This is an ESR (EPS) + meter of capacitors tank.
The device measures the EPS (equivalent sequential resistance) of the capacitor and its container measuring the charging time of the DC. The role of the current source performs the controlled stabilion TL431 and P-N-P transistor.
The capacity measures in the range of 1 - 150 000MKF, ESR - up to 10 ohms.
The whole design was successfully borrowed from the Pro-Radio website, where Oleg Gintz (he and GO and he was the author of the design) laid out his work for the overall review. This design was repeated not one dozen, or even one hundred times, tested and approved by the people. With proper assembly, it remains only to set correction coefficients for the capacity and resistance.
The device is assembled on a microcontroller PIC16F876A, a common LCD display of type WH-1602 based on HD44780 and scattering. The controller can be replaced by PIC16F873 - at the end of the article there are firmware on both models.
Capacity and ESR capacitors about 1000 μF measures for a split second. Also with great accuracy measures small resistance. That is, you can use when you need to make a shunt for an ammeter :)
The capacity of intrahemno is also well measured. Only, if there is inductance - can lie. In this case, we drop the element.
Case, Z-42, as a connector connections for a four-wire diagram, chose an old, kind, reliable USB 2.0 port.
Old, Soviet, felted electrolytic capacitor.
And this is a non-working capacitor from the processor power supply chain on the motherboard.
How does it work.
The capacitor is previously discharged, the current source is turned on, both inputs of the measuring amplifier are connected to CX, the delay of 3.6 μs is made to eliminate the influence of the stall in the wires. Simultaneously through the keys DD2.3 || DD2.4 Charges Condress C1, which actually remembers the greatest voltage that was on the CX. The next step is blocked by the keys DD2.3 || DD2.4 and turns off the current source. The inverting input of the BU remains connected to the CX, on which, after turning off the current, the voltage drops by the value of 10 mA * ESR. Here's actually all - then it is calmly measured the voltage at the outlet of the doors - there are two channels, one with ku \u003d 330 for limit 1 Ohm and ku \u003d 33 for 10 ohms.
On the forum source where the printed circuit board and firmware are posted - the seal was double-sided. On the one hand, all the tracks, on the other, the solid layer of the Earth and just holes under the components. I didn't have such a textolite at the time of the assembly, so I had to make land with wires. One way or another, it did not deliver special difficulties and did not affect the efficiency and accuracy of the device.
At the last picture - the current source, the source of the negative voltage and the power key.
The board is simple, the setting is even easier.
The first inclusion is to check the presence of + 5V after 78L05 and -5V (4.7V) at the output of the DA4 (ICL7660). The selection of R31 we achieve normal contrast on the indicator.
Turning on the device When the SET button is pressed, it puts it into the installation mode of the corrective coefficients. There are only three of them - for channels of 1 Ohm, 10 ohms and for tank. Changing the coefficients to the + and -, recording in EEPROM and the bust - the same set button.
There is also a debug mode - in this mode, the measured values \u200b\u200bwithout processing are displayed on the indicator - for the container - the status of the timer (about 15 samples per 1 μF) and both ESR measurement channel (1 step ADC \u003d 5V / 1024). Go to debug mode - when the "+" button is pressed
And one more point - setting zero. To do this, we climb the input, press and hold the "+" button and with the help of R4 we achieve minimal readings (but not zero!) At the same time on both channels. Not releasing the "+" button, press the SET - the indicator will display the conservation of U0 in EEPROM.
Next, measure the sample resistance of 1 ohms (or less), 10 ohms and the container (which trust), we determine the correction coefficients. The device is turned off, turn on when the SET button is pressed and set to-you, respectively, the measurement results.
Place in three stages, top view:
Device diagram:
I cite a small list of FAQ that has formed on the source.
Q. When connecting a resistor at 0.22 Ohm - writes - 1 with kopecks, when connecting a resistor in 2.7 ohms - writes ESR\u003e 12.044 ohms.
A. Deviations can be, but within 5-10%, and here 5 times. It is necessary to check the analog part, the perpetrators can be in descending order of probability:
current source
diff. amplifier
keys
Start from the current source. It must produce 10 (+/- 0.5) ma, it is possible to check it either in the oscilloscope dynamics, loading at 10 ohms - no more than 100 mV should be in the pulse. If you don't want to catch the needle - check in the statics - remove the jumper (zero resistance) between RC0 and R3, the lower end R3 to the ground, and turn on the milliammermeter between the VT1 collector and the Earth (it would be possible to interfere with VT2 - then when checking the collector VT1 is better to turn off from schemes).
