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Built ruggedly for everyday use, the MS8217 digital multimeter is perfect for reliable & stable electrical testing.
For high humidity environments, Vishay Roederstein MKP1847 series metallized polypropylene AC filtering film capacitors withstand temperature humidity bias (THB) testing.
Changed power at Q5 and Q6 to be Vdd instead of V_led. This means that Q5 and Q6 don't have to switch on every AC cycle. This did get rid of a large delay in getting the mosfet turned on. Now there is a problem with some narrow pulses on the falling edge of the rectified AC waveform. I'm guessing that this is due to the mosfet not staying turned off as the source voltage drops.... thinking about adding a small cap or resistor from gate to source to make the gate voltage less susceptible to transient voltages coupled through drain-gate or source-gate capacitances. This is a classic issue with low-side drivers, but it's harder to say if this is a problem with high-side drivers.
All three LED boards connected to the supply voltage bus. Each board does PWM and there's a magic frequency that creates a noticeable (audible + visible) beat-note. Adding some capacitance helps. Should have been on the PCBs, but it might have worked without it.
The PmodCDC1 is a capacitive sensor that uses the Analog Devices AD7156. By communicating with the chip via I2C, users can set the Pmod for an adaptive capacitance threshold that changes with the environment or set static thresholds that only trigger when a certain capacitance is reached.
Oscilloscope screen-shot, displaying the following signals of the 74HC373 (U65) (see probe connections here):
• channel 1 - output enable
• channel 2 - latch enable
• channel 3 - D0 (latch input 1)
• channel 4 - Q0 (latch output 1)
Upon observing the shape of the edges, I realised that the capacitance of the oscilloscope probes was interfering with the quality of the measurements. To correct for this, I later switched each of them over to the 10x setting.
Capacitive touch screen is the 2nd most popular type of touch screens on the marketplace. In a surface industrial touch screen monitor, a translucent electrode layer is put on top of a glass board. That really is subsequently covered by a protecting covering. When a vulnerable finger touches on the track screen, it reacts to the static electric power of their body. Some of the electric charge transports out of the screen to the user. This decline in capacitance is detected by sensors situated in the four corners of the screen, letting the control to determine the touch point. Capacitive touch screens can be activated by the touch of skin or some stylus holding a electric fee.
Straighwire Symphony II, DIY interconnect unbalance cable assembly.
Capacitance of 0.5 mts coaxial interconnect cable
Redwood City, CA
10 November 2024
Rodenstock 50mm/4.0 HR Digaron-W lens (@ f/6.3), Phase One IQ4-150 digital back, Cambo 1250 camera (vertically shifted -23mm).
The large amount of vertical shift required to keep the tall antenna mast fully in the frame while maintaining its geometry pushed the 50mm Rodenstock lens to the very limits of its image circle, Hard vignetting of the upper corners is visible in the full sensor image, but fortunately the composition benefited from a narrower aspect ratio that cropped out the blackened corners.
KNBR is a 50KW "Class A" (formerly "clear channel") mediumwave (AM) rado station broadcasting on 680 KHz, serving the San Francisco Bay area (and, at night, most of the west coast of the US). Opened in 1922, It was originally known as KPO, (later KNBC, and still later KNBR), and soon became the flagship station for the National Broadcasting Company (NBC)'s western radio network. It is currently owned by Cumulus Media and broadcasts a sports format.
Mediumwave (AM) broadcast radio uses lower frequencies than other kinds of modern broadcasting and so requires much larger antennas (generally getting larger and larger as the frequency gets lower on the dial). This often entails highly customized antenna designs engineered for the particular site and station frequencies. For most radio stations (FM, TV, etc), the towers are there simply to get the relatively small antennas up high, but for AM stations like KNBR, the towers generally ARE the antennas.
The taller tower (550 feet) at right is the main KNBR antenna, built in 1949. It employs an unusual "pseudo-Franklin" design; it is actually an array of two antennas stacked one atop the other. The lower section, 400 feet tall, is insulated from the ground and fed from the bottom. It also carries a feedline to the upper 150 foot section, which is insulated from the lower section (visible as a narrowing of the tower just above the second set of guy lines from the top). The large (50 foot) diameter "capacitance hat" at the top (reminiscent of the famous Parachute Jump at Coney Island) electrically lengthens the top section to match the bottom, saving about 250 feet of additional height.
This distinctive stacked dual antenna arrangement is used to lower the radiation angle of the antenna, concentrating transmitted power to the "ground wave" and reducing energy that would otherwise be sent upward into the sky.
The smaller (300 foot) freestanding mast in the background left is not in current use but once had a FM broadcast antenna at its top. The tower can be used as an emergency spare antenna for KNBR during maintenance of the taller main antenna.
The antenna is in the final approach and takeoff flightpath for SFO airport's runways 28L/R (and 10L/R), and so the site has special markings to warn pilots of a collision hazard. In addition to the usual tower lights and red/white paint, 3-dimensional "HAZ" warnings were installed around the field. These are easily visible in areal photos; see, e.g., earth.google.com/web/@37.5471204,-122.23429544,0.73120256...)
