CAPACITORS
Condenser - one of the most widely used components of radio and consists of two metal plates - facings, separated by a dielectric. Facings are external pins through which the capacitor is connected to other elements. One of the important properties of the capacitor is that for the AC it is a resistance whose value decreases with increasing frequency.
The greater the charge can accumulate a capacitor at a certain voltage, the greater the electrical capacitance of the capacitor. Capacitance measured in Farad (F). This is a very large value, which in practice do not apply. In radio technology used capacitors from a few shares picofarads (pF) to hundreds of microfarads (mF).
Fig. 1. Capacitors
Abbreviated symbol (in accordance with GOST 11076-69 and OST 11.074.008-78 consists of the following elements:
FIRST ELEMENT-letter or letter combination defining the type of condenser: (K-constant capacity; CT-trimmer, manual-variable capacitance; COP-condenser assembly).
SECOND ELEMENT - the number designating the type of dielectric used. For fixed capacitors (10 - ceramic, for a rated voltage below 1600 V, 15 - ceramic, for a rated voltage 1600 V and above, 20 - Quartz, 21 - glass, 22 - glass, 23 - vitreous enamel; 26 - thin film with an inorganic dielectric ; 31 - Mica low-power, 32 - Mica high power, 40 -, paper and foil for rated voltage below 2 kV, 41 -, paper and foil for rated voltage of 2 kV and above, 42 - metallized paper, 50 - oxide (electrolytic) aluminum , 51 - oxide (electrolytic), tantalum, niobium, 52 - obemoporistye tantalum oxide, 53 - oxide-semiconductor; 58 - with a double electric layer (ionistory) 60 - Air, 61 - vacuum; 70 - polystyrene with foil facings, 71 -- polystyrene plates with metallized; 72 - PTFE, 73 - with metallized polyethylene terephthalate plates; 74 - Polyethylene with foil. For the variable capacitor and engineered (1 Vacuum 2-air; 3 with gaseous dielectric; 4 with a solid dielectric). For nonlinear capacitors (1-variconds 2-termokondensatory).
THIRD ELEMENT-serial number of developing a specific type, which can enter and lettering (R - for work in DC and AC currents, V - to work in ac circuits; Y to work in DC and pulse modes and - to work in pulsed mode). Full symbol consists of the abbreviated notation and values of key parameters and characteristics necessary for the order and record in the design documentation: (K75-10-250V-0, 1mkF ± 5% V-OZHO.484.865 TU).
In use as there are older types of capacitors in the classification is based on who took different signs: the constructive variety, technological characteristics, scope, performance, etc. (CD - disc capacitors; KM - ceramic monolith, SC - ceramic cast section; CSR capacitors mica pressed SUM - mica encapsulated compact; KBGI - capacitors, paper sealed insulated; MBGCH - metallobumazhnye sealed frequency; CEG-electrolytic capacitors sealed; IT - electrolytic tantalum volume-porous; PDA - ceramic trimmer capacitors).
Coded PARAMETERS
Fig. 2. Capacitors. Coded
For marking small capacitors use a coded symbol. Depending on how the chain can use a capacitor to him different requirements. The main parameters that characterize the capacitors, the following:
Nominal capacity - the capacity of the condenser, selected from a number of numerical values (Es, E6, E12 and E24). The capacitance of the capacitor case indicate the number and letter. The capacitance from 0 to 100 pF mark in picofarads, placing the letter "P" or "p" after the number, if it is whole, or in place of a point, if the number-fraction). Capacities from 100 pF to 0.1 microfarads stand in nanofaradah "H" or "n" and from 0,1 uF and above - in microfarads "M" (M or p) Table:
Tolerance in% | Marks. | Tolerance in% | Marks. | Tolerance in% | Marks. | Tolerance in% | Marks. |
---|---|---|---|---|---|---|---|
±0.001 | Е | ±0.05 | X | ±2.0 | G(Л) | -10 ..+30 | Q |
±0.002 | L | ±0.1 | В (Ж) | ±5.0 | J(M) | -10...+50 | T(Э) |
±0.005 | R | ±0.2 | С (У) | ±10 | К (С) | -10..+100 | Y(Ю) |
±0.01 | P | ±0.5 | D(Д) | ±20 | М(В) | -20 . .+50 | S(B) |
±0.02 | U | ±1.0 | F(P) | ±30 | N (Ф) | -20 ..+80 | Z(A) |
A tolerance - the maximum deviation (difference values) between the measured and rated capacity, when specified in NTD frequency and temperature.