In fact, the solution was: - "I confused the cutter 102 and 201 - and instead of 1 kiloma Zabubenil 200 ohms."
Q. Is it possible to replace TL082 on TL072?
A. To the OU of special requirements, there are no fields in the entrance, with TL072 should work.
Q. Why are two input connectors on your sector: one is connected to transistor diodes, and the other to DD2?
A. To compensate the voltage drop on the wires, the test element is better to connect the 4-wired circuit, therefore the connector is 4-pin, and the wires are combined together already on crocodiles.
Q. At idle, the negative voltage is 4 volts and strongly depends on the type of capacitor between 2 and 4 by ICL 7660 by the conventional electrolyte -2 in it.
A. After replacing the tantalum, dredged with 286 mother -4 V.
Q. The WH-1602 indicator does not work or the controller of the indicator is heated.
A. It is not true that the Winstar WH-1602 indicator is indicated in terms of power wiring, confused 1 and 2 conclusions! On ALLDATASHEET 1602L, which coincides with the basement, specified Winstar and in the diagram. I also caught 1602D - here it has "confused" 1 and 2 conclusions.
The inscription CX ---- is displayed in the following cases:
When measuring the capacity, time-out is triggered, i.e. For the allotted measurement time, the device did not wait for the switching of both comparators. This occurs when measuring resistors, short-circuited, or when the measured tank\u003e 150,000 μF, etc.
When the voltage measured at the DA2.2 output exceeds 0x300 (this is the indications of the ADC in the 16-richene code), the procedure for measuring the container is not performed and the CX is also displayed on the indicator.
With open applications (or R\u003e 10 Ohms) it should be.
The "\u003e" sign in the ESR string appears when the voltage at the output of DA2.2 0x300 (in the ADC units)
Summing up: Press the board, without errors, you solder items, we flash the controller - and the device works.
After a couple of years, I decided to make the device autonomous. According to the charger for smartphones, a STEP-UP converter was made to 7 at the output voltage. It would be possible to 5 B at once, but since the board is fixed in the housing on the glue - it did not wear a dying, and the voltage drop on the roll7805 in two volts - a small loss :)
My new designer looked like this:
The small handker of the converter was "shod" to the shoe shrink, it was cut off all wires, we will no longer need a connector for the crown. Just the hole in the case looks not very, so we will leave it, but the wires are bite. Inside the case there is no place for the battery, so I glued the battery on the back side of the device and attached his legs to him so that in working condition it was not lying on the battery.
On the front side cut holes for the power button and the LED indication of successful charging. Battery charge indication did not do.
Then he decided that such a boot was not bad to see the screen in the dark, in case of repair with candles, if the light turns off, and I want to work :)
But this after the more Ponte RLC-2 appeared. More information about this device in this article.
Recently, the way out of standing electrolytic capacitors has become one of the main causes of the breakdown of radio equipment. But for proper diagnostics, it is not always enough to have only a tank meter, so today we will talk about another parameter - ESR.
What is it, what does it affect and what is measured, I will try to tell in this review.
To begin, I will say that this review will differ fundamentally from the previous one, although both of these reviews about the measurement devices of the radio amateur.
1. This time is not a designer, but rather "semi-finished product"
2. To solder in this review, I will not.
3. Schemes in this review will not be, I think that by the end of the review it will be clear why.
4. This device is very narrow-plated, in contrast to the previous "multiple".
5. If a lot of people knew about the previous device, this almost nobody unknown.
6. The review will be small
For a start, as always, packaging. 
Claims did not arise, simple and compact. 
The equipment is completely Spartan, in the kit it is only the device itself and instructions, probes and batteries are not included. 
The instruction also does not shine informative, common phrases and pictures. 
Technical characteristics of the instrument specified in the instructions. 
Well, more understandable.
Resistance
Range - 0.01 - 20 ohms
Accuracy - 1% + 2 characters.
