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Products => Test Equipment => Topic started by: GrayCat on November 05, 2020, 09:57:57 am

Title: RCL meters of type NJ100S / NJ200S / NJ300S
Post by: GrayCat 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 (http://myosuploads3.banggood.com/products/20201014/20201014230853NJ300USERSMANUALV1.3.pdf) 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?


Title: Re: RCL meters of type NJ100S / NJ200S / NJ300S
Post by: GrayCat on November 05, 2020, 10:02:09 am
(https://ae01.alicdn.com/kf/H48caeb061c394e9b8e7391ed2123329fz/NJ300S-LCR-Digital-Bridge-Handheld-Portable-Instrument-Impedance-Tester-Continuously-Adjustable-100-200-300kHz.jpg)
 

[attachimg=1]
Title: Re: RCL meters of type NJ100S / NJ200S / NJ300S
Post by: coromonadalix 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 ?
Title: Re: RCL meters of type NJ100S / NJ200S / NJ300S
Post by: GrayCat on November 05, 2020, 01:29:25 pm
Quote from: coromonadalix 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 ?

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?
Title: Re: RCL meters of type NJ100S / NJ200S / NJ300S
Post by: coromonadalix on November 05, 2020, 03:36:28 pm
https://www.banggood.com/50-300KHz-Handheld-Impedance-Tester-Bridge-LCR-Digital-Resistance-Measurement-Capacitance-Adjustable-Inductance-p-1738414.html?p=PA19205493643201607I&custlinkid=1304842&ID=6296786&cur_warehouse=CN (https://www.banggood.com/50-300KHz-Handheld-Impedance-Tester-Bridge-LCR-Digital-Resistance-Measurement-Capacitance-Adjustable-Inductance-p-1738414.html?p=PA19205493643201607I&custlinkid=1304842&ID=6296786&cur_warehouse=CN)


https://www.aliexpress.com/item/1005001501380888.html (https://www.aliexpress.com/item/1005001501380888.html)



well got me tempted  for the black friday ?? 
Title: Re: RCL meters of type NJ100S / NJ200S / NJ300S
Post by: GrayCat on November 05, 2020, 05:01:00 pm
Quote from: coromonadalix on November 05, 2020, 03:36:28 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.

Title: Re: RCL meters of type NJ100S / NJ200S / NJ300S
Post by: coromonadalix 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
Title: Re: RCL meters of type NJ100S / NJ200S / NJ300S
Post by: GrayCat 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 (https://youtu.be/POXDhURpUjY)
 
Measure of "precise" 1 nF and  10 nF capacitors:
Title: Re: RCL meters of type NJ100S / NJ200S / NJ300S
Post by: GrayCat on December 05, 2020, 10:27:02 pm
Measuring a 2 kOhm ±1% resistor:

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

Title: Re: RCL meters of type NJ100S / NJ200S / NJ300S
Post by: coromonadalix on December 06, 2020, 04:39:46 pm
can you open it to see the inside ?  thks
Title: Re: RCL meters of type NJ100S / NJ200S / NJ300S
Post by: GrayCat 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").


Title: Re: RCL meters of type NJ100S / NJ200S / NJ300S
Post by: GrayCat on December 07, 2020, 06:55:39 pm
All OpAmps were covered by some matte "epoxy".
Title: Re: RCL meters of type NJ100S / NJ200S / NJ300S
Post by: GrayCat 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 :-)
Title: Re: RCL meters of type NJ100S / NJ200S / NJ300S
Post by: GrayCat on December 07, 2020, 07:03:13 pm
Measiring of a 1 Ohm ±1% resistor.

Measiring of a 90.9 kOhm ±0.5% resistor.

Title: Re: RCL meters of type NJ100S / NJ200S / NJ300S
Post by: coromonadalix on January 11, 2021, 03:34:00 pm
Thank you very much for the teardown    :-+
Title: Re: RCL meters of type NJ100S / NJ200S / NJ300S
Post by: MegaVolt on November 26, 2021, 12:14:49 pm
There is more information about this device here:
https://ampnuts.com/lcr-nj100s/
https://ampnuts.com/start/
Title: Re: RCL meters of type NJ100S / NJ200S / NJ300S
Post by: Russ3000 on June 09, 2023, 09:53:07 pm
I bought the device on aliexpress. I will compare with 1832.
Title: Re: RCL meters of type NJ100S / NJ200S / NJ300S
Post by: ZhuraYuk on October 27, 2023, 07:31:11 pm
I just wonder how it shows 6 digits having only 12 bit ADC built in STM32