can do what $300 testers can't.

[ranchero]

Tweezers I have go to 100kHz.

Model?

[kripton2035]

may be you can build this yourself, at least for measuring small caps ?
https://www.romanblack.com/onesec/CapMeter.htm

[mcovington]

NH?  Nanohenries?  That is a TINY inductance.  Do you mean millihenries or microhenries?

[2N3055]

Tweezers I have go to 100kHz.

Model?

LCR Research LCR Pro1 Plus Smart LCR Tweezers

[ledtester]

A cheap alternative LC meter that claim to measure up to 500 KHz is MLC500.
But for SMD you still need a good fixture.

https://www.amazon.com/Digital-Precision-Automatic-Inductance-Capacitance/dp/B083SG8TYV
On Aliexpress even more cheap - 50 $

Does anyone know how this meter works?

From the odd test frequencies I am guessing it is a clone of the AADE LC IIB meter:

https://sites.google.com/site/vk3bhr/home/lcm1

You can find several forum threads here on it, including this one:

https://www.eevblog.com/forum/rf-microwave/suitable-alternative-to-the-aade-lc-meter/

[mawyatt]

What may work with your DE-5000, and give you a more stable and repeatable results is a SMD fixture for use with a proper lab type LCR meter like shown. You can get name brand fixtures for ~$200 (Tonghui) or no name ones like shown for ~$100.

To connect this to the DE-5000 you'll need to prepare a BNC cable adapter that uses a TL-21 modified with 4 BNC cables to attach to the SMD fixture. We were going to do this but never got around to it since we now have 2 lab grade LCR meters.

Should fit within your $200 budget.

If you need these types of measurements often, then seriously consider a lab grade LCR meter with necessary fixtures. For example the Tonghui TH2830 (only goes to 100KHz tho) supports measurements in the pF and nH range with good results. We have some some in-house references SMD caps like Venkel COG 4.7pF and 10pF that show repeatability better than 0.01pF with this instrument & fixture (a Hioki IN3536 shows similar results over a broader frequency range).

Edit: Also consider the TL-22 Tweezers for the DE-5000.

Best,

[2N3055]

I still think that measuring in low nH / pF range would be best done with cheap VNA and proper fixture...

[nctnico]

I periodically need to measure small capacitors (under 20pF, sometimes under 5pf) and small inductors (under 150NH).
I currently have DE-5000 which has 100kHz range and should theoretically measure these small L and C just fine. But readings on these small L and C are very unstable even though I'm using TL-21 adapter with very short leads (like 4cm).
Since it's more like a hobby I can't justify purchasing real good LCR meter (like PM6304).
Do you guys think any less expensive LCR meter (let's say, under $200) will do any better than DE-5000? I would be totally happy with 10%-15% tolerance on these small L and C.

Question#2 - what would be best setup to measure small SMD L and C (like 0402, 0603)? Currently I'm using small board with 2 pins, just soldering SMD elements to the board for measuring.

There is this XJW01 LCR bridge that is pretty cheap and does proper 4 wire measurements. In my experience it will measure small capacitors just fine. I have not tried inductors. Ideally you'd use an SMD test fixture but that alone will set you back around $200. But a board will also work as a test fixture. In such a setup I'd solder SMA connectors to the board and use short SMA to BNC cables to connect to the XJW01. I don't know what kind of board you are using now but if you have not done that already, you could design one yourself. A double sided board with traces that keep the measurement to be a 4-wire measurement as much as possible would be good and only costs a few dollars to order from JLCPCB, Seeed, etc.

[fourfathom]

NH?  Nanohenries?  That is a TINY inductance.

Yes it is, and we deal with nH inductors all the time in RF work, especially as the frequency gets above 10 MHz or so.

[mawyatt]

I still think that measuring in low nH / pF range would be best done with cheap VNA and proper fixture...

Depends on the frequency range of interest, a VNA is certainly the correct choice for higher frequencies.