Equivalent sequential resistance (ESR)
Range - 0.01 - 20 ohms, operates in the range of capacitors from 0.1MKF
Accuracy - 2% + 2 characters
Capacity
Range - 0.1MKF - 1000MKF (3-1000 μF are measured at the frequency of 3 kHz, 0.1-3mkf - 72kHz)
Accuracy - depends on the measurement frequency, but is about 2% ± 10 characters
Inductance
Range - 0-60 μH at a frequency of 72kHz and 0-1200 μH at the frequency of 3 kHz.
Accuracy - 2% + 2 characters.
To begin with, I will tell you what it is - ESR.
Many quite often heard the word - capacitor, and some even seen them :)
If not seen, then the most common representatives are most common in the technique. 
In real life, the equivalent circuit of the capacitor looks as follows as shown in the figure below.
The picture shows -
C. - equivalent container, r. - leakage resistance, R. - equivalent consistent resistance, L. - Equivalent inductance.
And if simplified, then
Equivalent Capacity - This is a condenser in the "pure" form, i.e. without flaws.
Leakage resistance - This is the resistance that the capacitor discharges in addition to external chains. If you draw an analogy with a barrel of water, then this is a natural evaporation. It may be greater, it may be less, but it will always be.
Equivalent inductance - It can be said that this choke is included in a condenser consistently. For example, it is a capacitor folded rolled into a roll. This parameter interferes with a condenser when working at high frequencies and the higher the frequency, the greater the effect.
Equivalent sequential resistance, ESR - That is the parameter that we consider.
It can be represented as a resistor included consistently with an ideal condenser.
This is the resistance of conclusions, plates, physical limitations, etc.
In the cheapest capacitors, this resistance is usually higher, in more expensive Lowesr below, and there are still Ultra Lowesr.
And if it is simply (but very exaggerated), it is like gaining water in a barrel through a short and thick hose or through thin and long. The barrel will refill in any case, but the thinner the hose, the one will happen longer and with large losses in time. 
Because of this resistance, the capacitor cannot be instantly discharged or charged, in addition, when working at high frequencies, it is precisely this resistance that warms the capacitor.
But the worst thing is that the usual container does not measure it.
I often had cases when, when measuring a bad capacitor, the device showed a normal container (and even higher), but the device did not work. When measuring the ESR meter, it was immediately understood that the internal resistance of it is very high and it cannot work normally (at least where there was before it).
Some probably saw fumes condensers. If you cut off when the condensers are fluffy just lying on the shelf, the rest will be a consequence of increasing internal resistance. When working the capacitor, the internal resistance gradually increases, it occurs from the wrong mode of operation or from overheating.
The larger the internal resistance, the more the capacitor is beginning to warm up, the more heating from the inside, the more resistance grows. As a result, the electrolyte begins to "boil" and due to increasing internal pressure, the condenser swells.
But the capacitor does not always swell, sometimes in appearance it is absolutely normal, the container is in order, but normally does not work.
Connect it to the ESR meter, and it is already 1-2 ohm instead of the usual 20-30m.
I use the homemade ESR meter, collected many years ago according to the scheme from the PRORADIO forum, the structure of the design is GO.
This ESR meter comes across my review quite often and often ask me about him, but when I saw a ready-made device in new arrivals of the store, I decided to order it for the sample.
Still heated the interest of the fact that I did not find information about this instrument, well, it's more interesting :)
Externally, the device looks like "semi-finished", i.e. The collected design, but without the case.
True For convenience, the manufacturer established all this design to such plastic "legs", even plastic wrenches :) 
From the right end of the device there are terminals for connecting the measured item.
Unfortunately, the connection diagram is two-wire, which means that the longer the wires of the probes (if used) will be the greater the error of the testimony.
In more correct designs, a four-wire connection is used, one pair the condenser is charged / discharged, the voltage on the condenser is measured on another. In this version of the wire, you can do at least a meter long, there will be no global difference in the testimony.
Also near the terminals are two contacts of the printed circuit board, they are used when calibrating the device (I understood it later). 
The bottom is provided for the place to install the battery type 6F22 9 Volt (Crown). 
The device can also be powered by an external power source connected by the MicroUSB connector. When power connected to this connector, the battery is turned off automatically. With a frequent use, I would advise you to feed the device from the USB connector, as the batteries are stable rather significantly.
