LCR-T4 electronics components tester ATMega328 - Test and Review

Transistor 13003 is seen once as NPN and after inversion as PNP?

Hello.
I'm just learning the basics of electronics and reading phrases like this:
(...) calibration, we do it by connecting pins 1-2-3 with minimal resistance (e.g. with two silver jumpers or redundant resistor ends). (...) with an experienced forum member, I'm starting to get confused.
(link)
What's with that resistance? To make it minimal, according to the author, you need to use silver jumpers (that is, in my opinion, relatively thin wires 0.5-1.5mm) or resistor tips (they are also very thin). According to the pattern R = (ro * l) /s the resistance is inversely proportional to the cross-section (ie thickness), i.e. the thinner the wire, the higher the resistance.
So should I use a thin or thick jumper, because I don't know anymore....
greetings

alek_troda wrote:

So should I use a thin or thick jumper, because I don't know anymore....

whatever. With such short lengths of conductor needed, it doesn't matter at all.

398216 Usunięty wrote:

whatever. With such short lengths of conductor needed, it doesn't matter at all.

I understand, but I will continue to dig in anyway: are the following statements true in this regard:
a) at small distances of the order of

alek_troda wrote:

and)

You can always count. You have the right data in the network - the specific resistance of copper, and even the resistance per meter of copper wire. You plug in the data and calculate. Easy?

alek_troda wrote:

b)

As above. Typical thickness of copper on a PCB is 35 microns (sometimes 70 microns for high current circuits) trace width - depends on necessity from say 1/10mm to 5mm or more (in case of mass).
It's nice that you are interested in such things, but it's a pity that you are not interested in looking for ready-made answers yourself. It's called "self-initiative" - I recommend it.

Thanks Deleted for this data!
greetings

I want to use a power supply instead of batteries, but what about calibrating the tester?
Is the calibration saved somehow in the device or is it maintained under current (by default from the battery)?
Because if each time you disconnect the LCR from the socket, the memory (calibration) will be erased, the point of such a modification is pointless.

Calibration is in the non-volatile EEPROM after the power is turned off

Dear friends, do you know where I can buy a display for the above-mentioned tester, I have been looking and looking and I will probably keep looking, the tape connecting the display with the printed circuit board was damaged, all because of the dedicated acrylic casing, which is too tight in the place of the tape.

dzg4 wrote:

Dear friends, do you know where I can buy a display for the above-mentioned tester, I have been looking and looking and I will probably keep looking, the tape connecting the display with the printed circuit board was damaged, all because of the dedicated acrylic casing, which is too tight in the place of the tape.

I don't believe it's all because of the dedicated acrylic casing, before assembling the next display I would look for an error, I had similar problems with the oscilloscope, it turned out that it was my fault when assembling it.

I already got one, it didn't display anything, I'm wondering if it was the main element of the system, or whether it was the action of an undischarged capacitor.

It is worth filling the empty space between the screen and the PCB with glue or silicone.
This will help you avoid problems with the screen falling out and the ribbon breaking.

Useful

Electronic components tester for ATmega - firmware update.
It is about update software in a very useful component tester based on the Atmega microcontroller.

Hi,

Transistors 9014 and 9015 have probably burned out in my tester, does anyone know what I can replace them with ?

BC547/BC557 just need to compare pinout.

Hello Folks ... My first entry (post) ... I read smarter when I have a problem.... I bought such an indicator or maybe rather an identifier at kitajca's and connected to the power supply ... lights up and ok ... but now I can't do calibration ... any 3 attempts to disconnect the battery have no effect to enter the options to be as it should be.... ... i.e. as described in the posts... calibration is not activated... just immediately the measurement of the component... the topic of T4 intrigued me enough (although (this topic is a side topic because I returned to electronics "{ out of boredom} after 3 heart attacks and 2 strokes I have a lot of time and focused on 3d printing and learning to master design programs .... ironworker by profession ... so I have a lump and you have to cut/obtain it to get something and in 3d it's like a different fairy tale "enchanted pencil" you draw and enter and there you have it... this topic brings together many outstanding people who have a lot of knowledge.... and a request to all, because no one thinks about it every day ... PEOPLE DO AN EVERY TIME (1x/ 2 years ~PLN 150) CELLULAR EXAMINATION, because we EAT anything and a stroke comes suddenly.... and it is a TRAGEDY... I was lucky to get lucky 2x.... but I want to keep reading you and learning.... i am 63 years old. but i want to master design and 3d printing and with simple methods i am trying to process plastic into filament but under ATMEGA control.... on a side note, is it possible to replace the n-coder with two up/down pins+ 3rd pin as enter?... to the moderator: the part of the test with health prevention content is not an advertisement but a concern to be able to benefit from the knowledge of other forum members in the future.... being in a stroke ward changes a person I repeat the question if it is possible to replace the n-coder with two up/down+ 3rd contact as enter

This tester should enter calibration mode as described. If it fails then it is either faulty or has unusual firmware.

As for the encoder, the easiest way to do this is to add a separate button as the aforementioned 'enter', this does not require modification of the firmware. Changing the encoder to two up/down buttons would rather require a firmware change.

Just out of curiosity what arteries do you check the flow in?

Thanks ... brightened me up a bit regarding T4 ... as for the test,,, painless .... usually ultrasound of the carotid arteries .... (left, right and 2 at the back ... about 15 min examination).... and what mental comfort that it is OK.... best regards and good health