Variable capacitor high voltage. High voltage variable capacitor design.

Variable capacitor high voltage My original plan was to make it a fixed capacitor out of a length of coax for a single 40m frequency. [1] [6] Capacitor Technology Capacitance Range Peak Repetitive Voltage Continuous RMS Current Frequency; Snubber Capacitors: 0. 1. Passive PASSIVE PLUS OFFERS: CUSTOM CAPACITOR ASSEMBLIES. -Leaded or leadless: Leaded Surface Mount AC Power Ceramic Capacitors AC Safety Capacitors (UL/TUV Certified) Automotive Grade Mid-Voltage, High Capacitance AM Series EMI X2Y Filters & Decoupling Capacitors High Temperature Surface Mount MLCCs The maximum working voltage depends on the physical dimensions of the capacitor. Stators are made from glass epoxy copper clad PCB material. Mouser is an authorized distributor for many trimmer & variable capacitor manufacturers including Knowles, Vishay & many more. $9. Somehow, over the years, DL5DBM's website got lost in the mists of the internet, leaving only my Although it has a low dielectric constant, it can be used in a variety of simple ways to make very good high voltage capacitors. The capacitance is variable from 18-136 pF. HAM radio. The following are general specifications pertaining to Jennings vacuum capacitors. The voltage is applied to the fixed-free beam. Air variable capacitors use air as the dielectric and feature a lightweight construction and high voltage handling capabilities. Sort by: Showing 1-30 of 30 item(s) Active filters. TDK's UHV and FHV series high-voltage ceramic capacitors feature low dissipation and excellent voltage-capacitance characteristics using patented strontium titanate (SrTiO3) for dielectric material. Mouser offers inventory, pricing, & datasheets for Trimmer/Variable Capacitors. Previous slide Next slide. Connectors Internal breakdown voltage is primarily determined by the spacing of the opposing plates and a high vacuum level. The second downside to air variable capacitors is the ratio of max to minimum capacitance they can provide is somewhat restricted. 00 1pc: $213 2-4pcs $178 5pcs+ $155 Min Capacitance pF: 22pF Max Capacitance pF: 1017pF Max Voltage, Vrms: 1100 V Max Current, Arms: 2 Arms ATM-9 $ 61. Air variable capacitors have low loss, high Q, can handle high voltages depending on the spacing between the plates, and can offer a very wide tuning range from a single capacitor (covering 3-4 bands on a single loop is achievable). By using a vacuum variable you can greatly reduce the size of the capacitor. Sure, you can buy these capacitors, but they are often expensive and hard to find exactly what you want. Mechanical vs. Insulation between rotor and stator is achieved through 1/4" thick, high quality, military spec ceramics riveted to the plated steel end A variable capacitor is a capacitor whose capacitance may be intentionally and repeatedly changed mechanically or electronically. Two stators and one rotor are used for the primary capacitor. The fixed-free beam is one plate of the capacitor. A high operating voltage requires that the distance between plates is sufficient to avoid electrical breakdown of air. They are commonly used in voltage-controlled oscillators, parametric amplifiers, and frequency multipliers. ) Your plate spacing looks similar to the cap in my MFJ loop, which has been fine at 100W, but they make a big point of how their plates are polished smooth etc. Click here to request a sample; Variable Capacitors; Silicon Capacitors; High Temperature Film Capacitor; I built an efficient loop antenna for ham radio (see earlier project). o/a 1. 2. 00 1pc: $61 2-4pcs $40 5pcs+ $24 Air Gap: 0. 7666 $ 7. However, those types of variable capacitors taken from radios generally perform well for listening, but when transmitting from the transceiver, they can withstand a power of 1 to 8 watts depending on their Variable Tuning & Load Capacitors ; The M-73 is a high-voltage, heavy-wattage, continuous duty capacitor. Variable Capacitor Types. Due to the use of paraelectric ceramics, they realize stable voltage characteristics, thereby achieving high reliability. Sub-mini Piston Trimmer Cap 1. Johanson’s HPJJ202G124J3QA001C offers a capacitance of 0. Adjustable 1. A. P. Variable. High-quality Russian high-voltage vacuum variable capacitor KP1-8 5-250pF 5kV Cart. Why aren't there many (voltage controlled) variable capacitors above ~1000pF? 2. 922n51 $ 1. READY TO SHIP - ONLY 29 LEFT IN STOCK! Building a high voltage air variable capacitor. KP1-8 4-100pF 5kV. for impedance matching Description: Standing 4. 200°C Rated Radial, High-Power/Voltage Capacitors in Energy & Drilling. 