The photo also seen that the screed, with which the battery is attached, reusable. The screed lock has a tongue, when you click on which it can be opened. 
In the collected form, the design looks like this. 
The device is turned on and managed with only one button.
Inclusion - Pressing longer than 1 sec.
Pressing the operating mode switches the device between L and C-ESR measurements.
Turning off - Pressing the button for more than 2 seconds. 
When the device is turned on, first is displayed first the name and firmware version, then the inscription is warning that the capacitors must be defused before checking.
When you hold the button for more than two seconds, the inscription is displayed - power off and when the button is released, the device turns off. 
As I wrote above, the device has two working modes.
1. Measurement of inductance
2. Measurement of containers, resistance (or ESR).
In both mode, the instrument power supply voltage is displayed on the screen. 
Naturally let's see what is the filling of this device.
It is noticeable to look at the view of the previous tester of transistors, which indirectly speaks either about the ill-impaired scheme or about the best characteristics, it seems to me that in this case the second option is rather. 
Well, the display especially describes no sense, the classic 1602 option. The only thing was surprised - the black color of the textolite. 
I did the overall photo of the printed feet in two versions, with a flash and without, generally the device really did not want to be photographed by interfering with me all possible ways, because I apologize in advance for quality.
Just in case I remind you that all photos in my reviews are clicable. 
The "heart" of the device is a 12le5a08s2 microcontroller, I did not find information about this controller, but in the datashitis of its other version I slipped the information that it is assembled on the 8051 kernel. 
The measuring part contains quite a few elements, by the way, it is stated that the processor has 12 BIT of the ADC, which is used to measure. In general, such a bit is quite good, rather, it is interesting as far as real.
Initially, I thought to draw the scheme of all this "disgrace", but then I realized that it had no sense, since the characteristics of the device in terms of the measurement range are not very large. But if anyone is interested, you can try to turn over. 
Also, the operational amplifier is involved in the measuring scheme, as it is quite good, I used this in a signal amplifier with a current e-load shunt. 
Apparently this is the power switching node between the battery and the USB connector. 
On the bottom of the board almost nothing interesting, except the component button no: ( 
But I found an interesting even on an empty printed circuit board :)))
The fact is that when I got the device and played with him, it categorically could not force it to display the capacitance of the capacitor above the 680μF, it stubbornly showed OL and that's it.
After examining the fee, I could not not notice three pairs of contacts to connect the buttons (judging by the labeling).
At first I pinched Key2, to which I received on the screen - zero calibration (free translation) - approx.
Ha, I think, well, we are right.
But no, the calibration took me a lot of time, because because of the rarity device there is no information on it, in general. The only mention with the word calibration was. 
The closure of other contact pairs displays the constant values \u200b\u200b(apparently).
Moreover, there were still options, with other letters, and sometimes when closed Key3 slipped the inscription - OK (on English Esno) was saved. 
But back to calibration.
The device resisted all its own.
First, I tried to block the terminals with tweezers and calibrate so, but the device in the end showed the correct container and negative resistance in capacitors.
After that, I crotted two test patch on the board, the device began to show the correct resistance, but the range of measurement of the container was narrowed to 220-330 μF.
And after a long search in the internet, I came across the phrase (link is slightly higher) - Use 3cm Thick Copper Wire for Short Circuit to Clear
Translated this meant - use a copper wire with a thickness of 3 cm. I thought that the thickness in 3 cm is somehow cool and most likely meant 3cm lengths.
Sliced \u200b\u200ba piece of wire with a length of about 3 cm and the patch trottered on the board, it began to work much better, but still not so.
I took the wire more than two times and repeated the operation. After that, the device began to work quite normally and I spent further tests after this calibration.
For a start, I picked up different components, with which I will check how the device works.
In the photo, they are laid in accordance with the procedure for testing, only chokes lie on the contrary.
All components were checked from the smaller nominal to more. 
In front of the tests, I looked at the oscilloscope that gives the device to my measuring terminals.
Judging by the oscilloscope readings, the frequency is set to about 72 kHz. 
In terms of measurement of inductance, the testimony fully agreed with the components specified on the components.
1. Inductance 22MKHN
2. Inductance 150MKHN
By the way, in the process of calibration, I noticed that no manipulations were affected by the accuracy of the measurement of the container and inductance, but were reflected only on the accuracy of resistance measurement. 