No emulsions were harmed in the making of this image.
P0003559
Digital Multimeter features 3¾ Digital multimeter with maximum reading of 3999 ,DCA,ACA,resistance,capacitance,frequency and temperature.visit www.falconindia.biz
* Huaercai AUDIO&VIDEO CABLE * ★ 3C2V Coaxial TV Cable
Specification:
OD: 5.0mm
Conductor: ( 0.5 mm+ PE Foem + AL Foil + 0.10*32 Braid CCS)J
acket: PVC
Connector:Nickel plated, F connector gold plated
Features: This product uses wire 75 - 5 ( 2P) 75Ω coaxial cable, wire core ultra - low capacitance PE foam insulation layer and the inner 4N oxygen - free copper conductor, both ends of the special configuration
Application: Used for audio/video signal transmission between the camcorder and VCD, DVD, AMP,TVs,etc.
Packing&Delivery: Polybag with carton box, FOB SHANGHAI, 3 - 20 days according to your quantity
Payment: TT
Coaxial cables are also available in different RG types. RG stands for Radio Guide, or Radio Grade and is a term that is used when sending Radio Frequency (RF) signals down a coaxial cable. 75 ohm coaxial cable comes in several sizes with the most common types being RG-179, RG-59, RG-6, RG-7, and RG-11. An RG-179 & RG-59 cables are the most commonly used coax because they are small in diameter and easy to work with. The RG-11 cable is the largest in diameter and harder to work with. The RG-6 and RG-7 sizes are between the RG59 and RG11. The difference between the RG types are not just size, but also the attenuation characteristics and therefore the transmission distance.
* Huaercai AUDIO&VIDEO CABLE * ★ 3C2V Coaxial TV Cable
Jason and I attempted to take Kirlian photographs of coins. Basicly Kirlian photography uses electricity instead of light to expose film. Originally, people thought this exposed auras and chi, nowadays we know it's just a trick of capacitance and moisture. We generated about 70 kV using a television flyback transformer and zapped a quarter sitting on photographic paper, the coronal discharge from the coin exposed an image of its underside, on the upper left image you can see some fuzzy tendrils from the corona as well.
This 3D stereographic photo is of the CardioMEMS device, an implantable pressure sensor that wirelessly measures pulmonary artery pressures without requiring any batteries. It is used for heart failure patients to monitor their hemodynamics and estimate their volume status. This aids in prophylactically adjusting diuretics and heart failure medications before a patient becomes symptomatic and has to present to a hospital for a heart failure exacerbation. Reducing hospitalizations and HF exacerbations would aim to reduce mortality and improve quality of life.
The device is pretty amazing as it is very small and works indefinitely without batteries. The main component is a 15mm x 3.4mm x 2mm rectangle with two nitinol wire loops on each side that extend the length of the device to 4.5cm. Nitinol is a metal alloy of nickel & titanium that exhibits shape memory and superelasticity. Nitinol is commonly used for stents and other medical devices as it is biocompatible and folds up nicely in a tiny catheter before being deployed in the body where it expands to its full size and shape. This anchors the device in the distal pulmonary artery.
Its theory of operation is exceedingly simple in terms of design. It consists of a three dimensional coil of wire and two metal plates on two wafers of fused silica encased in silicone. The coil is produced through electrodeposition of gold onto a silica wafer in a vacuum chamber. Fusion bonding is used to join the silica wafers. The coil of wire forms an inductor and the two metal plates act as a capacitor in physics & electronics terms. This arrangement connected in a parallel loop forms a resonant LC circuit (L=inductance, C=capacitance). Depending on the capacitance and inductance of the components, the circuit will oscillate at a perferred resonant frequency. The capacitor in the CardioMEMS is exposed and very thin allowing the silica crystal and metal plates to deform with changes in pressure from the blood within the pulmonary artery. Changing the distance between metal plates of a capacitor changes its capacitance value thereby changing the devices resonant frequency. An external machine can ping and excite the coil with various electromagnetic radio frequencies until it is able to find its resonant frequency. By working backwards, the measured frequency can be converted into an estimated capacitance which can be correlated to an estimated pressure measurement.
The device is placed during the right heart catheterization (RHC) procedure when the physician threads catheters from a patient's veins through the right atria, past the tricuspid valve, through the right ventricle, and finally past the pulmonary valve into the pulmonary artery. Fluoroscopy or video x-rays along with radiopaque contrast are used to visualize the blood vessels and guide the catheters to their destination. During the RHC, the cardiologist will use a Swan-Ganz catheter to measure the actual pressure and calibrate the device's measured pressures to actual pressures.
doi.org/10.1177/1753944719826826
This photo is in 3D parallel view. More Instructions for viewing 3D images: www.3dphoto.net/text/viewing/technique.html
Stereo Viewer for all my photos: jongames.com/stereophoto/
I think this is a BaTiO3 (barium titanate), but not sure. At least, it has high dielectric constant. Diameter of the disk is 32 mm, thickness is about 3.5 mm (not thick enough for 20 kV working voltage).