7pF Max Cap: 8. Specifications Fixed vs. Current ratings are for normal convection cooling in ambient temperature of 25 °C unless otherwise specified. 340 In Stock: 1: $61. I wanted to build my own variable capacitor with about 15 or 20 pF range for the loop that tolerates a 100 W transmitter. The highest capacitance ratings can be found in what many people call A variable capacitor can change its capacitance in response to an applied voltage. Instead I started looking at a Trimmer / Variable Capacitors are available at Mouser Electronics. Insulation between rotor and stator is achieved through 1/4" thick, high quality, military spec ceramics riveted to the plated steel end plates. When like a variable resistor. This allows for a higher voltage rating than an air dielectric [1] using a smaller total volume. 1; 2; Next. These capacitors provide capacitance tuning ranges from 2 pF to 100 pF, although the high-voltage rating component is relatively large, measuring about 5 inches long (Figure 2). Diodes Variable Capacitance (Varicaps, Varactors) are in stock at DigiKey. Voltage across the capacitor advances from zero (fully discharged) to the supply voltage The realm of Variable Capacitor High Voltage on AliExpress introduces a plethora of options, designed to cater to various technical requirements and applications. Fixed capacitors simply have a fixed, nonadjustable capacitance value. This low loss butterfly loop tuning capacitor has a voltage rating of 4200 Volts rms. Phase-locked loops are used for the frequency synthesizers that tune many A vacuum variable capacitor. The latest revision of the M90 incorporates AC Rated Voltage (WVAC): 10000 volts VARIABLE CAPACITOR BASICS A variable capacitor is a capacitor whose capacitance may be intentionally and repeatedly changed mechanically or electronically. This is our MFJ-23, a larger low loss butterfly loop tuning capacitor. done Quickly one finds that a high value, high voltage butterfly capacitor becomes LARGE. Since the controlling voltage can be applied automatically, manual tuning is no longer required. Butterfly variable capacitors have two stators and a rotor arranged in such a way that turning the rotor will vary the capacitance between the Variable capacitors have capacitance values that can be vari What is a variable capacitor (VAC)? VACs are passive components with capacitance values that can be varied according to the control voltage. The depletion layer appears in the p-n junction when a diode is reverse-biased. High-Q / Low ESR Capacitors – C/P Series: High Q (>10,000) – EIA N Series: Ultra Low ESR – X Series: Low ESR Bypass; Custom Capacitor Assemblies; Broadband Capacitors; Single Layer Capacitors – Standard Edge Trimmer/Variable Capacitors are available at Mouser Electronics. The word varactor is formed by the words: variable reactance or resistor variable. 016– 032 Variable capacitors Vacuum and gas-filled relays 033– 038 Vacuum and gas-filled relays overview 039– 044 Vacuum relays — SPST Jennings vacuum capacitors Features • High voltage rating – The dielectric strength of the vacuum permits optimized voltage rating for a given size and capacity, in addition to freedom High-Voltage DIY Butterfly Capacitor For Magnetic Loop Antennas TA1LSX (TA2WK) Butterfly Capacitor. Mar 21, 2024. 500V or less. Trimmer Capacitors – Air Tubular Trimmers – Sapphire Trimmers – Zirconia Trimmers PPI ANNOUNCES NEW VARIABLE CAPACITOR LINES. Variable capacitor 15-110 pF / 5,5 kV. If Finding high voltage capacitors can be tricky. These are designed for high capacitance and high voltage. g. By JMC mfg. Datasheet. Each cap includes our own contactor wheel and arm design. Guglielmo Marconi, a pioneer of radio, used rudimentary variable capacitors. , 6 amps nom. 5 volts nom. The maximum operating current for variable vacuum capacitors is limited by temperature rise and working voltage. Oct 16, 2024. See my newer Introduction: High Voltage Butterfly Capacitor for Loop Antennas - TA2WK (TA1LSX) These magloops also have a very narrow bandwidth, requiring a variable capacitor for tuning to the operating frequency. The bellows contains the vacuum, allowing Designed for medium-power applications High voltage and High frequency tolerance Variable capacitors can be classified into air dielectric variable capacitors and solid dielectric variable capacitors based on the dielectric materials used. The capacitance characteristics and the rate of change of capacitance (as a function of voltage) are important for a variable Variable capacitors like air capacitors and trimmer capacitors are adjustable manually. This includes hight voltage capacitors, which are crucial in ensuring stability and safety in electrical circuits subjected to extremely high voltage. electronic tuning. 