With the inductance of 150mkgn the form of the signal on the terminals looked like this 
Capacitors of small capacity also did not arise.
1. 100nf 1%
2. 0.39025 μF 1% 
Signal form when measuring the condenser 0.39025 μF 
Further went electrolytes.
1. 4.7MKF 63V.
2. 10 MCF 450V.
3. 470MKF 100 volts
4. 470MKF 25 in Lowesr
Separately I will say about the condenser 10 MCF 450 volts. I was very surprised by the testimony and this is not a defect of a concrete element, as the condensers are new and I have two of them are identical. The testimony was also the same in both and other devices showed exactly the capacity of about 10 MCF. Moreover, even on this device, a couple of times slipped the testimony with a value of about 10 MCF. Why so, I do not understand. 
1. 680MKF 25 volts low impassion
2. 680MKF 25 Volt Lowesr.
3. 1000mkp 35 volts Normal Samwha.
4. 1000MKF 35 Volt SAMWHA RD Series. 
Signal form on contacts when testing the usual 1000mkp 35 volt SAMWHA.
In theory, when measuring the capacious electrolytes, the frequency should fall to 3 kHz, but it is clearly clearly seen on the oscillogram that the frequency has not changed in the process of all tests and was about 72kHz. 
1000mkp 35 Volt SAMWHA RD series sometimes issued such a result, it was manifested with a bad contact of the conclusions with measuring terminals. 
Already after I made a group photo, I measured and folded the details in its place, I remembered that I forgot to measure resistance to resistors.
To measure, I took a pair of resistors
1. 0.1 Ohm 1%
2. 0.47 Ohm 1%
The resistance of the second resistor is somewhat overestimated and clearly climbs 1% over the limit, rather even closer to 10%. But I think that it rather changes the fact that the measurement passes on alternating current and affects the inductance of the wire resistor, since the small resistor at 2.4 Ohma showed 2.38 Ohm resistance. 
When I was looking for information on the device, I stumbled on a photo of this device a couple of times, where the simultaneous measurement with different frequencies is shown, but my device does not displays it, again it is not clear why: (
Whether the other version, or something else, but there is a difference. I generally got the impression that it measures only at a frequency of 72kHz.
The high frequency of measurement is good, but it is always convenient to have an alternative. 
Summary
pros
In operation, the device showed quite a good accuracy (though after calibration)
If you do not take into account what I had to calibrate, then we can say that the design is ready to work "out of the box", but I admit that it was so "lucky."
Double nutrition.
Minuses
Full lack of information on the calibration of the device
Narrow dimension range
My device began to work normally only after calibration.
My opinion. To be honest, I have created a resistant dual impression of the device. On the one hand, I got quite good results, and on the other I received more questions than answers.
For example, I am 100% so 100% and did not understand how to calibrate correctly, I also did not understand why my condenser on 10 MCF is displayed as 2.3, well, it is not clear why the measurement takes place only at 72kHz.
I do not even know, recommend it or not. If you don't want to solder at all, you can use this or transistor tester from the past review, and if you want the best characteristics (mainly in the direction of the extension of the range) and it is not necessary to measure inductance, you can collect C-ESR meter from GO.
Very upset the upper range of measurement of the capacity of 1000mkf, although I calmly measured 2,200 μF, but the accuracy of the device fell, he began to clearly oversee the testimony of the tank.
In general, this is still all, I will very much better than any information on the instrument and gladly add it to the review. I admit that someone else is there, although it is very unlikely, since I did not find anything on him, although often all the devices are repetition of some known designs.
The goods are provided for writing a survey shop. The review is published in accordance with paragraph 18 of the site rules.
I plan to buy +45 Add to favourites I liked the review +48 +115Low ESR condenser meter
The device described here allows you to measure ultra-low resistance. Initially, it was designed to verify LOW ESR capacitors - with motherboards of computers, pulse power supplies, etc. However, its application is not limited to this. The probe perfectly measures the resistance of shunts, contacts, SMD jumpers, etc. With it, you can even learn the resistance of the short segment of the wire.
The instrument description page:
On the forum in the process of discussion of the article, the RL55 participant proposed a simpler and economic generator for this meter. This modification is used in this scheme. The device is fully universal: it can be easily converted to any measurement range, which is achieved by replacing the measuring bridge resistors.