Rated voltage and current - voltage and current at which the capacitor can be operated in the specified conditions during the period of service, keeping their options
Voltage. V | Marks. | Voltage. V | Marks. | Voltage. V | Marks. | Voltage. V | Marks. | Voltage. V | Marks. |
---|---|---|---|---|---|---|---|---|---|
1,0 | I | 6.3 | B | 40 | S | 100 | N | 350 | T |
2,5 | M | 10 | D | 50 | J | 125 | P | 400 | Y |
3.2 | A | 16 | E | 63 | K | 160 | Q | 450 | U |
4.0 | C | 20 | F | 80 | L | 315 | X | 500 | V |
Temperature coefficient of capacitance (TKE) - characterizes the relative change in capacitance from the nominal value when the temperature of the environment. Sign TKE can be negative (denoted by the letter "M"), positive (P), close to zero (MP). The letter "H" in the symbol group indicates that for these capacitors TKE is not standardized. Following the letter "N" numbers indicate the maximum allowable change in capacitance in the range of operating temperatures.
We mica capacitors Group TKE is denoted by the first letter on the body, the ceramic capacitors for each group corresponds to a certain body color or color label. The size of the first mark is twice the size of the second marker. If the color of the shell coincides with the color of the first marker, then the first mark does not pose. The temperature stability of capacitance (for segnetokeramicheskih capacitors with a nonlinear dependence of capacitance on temperature) characterize Relative changes in capacitance in the range of operating temperatures from -60 to +85 C.
Обозначение группы | Буквенный код | Цветовое обозначение | Номинальн. значение ТКЕ | ||
---|---|---|---|---|---|
Старое | Новое | ||||
Покрыт. корпуса | Маркировоч. точки | Маркировочной точки(штриха) | |||
П210 | синий | черный | без точки | +120 | |
П100 (П120) | А | синий | без точки | красный + фиолетовый | +100 |
П60 | G | серый | красный | без точки | +60 |
П33 | N | серый | без точки | без точки | +33 |
М110 | С | голубой | черный | черный | 0 |
М33 | Н | голубой | коричневый | коричневый | -33 |
М47 | М | голубой | голубой | голубой + красный | -47 |
М75 | L | голубой | красный | красный | -75 |
М150 | р | красный | оранжевый | оранжевый | -150 |
М220 | R | красный | желтый | желтый | -220 |
М330 | S | красный | зеленый | зеленый | -330 |
М470 | Т | красный | синий | голубой | -470 |
М750 (М700) | U | красный | без точки | фиолетовый | -750 (М700) |
М1500 (М1300) | V | зеленый | без точки | оранжевый + оранжевый | -1500 -1300 |
М2200 | К | зеленый | желтый | желтый + оранжевый | -2200 |
М3300 | Y | зеленый | зеленый | без точки | -3300 |
Обозначение группы | Буквенный код | Цветовая маркировка | Изменение емкости в % | ||
---|---|---|---|---|---|
Старое обозначение | Новое обозначение | ||||
Цвет покрытия корпуса | Маркировочная точка | Цветные точки или цветные штрихи | |||
Н10 | В | оранжевый | черный | оранжевый + черный | + 10 |
Н20 | Z | оранжевый | красный | оранжевый + красный | + 20 |
Н30 | D | оранжевый | зеленый | оранжевый + зеленый | + 30 |
Н50 | Х | оранжевый | синим | оранжевый + голубой | + 50 |
Н70 | Е | оранжевый | оранжевый | оранжевый + фиолет. | -70 |
Н90 | F | оранжевый | белый | оранжевый + белый | -90 |
Ceramic capacitors low (group I "by TKE) is used as a shunt, interlock, filter, and also for communication between the stages at low frequency. To save the resonant circuits at work in a wide range of temperatures necessary to use serial or parallel connection of capacitors, in which the TKE have different signs. What makes a temperature change frequency settings of the temperature-compensated circuit remains practically unchanged. Like all conductors, capacitors have some inductance. It is the greater, the larger the size of the capacitor plates and the internal connecting wires, the longer and thinner than its conclusions. In practice, for the work of bypass capacitors, in which the facings are made in the form of long strips of foil, folded together with the dielectric in a circular roll or any other form, in a wide range of frequencies, parallel to the paper (oxide) connect a ceramic or mica capacitor of small capacity.