8 to 36 kV. Order: 1 piece. 2 - 10pF, New. It should be avoided to apply a high voltage to the electrode of variable capacitor when it is pulled-in, hence a new structure configuration should be considered: instead of using a Other variable capacitor types exist, such as variable glass capacitors for high-temperature applications with a high Q; trimmer capacitors with plastic dielectrics with much lower RMS voltage, current ratings and Q values; adjustable mica capacitors, though these have small capacitance values with a limited adjustment range; and voltage variable capacitors or CVDB-320-6N538 Jennings 10-320pF 5kV Variable Vacuum Capacitor Used Excellent Condition * No longer available for export MFR: Jennings SKU: CVDB3206N538-P Voltage: 1200vdc Canister Dimensions: 3. Go. 2015), area (Barzegar et al. practical for variable capacitors. Shipping per piece: $9. The rotor-stator type of capacitor comprises two metallic plate sets. Table credit: Wikipedia. Single gang 6-39pf with screw driver adjust shaft. These capacitors mainly find uses in radio Variable vacuum capacitors incorporate movable plate electrodes. varicap diodes are commonly used in high frequency Typically, variable capacitors can be broadly classified by gap (Afrang et al. In contrast, the capacitance of a varactor diode is controlled by a reverse bias voltage. Key Features. It provides a resistance, reactance or variable capacitance, which is why it is called a varactor diode. Connectors - Unidapt . Under some high voltage conditions you can't use anything else. I'm working on my own design inspired by the coke can variable capacitor. 4kv. Theoretical analysis. They are used in equipment such as high-powered broadcast transmitters, amateur radio RF amplifiers and large antenna tuners. In the partial specification for a VVC shown in Fig. 5 mm. 49: 10: $49. 77651181 Hammarlund Variable Capacitor, 60-420pf 10kv, 49 plates, Spacing: 0. Assembly has Gear driven motor drive mounted on aluminun plate and comes with DC Motor from Globe Industries (Part # C-25A-511). Capacitor applications. BST device are based on Barium Strontium Titanate and vary the capacitance by applying high voltage to the device. Thread starter Andy1845c; Start date Jan 11, 2009; Status Not open for further replies. Once the capacitor is charged through a voltage source, then one plate of the capacitor will be charged positively whereas the second plate will negatively be charged. How does a variable capacitor work? High-value capacitors have lower TC than low-value capacitors. As voltages on the order of thousands of volts develop across the capacitor, air variables or vacuum variable capacitors are used. PPI's Commercial High Voltage Capacitor line provides high quality components for your higher voltage circuits. Material: Ceramic. A reverse biased diode acts like a (small) capacitor. , 1/100 hp at 15000 rpm min. Air capacitors collect dust with their open construction. A piston trim capacitor is a type of variable capacitor, specifically designed for fine-tuning or "trimming" the capacitance value, often used in radio frequency (RF) circuits for applications like setting oscillator frequencies or optimizing circuit performance. 12/01/2025. The current capacitors are 4-30nf range! Usually those Capacitors are very rare and expensive but many high Variable capacitors have capacitance values that can be varied by applying voltage to their electrodes. General Electric - 21L6013 - Capacitor, oil-filled. Our air variable capacitors have a range of 1. 4 cm. Variable capacitors can be adjusted by the user, using either mechanical or electronic means. Why do we use polarized capacitors? 5. x 10. Trimmer/Variable Capacitors 0. POLARON. Next Last. The TSF, H, and GA series are applicable to Gas Insulated Switchgear. Home / Alphabetical Category Listing / High Voltage Capacitors / Air Variable Capacitors Air Variable Capacitors. 34 Wide x 3. They have a dedicated analogue control input and therefore introduce less non-linearities than High voltage variable capacitor design. 5-8 pF +/-100 500V HIGH VOLTAGE A1M8HV; Passive Plus now offers a comprehensive range of High-Q Variable capacitors including Air Tubular, Sapphire, PTFE, and Air Plate trimmers. Capacitors can feature either fixed or variable capacitance. While this capacitor does work, it will not handle 100 W. 39. 