For example, if you consider the impedance of 2pF at 100KHz, that's ~796K ohm, a 50 ohm reference VNA will have a difficult time accurately resolving this high an impedance, whereas a quality LCR should work well. However, if we change to say 10MHz, then the impedance drops to ~7.96K, within the range of the VNA and pushing the frequency limits of the LCR. In between these overlapping frequency ranges it becomes a toss up which instrument is the better suited.

Why most of us have a VNA and LCR meter

Best,

[mawyatt]

I periodically need to measure small capacitors (under 20pF, sometimes under 5pf) and small inductors (under 150NH).
I currently have DE-5000 which has 100kHz range and should theoretically measure these small L and C just fine. But readings on these small L and C are very unstable even though I'm using TL-21 adapter with very short leads (like 4cm).
Since it's more like a hobby I can't justify purchasing real good LCR meter (like PM6304).
Do you guys think any less expensive LCR meter (let's say, under $200) will do any better than DE-5000? I would be totally happy with 10%-15% tolerance on these small L and C.

Question#2 - what would be best setup to measure small SMD L and C (like 0402, 0603)? Currently I'm using small board with 2 pins, just soldering SMD elements to the board for measuring.

There is this XJW01 LCR bridge that is pretty cheap and does proper 4 wire measurements. In my experience it will measure small capacitors just fine. I have not tried inductors. Ideally you'd use an SMD test fixture but that alone will set you back around $200. But a board will also work as a test fixture. In such a setup I'd solder SMA connectors to the board and use short SMA to BNC cables to connect to the XJW01. I don't know what kind of board you are using now but if you have not done that already, you could design one yourself. A double sided board with traces that keep the measurement to be a 4-wire measurement as much as possible would be good and only costs a few dollars to order from JLCPCB, Seeed, etc.

Those XJW01 LCR bridge look interesting, but only show a max frequency of 7.8KHz. Looks like some old-school design with many discrete thru-hole components, but should be fun to play with. Believe the DE-5000 also uses a bridge concept but with a custom chip pair. We've compared the DE-5000 with our two lab grade LCR meters over a wide range of Cs, Rs and a few Ls, the results were indeed impressive for a handheld low-cost instrument!!

Best,

[nctnico]

I did some tests with my XJW01 but it's usefull range is from -say- 10pf or from 1uH. So not a fit for the requirements for the OP.

[Vojtech]

Consider ET432, it has Kelvin clips, I am very satisfied with it.

[mawyatt]

Just did a quick check with the DE-5000 measuring a 53mm length of solid #12 Cu wire, this should be ~41.7nH per calculations and we measured 43nH (100KHz) with TL-21 fixture. For ACR we get 0.002 ohms tho, and this is calculated as 281u ohms, with DMM6500 we get 271.7u ohms, so obviously below the DE-5000 resolution.

Also measured a 17.5 turn open wire inductor at 292nH (100KHz) with DE-5000 & TL-21, TH2830 with 292.737nH and IM3536 with 292.17nH.

BTW the core DE-5000 is a 4 wire Kelvin Type System, the TL-21 Fixture brings the each 2 Force/Sense wire sets to the Bottom of each Alligator Clip as shown below with the 2 wire inductors. This is a left over from a TL-21 we modified some time ago for a true Kelvin setup with long Kelvin leads and clips.

Anyway, just some measurement and hope this helps.

Best,

[ranchero]

Just to clarify - I do have TL-22 tweezers, from my experience it doesn't do any better on small L and C comparing to TL-21. I do have Kelvin clip and I've seen video of modification to use them with DE-5000, just didn't have a chance to try it myself.
So far - reading this thread - I think, as few people suggested - I need to make small fixture without wires and try to use it directly on DE-5000.
 
Other question - is it normal to do calibration on DE-5000 every time you turn it on? It seems that values do change a bit after calibration.

LCR Research LCR Pro1 Plus Smart LCR Tweezers

Specs are very promising. $300 - a bit more expensive than I would like them to be...But I will think about them, thank you.

Consider ET432, it has Kelvin clips, I am very satisfied with it.

Have you tried it with very small SMD L and C? Would you share your setup and results?