Due to the fact that the dry oxide capacitors have a large manufacturing variation tolerances, they technically fulfilled the standard number of E6 Marking tantalum oxide-semiconductor capacitors (tear-shaped) is a color code:
Цвет маркировочного знака | Номинальная емкость | Четвертый элемент Ном Напр ,(Вольт) | ||
---|---|---|---|---|
Первый элемент (первая цифра) | Второй элемент (вторая цифра | Третий элемент (множитель) | ||
Серебряный | 10-2 | 2,5 | ||
Золотой | 10-1 | 1,5 | ||
Черный | 0 | 1 | 4,0 | |
Коричневый | 1 | 1 | 10 | 6,3 |
Красный | 2 | 2 | 102 | 10 |
Оранжевый | 3 | 3 | 103 | 16 |
Желтый | 4 | 4 | 104 | 40 |
Зеленый | 5 | 5 | 105 | 25 (20) |
Синий (голубой) | 6 | 6 | 106 | 32 (30) |
Фиолетовый | 7 | 7 | 107 | 50 |
Серый | 8 | 8 | 108 | |
Белый | 9 | 9 | 109 | 63 |
Nominal capacitance in picofarads is calculated as the product of two-digit number (as defined by the color of the first two lanes) by the factor (defined by the color of the third band). Capacitors with the value of tolerance ± 20% are marked with three colored stripes, from the side opposite to the capacitor.
желтый фиолетовый синий (4,7 мкФ) |
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синий серый синий серебряный (6,8 мкф 2,5В) |
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Distinctive color coding is used for marking of capacitors, rated operating voltage not exceeding 63V. Marking shall be in the form of colored dots or bands:
Цвет маркировочнои метки | Номинальная емкость в пФ | Допускаемое отклонение емкости | Номинальное напряжение в Вольтах | |
---|---|---|---|---|
Первая и вторая цифры | Множитель | |||
Черный | 10 | 1 | ±20 | 4 |
Коричневый | 12 | 10 | ±1 | 6,3 |
Красный | 15 | 102 | ±2 | 10 |
Оранжевый | 18 | 103 | ±0.25 | 16 |
Желтый | 22 | 104 | ±0.5 | 40 |
Зеленый | 27 | 105 | ±5 | 25 или 20 |
Голубой | 33 | 106 | ±1 | 32 или 30 |
Фиолетовый | 29 | 107 | -20...+50 | 50 |
Серый | 47 | 108 | -20...+80 | |
Белый | 56 | 109 | ±10 | 63 |
Золотистый | 82 | 10-1 | 1.5 | |
Серебряный | 68 | 10-2 | 2.5 |
Markings are applied in the form of colored rings or dots. Each color corresponds to a certain numerical value. The marks on the capacitors are shifted to one of the findings and are left to right. Bandwidth denotes the value of TKE is approximately two times more than others.
Цвет маркировочного знака | Номинальная емкость в пФ | Множитель | Допуск, % | ТКЕ | ||
---|---|---|---|---|---|---|
первая полоса | вторая полоса | третья полоса | четвертая полоса | пятая полоса | шестая полоса | |
Серебряный | 10-2 | ±10 | ||||
Золотой | 10-1 | ±5 | ||||
Черный | 0 | 0 | 1 | ±250 | ||
Коричневый | 1 | 1 | 1 | 10 | ±1 | ±100 |
Красный | 2 | 2 | 2 | 102 | ±2 | ±50 |
Оранжевый | 3 | 3 | 3 | 103 | ±15 | |
Желтый | 4 | 4 | 4 | 104 | ±25 | |
Зеленый | 5 | 5 | 5 | 105 | ±0.5 | ±20 |
Синий(голубой) | 6 | 6 | 6 | 106 | ±0.25 | ±10 |
Фиолетовый | 7 | 7 | 7 | 107 | ±0.1 | ±5 |
Серый | 8 | 8 | 8 | 108 | ±1 | |
Белый | 9 | 9 | 9 | 109 | ||
Нет цвета | ±20 |
Fig. 3. Capacitors. Marking color rings.