01 to 10 µF: 500 to 10,000 V: 10 to 120 Arms The principle is a series array of ferroelectric capacitors with bias voltage applied in parallel through high-value resistors that are incorporated in the IC-like structure. to tune a radio (therefore they are sometimes called tuning capacitors), or as a variable reactance, e. High-Power Radial Capacitors play a crucial role in energy and drilling industries, particularly for signal conditioning circuits in drilling equipment. 9pF Max Voltage: 500Vrms 73-1-32-99N $ 281. Its thickness increases in reverse proportion to the reverse voltage. 26. They are used in various devices such as switches in distribution networks, circuit breakers in substations, and medical and industrial x-ray imaging devices. We have proposed a new RF MEMS variable capacitor to achieve high linearity, wide tunability and low actuation voltage. Upon customer request, certified test reports will be made available. . 00 1pc: $281 2-4pcs $234 5pcs+ $205 Min Capacitance Homebrew high voltage variable capacitors. For the first time, an on-chip MEMS component has been used in the substrate integrated Capacitors high voltage; Capacitors low voltage; Variable capacitor (air) Variable capacitor (air) There are 30 products. 016 inches Min Cap: 1. +1 631-425-0938 Contact Search C. Used * No longer available for export High Voltage. 05" High; New Old Stock, No longer available for export Add to Cart. About 3 mm copper was removed on three sides to prevent arcing. Class 2 high-power capacitors: high voltage laser power supplies, power circuit breakers, induction furnaces, etc. While most all diodes exhibit a junction capacitance that decreases as the amount of Any idea what voltage it will handle? (I didn't see that in your article, sorry if I missed it. Each stator is 15. Capacitors for applications involving applied DC voltage should be tested on a DC dielectric strength Open Frame PCB has (5) Sprague Type 12 High Voltage Silver Mica Capacitors, Non-Polarized, Axial Leads, JOHANSON DIELECTRIC - JMC9301 Capacitor, variable. Once the At that time, the voltage across the capacitor would be equal to the supply voltage of the battery. Variable capacitors are distinguished by the fact that their capacitance can be changed. * You may not request samples of the same part Variable High-voltage Capacitor: after my microwave capacitor died iv'e been looking for a good replacement, id heard of the overhead slide and tin foil ones but i figured i may as well laminate tin foil if i'm going to make that, after Breakdown voltage for FR-4 laminate is ~20kV/mm. The capacitance varies depending on the applied reverse bias voltage. 562in x 9. These are also known as tuning capacitors due to their common Variable capacitor Mechanically controlled. The following describes building and testing. 66 µF and a voltage rating of 2000 VDC. Because of their non-polarity and wide range of capacitances, voltage ratings, and sizes, ceramic capacitors can also be utilized as general-purpose capacitors. Please view our large selection of trimmer and variable split-stator variable air capacitor Conventionally-constructed RF air capacitors are not immediately my favourite type of capacitor. 1 of 2 Go to page. Variable capacitors are often used in L/C circuits to set the resonance frequency, e. High voltage rating Voltage controlled capacitors (varicaps or varactors) are diodes. High vacuum is 20-40kV/mm for comparison. [2] Voltage-controlled oscillators have many applications such as frequency modulation for FM transmitters and phase-locked loops. Skip to Main Content +49 (0)89 520 462 110 . Dielectric strength is tested using a low current, high potential source at 60 Hz voltage. A variable capacitor is one of the widely used components in radio frequency (RF) circuits. High voltage variable capacitor design. 5" high by 4. KP1-4 5-100pF 25kV. The latest revision of the M90 AC Rated Voltage (WVAC): 10000 volts; Applications: RF / Microwave Capacitors Here we report the design and fabrication of a new type MEMS based, digital variable capacitor with a high-k dielectric material. 180,00 $ KP1-4 5-100pF 25kV Russian High-Voltage Vacuum Variable Capacitor. 95. In mechanically controlled variable capacitors, the distance between the plates, or the amount of plate surface area which overlaps, can be changed. I played with cutting the coax to the right length and finally decided against this method. 260pF/12kV Variable Butterfly Capacitor for a Loop Antenna kits VA6POP. At high frequencies ,air-dielectric capacitors are most apt to be used; however, in low-frequency applications, ceramic trimmers perform better. The main purpose of the isolation amplifier here is to prevent high voltage or current from passing from one section to another, protecting the circuit from danger and preventing A variable-capacitance diode is a type of diode that uses the capacitance characteristics of the depletion layer. In this paper, we present and analyze a novel tunable capacitor TDK's ultra high voltage ceramic capacitors have over 40 years of development and sales history. 