Package: Esr.lay
Briefly about work: The generator on one transistor produces a sinusoidal signal with a frequency of about 100 kHz, which is supplied to the measuring bridge. In parallel, a test capacitor is connected to one of the bridge resistors. The measurement occurs at a high frequency, since the ESR capacitor itself is highly frequency. To measure simply ultra-low resistances, the high frequency would not be needed. The transistor can be used almost any, for example - KT315, CT3102 or their analogues in SMD execution.
Voltage on the contacts of the meter is less than the voltage opening any semiconductor, so you can check the capacitors without paying from the printed circuit board.
The voltage from the measuring bridge through the boost transformer enters the direction of the arrow, where the measured resistance can be determined by deflection of the arrow. A variable resistor 4.7k is needed to install "zero" with closed senses.
The first transformer is wound on a ferrite ring with a single-core wire in isolation. The primary winding of the second transformer can also be mounted by mounting wire, and the secondary - enameled, with a diameter of 0.2mm. Rings need to pick up magnetic permeability, here you need to experiment.
Note: The printed circuit board is calculated on the use of TMS transformers from CRT monitors and the first, author, the variant of the frequency generator. Without any alteration, it is suitable for an option with transformers on ferrite rings with a generator variant from RL55, while simply another location of parts on the same contact sites and tracks is used.
When assembling the meter must be configured. A resistor in the transistor base must be achieved by the maximum amplitude of pulses on the collector when shortened applications. In this case, the signal form must be as close as possible to the sinusoidal, and the frequency is close to 100kHz. This is necessary to preserve the voltage of the contour with the condenser 22nf. Therefore, as already mentioned, you need to experiment with various rings.
When using bridge resistors with 1 ohm resistance, the device "fits" about 0.1. With a decrease in the resistance of the bridge resistors, the device can be made even more sensitive. The scale of the indicator is non-linear and it must be placed on reference SMD resistances or SMD jumpers. In the output parts, even the length of the conductors can affect resistance.
Pinzeta contacts must be performed whether better, preferably from copper. When checking parts, the contacts of the tweezers are tightly compressed, the instrument arrow variace is set to zero. Then the contacts are also tightly applied to the measured part. To check the SMD components, a platform on one of the sides of the tweezers is also made.
PR302 diodes protect the ESR meter from damage if the measured capacitor is randomly charged. Diodes in the rectifier after an increase in transformer - Germany, for smaller voltage drop. All foil polygons, in addition to the meadow, the SMD components, are covered with a colorless rebar to protect copper from atmospheric corrosion.
There is more functional
Start
Yes, this topic has been repeatedly discussed, including here. I collected two options for the scheme Ludens. And they have proven themselves very well, nevertheless, all the previously offered options have shortcomings. The instrument scales with the arrow indicators are very nonlinear and require many low-level resistors for calibration, these scales must be draw and insert into the heads. The instrument heads are large and heavy, fragile, and the housings of small-sized plastic indicators are usually sealed and they often have a small scale. The weak destination of almost all previous designs is their low resolution. And for LOWESR capacitors, it is just necessary to measure the hundredths of Ohform in the range from zero to half Ohm. Also, devices based on microcontrollers with a digital scale were also proposed, but not everyone is engaged in microcontrollers and their firmware, the device is unreasonably complex and relatively expensive. Therefore, in the magazine "Radio" made a reasonable rational scheme - there is a digital tester from any radio amateur, and it costs a penny.
I made minimal changes. Corps - from a faulty "electronic choke" for halogen lamps. Food - Croon Battery 9 Volt and Stabilizer 78L05.. Removed the switch - Measure Lowesr in the range up to 200 ohms it is necessary very rarely (if you use, using a parallel connection). Changed some details. Chip 74hc132N., Transistors 2n7000 (TO92) and IRLML2502. (sot23). Due to the increase in voltage from 3 to 5 volts, the need for the selection of transistors has disappeared.
When testing, the device operated normally at a battery voltage of fresh 9.6 V to fully discharged 6 V.
In addition, for convenience, SMD resistors used. All SMD elements are perfectly soldered by a soldering iron Epsn-25. Instead of a serial connection R6R7, I used a parallel connection - it is so more convenient, on the board I provided a connection of an alternating resistor parallel to R6 to adjust zero, but it turned out that zero is stable in the entire range of stresses indicated by me.