Capacitors with low value of admission (0.1% ... 10%) are marked with six color rings. The first three - the numerical value of the capacitance in picofarads, the fourth ring - a multiplier, the fifth ring - the tolerance, the sixth ring - TKE. Capacitors with the value of tolerance ± 20% are marked with four color rings. The first two - the numerical value of the capacitance in picofarads (as non-significant zero in the third digit is not marked). The third ring-factor, the fourth ring - TKE. The value of tolerance (fifth ring) is not marked.
Abroad, there is no standardized system of interstate symbol of capacitors and it is set by each company independently. Next consider only the basic, most frequently used codes foreign capacitors. Main basic scheme symbol of capacitors consists of ten elements:
FIRST ELEMENT - consists of alphanumeric (digital) symbols for the series (type) of the capacitor. For capacitors commercial and industrial performance - installed by the manufacturer, and for the special characters set standards MIL:
тип | номер стандарта | тип | номер стандарта |
---|---|---|---|
CCR | M1L-C-20 | CSR | MIL-C-39003 |
CHR | MIL-C-39022 | CWR | MIL-C-55365 |
CK | MIL-C-11015 | CX | MIL-C-49137 |
CRH | MIL-C-83421 |
SECOND ELEMENT - indicating the maximum voltage at which the capacitor can be used in defined circumstances. Operating voltage can point out a literal or a numeric code, as well as the specific value of this parameter is expressed in volts (V) or kilovolts (kV). Codes themselves are not standardized and are set by the manufacturer themselves:
номинальное напряжение, В | цифровой код фирмы Matsuo | буквен. код фирмы Multi Products | код чип-конденсаторов фирмы ITT | код фирмы Kemet (MIL-C-39003) | букв-цифров. код фирмы Rohm |
---|---|---|---|---|---|
3,15 | 3151 | ||||
4 | 4001 | G | |||
6,3 (6*) | 6301 | J | (В*) | ||
10 | 1002 | A | 010 (С) | ||
12 | 1202 | A | В | ||
16 (15*) | 1602 | В | С | (D*) | |
20 | 2002 | D | (E) | ||
25 | 2502 | С | E | 025 | |
35 | 3502 | V | 035 (F) | ||
50 | 5002 | D | Т | 050 (G) | R5 |
63 (75*) | 6302 | (H*) | |||
100 | 1003 | E | U) | 1 | |
200 | 2003 | 2 | |||
400 | 4003 | 4 | |||
500 | 5003 | F | |||
600 | 6003 | ||||
1кВ (1,5 кВ*) | 1004 | 1K0 (1K5*) | |||
2 кВ | 2004 | H2 | 2K0 | ||
3 кВ | 3004 | H3 | 3K0 | ||
5кВ | 5004 | H5 | 5K0 |
THIRD ELEMENT - indicates the nominal capacity of the condenser. In the symbol nominal capacity can be specified as a specific numerical value nominal value, expressed in pF, nF, uF. Rated capacity up to 999 pF - coded by the letter "p", up to 999 nF - coded by the letter "n", up to 999 microfarads - coded by the letter "m (u)". The letter is put in place the decimal point. However, the nominal capacitance of less than 10 pF is encoded by two digits and the letter "R"
емкость | код | емкость | код | емкость | код | емкость | код |
---|---|---|---|---|---|---|---|
0,1 пФ | р10 | 33,2 пФ | 33р2 | 10 нФ | 10п | 3,32 мкФ | 332 |
0,15 пФ | р15 | 59 пФ | 59р | 15 нФ | 15п | 5,9 мкФ | 59 |
0,332 пФ | р332 | 100 пФ | 100р | 33,2 нФ | 33п2 | 10 мкФ | 10 |
0,59 пФ | р59 | 150 пФ | 150р | 59 нФ | 59п | 15 мкФ | 15 |
1 пФ | 1р0 | 332 пФ | 332р | 100 нФ | 100 п | 33,2 мкФ | 332 |
1,5 пФ | 1р5 | 590 пФ | 590р | 150 нФ | 150п | 59 мкФ | 59 |
3,32 пФ | Зр32 | 1 нФ | 1п0 | 332 нФ | 332п | 100 мкФ | 100 |
5,9 пФ | 5р9 | 1,5 нФ | 1п5 | 590 нФ | 590п | 150 мкФ | 150 |
10 пФ | 10 р | 3,32 нФ | Зп32 | 1 мкФ | 1m0 | 332 мкФ | 332 |
15 пФ | 15р | 5,9 нФ | 5п9 | 1,5 мкФ | 15 | 590 мкФ | 590 |
As standard MIL-C-39008 rated capacity specified in the form of a specific value, expressed in picofarads in a package of three (four) digits. In the three-digit code - the first two digits meaningless, the third digit indicates the number of zeros following: 102 = 1 000 pF, 150 = 15 pF. In the four-digit code - the first three digits of meaningless, the fourth digit indicates the number of zeros following: 3322 = 33 200 pF = 33.2 nF.