75 x 4. One of the design goals for MEMS varactors has been to realize linear 73-1-100-54 OEP Variable Capacitor 35-280pf 4. C6 are about 200pF each at 0V bias. 25 Used. Also known as a Trimmer Capacitor, these are designed for fine adjustments or calibration in RF Circuits providing the ability to vary capacitance, allowing precise tuning and optimization of electronic circuits in LC filters, radio The voltage rating of a variable capacitor is the maximum voltage that can be reliably withstood, usually defined as the dielectric breakdown voltage. From the datasheet you can see the relationship between the bias voltage (P13 to P14) on the capacitance (P11 to P12): In this case, C1. Showing all 10 results. 2 cm. 5-8 pF +/-100 500V HIGH VOLTAGE. The applications of the variable capacitor include the following. Description: Standing 4. Rotor-Stator Capacitor. Industrially they are used in plasma generating equipment, for dielectric heating, and in semiconductor manufacturing. We will find these units mainly in high-voltage power supplies. These end plates are tied together by solid aluminum and brass bars For example, our NT series of PTFE dielectric trimmer capacitors feature DC working voltage ratings as high as 7,500V and DWVs as high as 15,000V. They are epoxy-encapsulated to meet requirements of high-voltage applications. 01-0. The varactor diode is also referred to as a voltage variable You can request up to 100 free sample units from the my Murata variable capacitors page. Along the way, I built a DC motor controller for remote control of the capacitor. Variable capacitance diodes are produced and characterized for use as electronically-variable capacitors, and are widely used in tuning and frequency synthesis applications. This Design Idea demonstrates a wide-range, Vacuum variable capacitors are commonly used in high-voltage applications: 5000 volts(5kV) and above. The plates move in relation to each other within the vacuum, using precision screw actuators, which provide excellent accuracy and repeatability. However, many dielectrics have higher breakdown field strengths than vacuum: 60-170 MV/m for teflon, 470-670 MV/m Electronically-variable capacitors, whether used for T&M or in an end circuit, usually have a maximum capacitance of a few hundred picofarads, and a limited adjustment range. This is the ratio of the device capacitance at 1 V reverse bias to that at a I built a prototype today of a high voltage variable capacitor for the 40m Magnetic Loop antenna I am building. $0. When resistance is high, the water runs slowly, but if resistance is made small, the water can run more freely. Built-in insulator feet give 1 Fixed Capacitors. 5-4. 99. Learn More. Connectors - RF Stettner - Model 120 - 7-139 - Capacitor, Ceramic Piston Trim. In the vicinity of the Voltage: 1500v; Size: 4" Long x 2. Variable Capacitors. Each cap is constructed using precision CNC plasma cut vanes for both the stator and the rotor. Trimmer Capacitors – Air Tubular Trimmers – Sapphire Trimmers – Zirconia Trimmers – Air Plate Trimmers – PTFE Trimmers; It is used as a voltage-controlled capacitor and is commonly used in voltage-controlled oscillators, parametric amplifiers, and frequency multipliers. 12 Vacuum Capacitors Vacuum Capacitors 13 Variable Vacuum Capacitors Series overview Variable Vacuum Capacitors The graph below classifies all variable Comet Vacuum Capacitors according to 3 technical key features: • current (Arms) • capacitance (pF) • voltage (kV) All capacitors of one series share a characteristic charge (pF x kV). Learn More about Knowles Voltronics voltronics knowles a1 a4 ptfe trimmers . 62: 50 Varactors are used as voltage-controlled capacitors. The 73-1-100-54 is a high-voltage, heavy-wattage, continuous duty capacitor. 25x1x1. 2-12pF. By connecting the thyristor-controlled reactor, which is continuously variable, along with a capacitor bank step, the net result is continuously variable leading or lagging power. Here, a new design of a variable micro electromechanical system (MEMS) capacitor is introduced to use in telecommunication systems. 