Author Topic: RCL meters of type NJ100S / NJ200S / NJ300S  (Read 988 times)

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Offline GrayCat

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RCL meters of type NJ100S / NJ200S / NJ300S
« on: November 05, 2020, 09:57:57 am »
Hello!

Being in search for an RCL/impedance meter at around $100, I came across some NJ100S / NJ200S / NJ300S models. They have very good formal parameters, rich set of Variables to measure, but absolutely nothing is known about them! All I have found is some seller announsements, with the same pictures. And, User-Manual for NJ300S.

[attachimg=1]

NJ100S Specifications:
Code: [Select]
- Product model: NJ100S (fixed frequency)
- Power frequency: 50Hz. Frequency points: 15. Frequency point value: 50, 100, 600, 1000, 6000, 10000, 20000, 30000, 40000, 50000, 60000, 75000, 80000, 93750, 100000.
- Power frequency: 60Hz. Frequency points: 13. Frequency point value: 60, 120, 600, 1200, 6000, 12000, 24000, 30000, 38400, 48000, 60000, 75000, 96000.
- Measuring ranges:
* Resistance: 0.2mΩ~500MΩ
* Capacitance: 5fF~150mF
* Inductance: 0.5nH~100kH

These seem to be very good values, but no any confirmation for them.

Does anybody know anything about them?


Gray©at.
 
The following users thanked this post: coromonadalix

Offline GrayCat

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Re: RCL meters of type NJ100S / NJ200S / NJ300S
« Reply #1 on: November 05, 2020, 10:02:09 am »

 

[attachimg=1]
Gray©at.
 

Offline coromonadalix

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Re: RCL meters of type NJ100S / NJ200S / NJ300S
« Reply #2 on: November 05, 2020, 12:30:43 pm »
uh  aboslutely nothing    never saw them   ill try to find price for them,  where did you see them ?

Aliexpress ? Banggood ?
 

Offline GrayCat

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Re: RCL meters of type NJ100S / NJ200S / NJ300S
« Reply #3 on: November 05, 2020, 01:29:25 pm »
uh  aboslutely nothing    never saw them   ill try to find price for them,  where did you see them ?

Aliexpress ? Banggood ?

On EBay they are under the denoted names.

On Aliexpress, they are marked as "50Hz~100KHz-24 Frequency Points 2.4 Inch TFT Screen Handheld Tool LCR Meter Digital Bridge Impedance Tester", several sellers have them.

Any ideas?
Gray©at.
 


Offline GrayCat

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Re: RCL meters of type NJ100S / NJ200S / NJ300S
« Reply #5 on: November 05, 2020, 05:01:00 pm »
well got me tempted  for the black friday ??

No. I just want to know, is that NJ100S superior to Hantek 1833C. While there are plenty of info on Hantek, nobody can tell anything on the NJ.

Gray©at.
 

Offline coromonadalix

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Re: RCL meters of type NJ100S / NJ200S / NJ300S
« Reply #6 on: November 05, 2020, 06:02:31 pm »
Well someone has to buy one and do a teardown and firmware dump if its possible   .....

Until then  there's only speculations
 

Offline GrayCat

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Re: RCL meters of type NJ100S / NJ200S / NJ300S
« Reply #7 on: December 04, 2020, 11:18:00 pm »
Short video on testing a 80mm wire of 0.51mm diameter with NJ100S (in Russian):
 
https://youtu.be/POXDhURpUjY
 
Measure of "precise" 1 nF and  10 nF capacitors:
Gray©at.
 

Offline GrayCat

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Re: RCL meters of type NJ100S / NJ200S / NJ300S
« Reply #8 on: December 05, 2020, 10:27:02 pm »
Measuring a 2 kOhm ±1% resistor:

https://youtu.be/dpYJAKPU5j4 (in Russian)

Gray©at.
 

Offline coromonadalix

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Re: RCL meters of type NJ100S / NJ200S / NJ300S
« Reply #9 on: December 06, 2020, 04:39:46 pm »
can you open it to see the inside ?  thks
 

Offline GrayCat

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Re: RCL meters of type NJ100S / NJ200S / NJ300S
« Reply #10 on: December 07, 2020, 06:54:17 pm »
MCU: STM32F103RCT6 .
Charger TP4056 . Flash 25Q32JVS1Q .
OpAmps: U1 (voltage input), U9, U46, U47, U48 ==MCP6022. "Current Driver" U37==AD8532A. One more U7=AD8534A.
Switches something like 74LVC1G3157DCKR (markings "C5K" and "C5J").


Gray©at.
 

Offline GrayCat

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Re: RCL meters of type NJ100S / NJ200S / NJ300S
« Reply #11 on: December 07, 2020, 06:55:39 pm »
All OpAmps were covered by some matte "epoxy".
Gray©at.
 

Offline GrayCat

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Re: RCL meters of type NJ100S / NJ200S / NJ300S
« Reply #12 on: December 07, 2020, 07:01:04 pm »
The device was shipped without any probes. So, I had to make them myself.

The LCD is "YT240L030" on a ILI9341 controller, with 18-pin interface. So, you can buy a 3.2"-one, and feel more comfortable :-)
Gray©at.
 

Offline GrayCat

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Re: RCL meters of type NJ100S / NJ200S / NJ300S
« Reply #13 on: December 07, 2020, 07:03:13 pm »
Measiring of a 1 Ohm ±1% resistor.

Measiring of a 90.9 kOhm ±0.5% resistor.

Gray©at.
 

Offline coromonadalix

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Re: RCL meters of type NJ100S / NJ200S / NJ300S
« Reply #14 on: January 11, 2021, 03:34:00 pm »
Thank you very much for the teardown    :-+
 


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