The fourth element - indicates the tolerance capacity, which is usually indicated in the form of code:
код | допустимое отклонение емкости | код | допустимое отклонение емкости | код | допустимое отклонение емкости |
---|---|---|---|---|---|
В | +0,1 пф | F | ±1% | К | +10 % |
С | +0,25 пф | G | +2% | М | +20 % |
D | +0,5 пф | J | ±5% | Z | +80 ... -20 % |
FIFTH ELEMENT - indicates the temperature characteristics (TKE) for capacitors with a linear dependence of capacitance on the temperature or the relative change:
группа | сокращенное обозначение | цвет маркировочной точки | ТКЕ | диэлектрическая проницаемость | коэффициент диэл. потерь |
---|---|---|---|---|---|
Р100 | 0-А | красный / фиолетовый | +100 | 13 | - |
NPO | 2-A (N) | черный | 0 | 39 | - |
N030 | 0-J | коричневый | -30 | 41 | 04 |
N075 | 1-J | красный | -75 | 43 | - |
N150 | 2-J (P) | оранжевый | -150 | 45 | 1,5 |
N220 | 3-J (Q) | желтый | -220 | 45 | - |
N330 | 4-J (R) | зеленый | -330 | 48 | 0,5 |
N470 | 5-J (S) | голубой | -470 | 51 | - |
N750 | 6-J (T) | фиолетовый | -750 | 85 | 2 |
N1500 | 7-J (V) | оранжевый /оранжевый | -1500 | 130 | - |
N2200 | 3-A (W) | желтый / оранжевый | -2200 | 260 | 3 |
N3300 | 5-A (X) | зеленый / оранжевый | -3300 | 370 | 3,5 |
N4700 | 6-A | голубой / оранжевый | -4700 | 400 | 4 |
N5600 | 9-J | черный / оранжевый | -5600 | 470 | 5 |
Capacitors with a nonlinear dependence of the capacitance on temperature classified into 15 groups and have the following encoding:
Условное обозн.группы | буквенный код | интервал температур,°С | допускаемое изменение емкости, % |
---|---|---|---|
Y5F | ±7,5 | ||
Y5P | ±10 | ||
Y5S | -30 ... +85 | ±22 | |
Y5U | А | +22 ... -56 | |
Y5V | +22 ... -82 | ||
X5F | ±7,5 | ||
Х5Р | -55 ...+ 85 | ±10 | |
X5S | ±22 | ||
X5U | +22 ... -56 | ||
X5V | . -55 | +22 ...-82 | |
Z5F | В | ±10 | |
Z5T | С | ±22 | |
Z5S | -10 ... +85 | +22 ...-56 | |
Z5U | Е | +22 ...-56 | |
Z5V | F | +22 ...-82 |
In the symbol of ceramic capacitors, manufactured according to the standard MIL-C-3914, indicates the current-temperature characteristics of the code of two letters. The first letter of the code means the temperature range (A =- 55 ... +85 C, B =- 55 ... +125 C, C = -55 ... +155 ° C). The second character means a change in capacitance in the range:
изменение емкости по сравнению с ее значением при +25 °С | вторая буква кода - вольт-температурная характеристика | |
---|---|---|
без напряжения на конденсаторе | при напряжении на конденсаторе | |
(+30...-30) 106 1/°С | (+30...-30) 106 1/°С | G |
(+60...-60) 106 1/°С | (+60...-60) 106 1/°С | Н |
+15...-15% | +15...-40% | Р |
+22...-56% | +22...-66% | W |
+15...-15% | +15...-25% | Х |
+30...-70% | +30...-80% | Y |
+20...-20% | +20...-30% | Z |
Sixth, seventh, eighth and tenth element - consists of alphanumeric characters denoting the size of hull, structure and coverage of the findings, as well as the type of packaging.