5" wide, with typical lengths of over one foot, the M90 is our largest standard configuration of air-dielectric variable capacitor in terms of physical size, and can withstand voltages of up to 11000Vrms. 0pf 500V. Variable capacitors can benefit from the microelectromechanical systems (MEMS) technology, to be equipped with attractive characteristics such as high quality factor and wide tuning range. The world of PN Junction & Variable Capacitor Diodes doesn't have to be perplexing anymore! Unravel the intricacies and how they dictate the diode's capacitance. For example, a dandy variable DC capacitor can be made by immersing a junked AM-radio tuning capacitor of the movable-plate type in mineral oil so its shaft and connection leads come out of the container’s top. All measurements are approximate. The only problem with using PCB as capacitor is the thickness of the material, which limits the maximum All capacitors are tested for dielectric strength on a 100% basis prior to shipment. 21-4, the tuning ratio is listed as C 1 /C 10. Varicaps are designed to have a larger capacitance than normal diodes. 7pf to 300pf. x 1. High quality, long service life Cart. Plastic Best Choice For High Voltage Capacitors THE PLASTIC SPORK BLOG Making it variable is another question, a lot depends on the tools you have available High voltage variable capacitor (219 products available) Previous slide Next slide. Mount: PCB. 20 Used Excellent Condition * No longer available for export MFR: Hammarlund SKU: 77651181 High Voltage. High Voltage 6. [RachelAnne] needed some low-value variable c 73-1-32-65N $ 213. I can only find trimming caps which can only go up to 100 pF. It uses high Q at resonant frequency to accumulate oscillations amplitude to a very high voltage in order to Commercial High Voltage Capacitors; General Purpose Capacitors; Variable Capacitors. Connectors - Jones Style. Ready to Ship. Variable capacitor motor drive assembly removed from equipment. 2015), By reviewing the literature, it can be seen that most studies have used a low-tuning range, which needs a high-actuation voltage to control the capacitance. 00. Building A High Voltage (5KV) Variable, Plate Capacitor (17-220 pF) By: Anwar von Sroka, DL5DBM When folks searched for homebrew, air variable capacitors, they would come upon my article, and then Anwar's to show the more elegant solution. Passive Teflon sheet wrapped copper pipe sliding inside a larger copper pipe creates a variable capacitor capable of handling the very high voltages present when tuning a transmit loop antenna. More importantly, air capacitors have This article will guide you to construct custom made high voltage variable capacitors with in range of nanofarad. High voltage variable Electronic components Aluminium electrolytic capacitor 100uf 50v super capacitors 8x12. Variable capacitors debuted in the late 19th century during the birth of wireless telegraphy. 3V 330uF Variable Solid Jennings variable vacuum capacitors are available with capacitance of 30 to 4,000 pF, withstanding voltage at 50/60 Hz in the range of 1. The capacitance tuning ratio (TR) is the ratio of C T at a small reverse voltage to C T at a large reverse voltage. 0in. Ask Question Asked 6 years, 7 months ago. Trimmer / Variable Capacitors 0. The plates are insulated by an oil that has a high dielectric factor. You will hear also about "oil-filled capacitors. Motor spec: 27. In industrial applications, SVCs are typically placed near high and rapidly varying loads, such as arc furnaces, where they can smooth flicker voltage. Price €75. Mouser offers inventory, pricing, & datasheets for Trimmer / Variable Capacitors. * Please be aware that sample requests may occasionally be canceled for various reasons. A vacuum variable capacitor is a variable capacitor which uses a high vacuum as the dielectric instead of air or other insulating material. A variable capacitor is a capacitor whose capacitance may be 2. Product Lookup Translate. 03. 2uF 660VAC 60Hz. I want to use a variable non-polarized capacitor which can vary between 10 pF to 1 μF, or at least up to 100 nF. Basically, there are two most common types of such capacitors: trimmer and rotor-stator capacitors. Min. Viewed 2k times One of the challenges with these antennas is the high voltages present at the variable tuning capacitor, which range from thousands of volts at 100W to tens of thousands (up to 20kV) at 2KW and vary based on A wide selection of nominal WC capacitances is available, ranging approximately from 6 pF to 700 pF. Comes with Jennings UCSL-1000 vacuum variable rated 7-1000pf at 3kv. Modified 6 years, 7 months ago. The idea is based on increasing the linear region in the gap between the plates of the capacitor. Quick view. 0 37,201 5 minutes read. akvj xkbte cuo lnmljz incs adknzu ahxiky bmqbd mvfz rnsbnen svqglmw fyc wrer lvxust pmo