Surprise caused the fact that the polarity of the VT1 connection was confused in the design "developed in the journal" - The stock and source is confused (correct if I'm wrong). I know that transistors will work and with such an inclusion, but for editors such errors are not allowed.
TOTAL
This device is working for about a month, its testimony when measuring capacitors with ESR per unit is coincided with the device according to the scheme Ludens. .He has already passed the test in combat conditions, when I have ceased to turn on the computer due to tanks in the power supply, while there were no obvious traces of "bravery", and the capacitors were not swollen.
Accuracy of the testimony in the range of 0.01 ... 0.1 ohms allowed to discharge dubious and not throw away the old desposable, but having normal capacitance and ESR capacitors. The device is easy to manufacture, details are available and cheeshev, the thickness of the tracks allows them to draw even a match.
In my opinion, the scheme is very successful and deserves repetition.
Files
Printed circuit board:▼ 🕗 25/09/11 ⚖️ 14,22 Kb ⇣ 669 Hello, reader! My name is Igor, I'm 45, I am a Siberian and an avid email. I invented, created and contain this wonderful site since 2006.
For more than 10 years, our magazine exists only to my funds.
Good! Halyava ended. You want files and useful articles - help me!
The fact that such a meter is needed by a radio amateur not only learned from others, but he himself felt when it took to repair an ancient amplifier - here it is necessary to reliably check each electrolyte standing on the board and find an endless or produce 100% replacement. Selected check. And I almost bought an advertised instructor called "ESR - Mikro" via the Internet. He stopped what was painfully well praised - "Through the edge." In general, he decided on independent actions. Since I didn't want to want, I chose the simplest, if not to say a primitive scheme, but with a very good (thorough) description. In the information and having some tendency to drawing began to breed its version of the printed circuit board. To fit into the housing from thick feltwaster. It did not work - not all the details were included in the planned volume. Dressed, drew the seal in the image and the likeness of the author's, stealing and collected. Collected it turned out. Everything came out very thoughtfully and neatly.
But the probion did not want to work, how much did not fight with him. And I did not want to retreat. For better perception, the scheme laid it on "his own". And so "native" (for two weeks of Najakmi), she became more understandable visually.
Scheme ESR meter
And the printed circuit board was tricky. She became a "double-sided" - from the second side, it was located the details that were not relevant on the first. For simplicity, the solution arising from the difficulty posted them "awn. There is not to the grace - the probe is needed.
Steel printed circuit board and sealed the details. This time I put it on the panel this time, to supply the power to the connector, which can be safely strengthened on the board using the soldering and the case in the future you can already "hang" on it. But the trigger resistor, with whom the probion earned best, found only such a thing - not miniature.
The reverse side is the fruit of pragmaticity and the peak of asceticism. You can only say something about probes here, despite the elementality of the performance, they are quite comfortable, and the functionality is so generally higher than the praise - are capable of contact with the electrolytic capacitor of any size.
Everything placed in an improvised body, the mounting place is the threaded connection of the power connector. On the housing, accordingly went minus power. That is, it is grounded. What neither is, and protection against filtering and interference. The trimmer did not enter, but always "at hand", it will now be a potentiometer. The fork from the radio broadcasting speaker, once and for all, will avoid confusion with multi-meter sockets. Nutrition from laboratory BP, but with the help of a personal wire with a fork from the Christmas garland.
And it, it is a miracle of non-zealous, took and earned, and immediately and as it should. And with the adjustment, no problems - corresponding to one wow, one millivolt is exhibited easily, about the middle position of the regulator.
And 10 ohms corresponds to 49 mV.
A good capacitor corresponds to about 0.1 ohms.
The faulty capacitor corresponds to more than 10 ohms. With the task, the probion coped with defective electrolytic capacitors on the board of the device being repaired. All details regarding this scheme will find in the archive. The maximum allowable ESR values \u200b\u200bfor new electrolytic capacitors are shown in the table:
And some time later, I wanted to give the console a more presentable look, however, the learned postulate "the best - the enemy of good" to touch him did not allow - I will do another, more elegant and perfect. Additional information, including the source device scheme, is available in the application. About your trouble and joy told Babay..
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