NINTH ELEMENT - is a literal character, which was the reliability of capacitors. Standard MIL-C-39008, the following levels of reliability: M = 1%, P = 0,1%; R = 0,01%; S = 0,001% of failures.
LABELING OF FOREIGN CAPACITOR color-coded.
Fig. 4. Capacitors. Marking color dots.
The exact composition of the marking elements set firms depending on dimensions of capacitors. For the color-coded markings, consisting of four bars (or dots), the nominal capacity (in picofarads) is expressed in three bands - this is the numerical value of the capacity and the factor 10n (where n-any integer from 2 to 9). Is followed by the band, indicating Capacitance tolerance in percentage. All the bands are shifted to one of the findings, counting from left to right:
Цветмаркировочного знака | Номинальная емкость | Четвертый элемент (допуск в %) | ||
---|---|---|---|---|
Первый элемент (первая цифра) | Второй элемент (вторая цифра) | Третии элемент (множитель) | ||
Серебряный | 10-2 | ±10 | ||
Золотой | 10-1 | ±5 | ||
Черный | 0 | 1 | ||
Коричневый | 1 | 1 | 10 | ±1 |
Красный | 2 | 2 | 102 | ±2 |
Оранжевый | 3 | 3 | 103 | |
Желтый | 4 | 4 | 104 | |
Зеленый | 5 | 5 | 105 | ±0,5 |
Синий (голубой) | 6 | 6 | 106 | +0,25 |
Фиолетовый | 7 | 7 | 107 | ±0,1 |
Серый | 8 | 8 | 108 | +0,05 |
Белый | 9 | 9 | 109 |
Plate film capacitors are marked text symbols (digits - the nominal value, and the letters - a factor, the permitted deviation and operating voltage) or colored stripes, the value of which is given below:
Номинальное значение емкости | |||
---|---|---|---|
Величина емк.мкф | Первый пояс (головка конденсатора) | Второй пояс (кольцо) | Третий пояс (кольцо) |
0.01 | коричневое | черное | оранжевое |
0.015 | коричневое | зеленое | оранжевое |
0.02 | красное | красное | оранжевое |
0.03 | оранжевое | оранжевое | оранжевое |
0.04 | желтое | фиолетовое | оранжевое |
0.06 | гинее | серое | оранжевое |
0.10 | коричневое | черное | желтое |
0.15 | коричневое | зеленое | желтое |
0.22 | красное | красное | желтое |
0.33 | оранжевое | оранжевое | желтое |
0.47 | желтое | фиолетовое | желтое |
0.68 | синее | серое | желтое |
1.0 | коричневое | черное | зеленое |
1.5 | коричневое | зеленое | зеленое |
2.2 | красное | красное | зеленое |
3.3 | оранжевое | оранжевое | зеленое |
4.7 | желтое | фиолетовое | зеленое |
6.8 | синее | серое | зеленое |
FOURTH BELT (allowable declined, from the nominal): ± 10% white, black * 20%
FIFTH BELT (nominal voltage): red = 250, yellow = 400 V
Countdown zones (rings) begins on the side opposite the capacitor.
Marking dry tantalum oxide capacitors (tear-shaped) is a color code shown in the table below.
Counting the rings starts from the top of the conclusions point location at the same time indicates the polarity of the capacitors:
цвет маркировки | номинальная емкость. мкФ | Номинальное напряжение, В (цвет основания) | ||
---|---|---|---|---|
первый элемент (головка) | второй элемент (кольцо) | третий элемент множит.(точка) | ||
Черный | 0 | 1 | 10 | |
Коричневый | 1 | 1 | 10 | |
Красный | 2 | 2 | 100 | |
Оранжевый | 3 | 3 | ||
Желтый | 4 | 4 | 6,3 | |
Зеленый | 5 | 5 | 16 | |
Синий | 6 | 6 | 20 | |
Фиолетовый | 7 | 7 | ||
Серый | 8 | 8 | 0.01 | 25 |
Белый | 9 | 9 | 0,1 | 3 |
Розовый | 35 |
It is also possible and other options for labeling tantalum capacitors
First Source: radvs.boom.ru/rdv2.html. Ed. 02.06 VF Gainutdinov