Capacitance of the capacitor (was): 4.7 nF, 6.3 kV. I hope by stacking few disk to achieve higher possible voltage in order to prevent premature damage.
Final assembled structure with components. This is the 2nd generation device, and uses a dual 2016 battery holder which is low profile, but unfortunately 2016 batteries didn't provide enough juice for a nice bright LED flash. The little switch is present just to be able to 'turn off' the whole circuit so that the battery is completely open, and no tiny bit of leakage capacitance across he MOSFET can drain it over time. Probably unnecessary, but what the heck.
DoITPoMS, University of Cambridge
The light metal layers are shown edge on alternating with the ceramic layers. This sandwich configuration maximises the area of contact and so capacitance of the MLC. Thin ceramic layers are also desired to maximise capacitance. See the equation for a parallel plate capacitor.
System
BaTiO3 Ag/Pd
Composition
BaTiO3
Reaction
Processing
A barium titanate slurry is tape cast to give a thin sheet which is dried and a paste or ink containing the Ag/Pd powder is screen printed on it. The large sheets are then diced, stacked and co-sintered together.
Applications
Any electrical circuit or product requiring capacitors i.e. most of them including TVs, videos and computers.
Sample preparation
Polished but unetched.
Technique
Reflected light microscopy
Length bar
TBC
Contributor
Prof W E Lee
Organisation
Department of Engineering Materials, University of Sheffield
The PmodCDC1 is a capacitive sensor that uses the Analog Devices AD7156. By communicating with the chip via I2C, users can set the Pmod for an adaptive capacitance threshold that changes with the environment or set static thresholds that only trigger when a certain capacitance is reached.
CT81 HV Disc Ceramic Capacitor 2KV~50KV, 10pf~50000pf
CT81 High Voltage Disc Ceramic Capacitor, High Voltage Disk Ceramic Capacitor, HV disc ceramic capacitor, 20KV radial disc ceramic capacitor, 30kv axial ceramic capacitor, 50kv axial disc ceramic capacitor
Manufacture Supply CT81 High Voltage Ceramic Capacitors
Application,
CO2 lasers
High voltage pulse generator
X-ray power supply
X-ray high voltage generator
NDT (Non-destructive testing)
Airport security equipment
High frequency & high voltage power supplies
Medical power supply
Military
Rated Voltage: 1000V, 2000V, 3000V, 4000V, 5KV, 6kv, 6.3KV, 8KV, 10KV, 12kv, 15KV, 20KV, 25KV, 27kv, 30KV, 35KV, 40KV, 50KV
Capacitance: 100pf (101), 120pf (121), 200pf (201), 220pf (221), 270pf (271), 330pf (331), 390pf (391), 470pf (471), 500pf (501), 510pf (511), 560pf (561), 680pf (681), 750pf (751), 1000pf (102), 1200pf (122), 1500pf (152), 2000pf (202), 2200pf (222), 2700pf (272), 3000pf (302), 3300pf (332), 3500pf (352), 4000pf (402), 4500pf (452), 4700pf (472), 5600pf (562), 6000pf (602), 6800pf (682), 10nf (103), 20nf (203), 22nf (223), 47nf (473)
Characteristics:
Operating Temperature Range: -25C to +85C
Rated Voltage (V): 1 KV -50KVDC
Capacitance Range: 100pF -50,000pF
Temperature characteristic: N4700(DL), UJ, SL, YL, BN,Y5P, Y5R, X7E(X7E), X7F(X), X7R(X7R), Y5S(S), Y5T(D), Y5U(E), Y5V(F)
Test Voltage: 2 times of the rated voltage.
Dissipation Factor (tan): at 1 KHz, 1+-0.2 Vrms, 25C
Y5P, Z5U: tan<=2.5%
Z5V: tan <=5%
Insulation Resistance: 10,000 M or 200 M whichever is the smaller
General Specifications:
6kv: 100pf, 470pf, 1000pf, 2200pf, 3300pf, 4700pf, 10000pf
8kv: 18pf, 100pf, 500pf, 680pf, 1000pf, 10000pf
250vac 8kvdc: 220pf, 470pf, 1000pf, 2200pf, 4700pf
10kv: 10pf, 22pf, 33pf, 50pf, 100pf, 135pf, 220pf. 330pf, 500pf, 680pf, 1000pf, 2200pf, 3300pf, 4700pf, 5000pf, 10000pf
15kv: 30pf, 50pf, 100pf, 150pf, 220pf, 330pf, 470pf, 500pf, 680pf, 1000pf, 1500pf, 2200pf, 3000pf, 3300pf, 4700pf, 10000pf
20kv: 20pf, 100pf, 110pf, 150pf, 220pf, 330pf, 470pf, 500pf, 680pf, 1000pf, 1500pf, 2200pf, 3000pf, 5000pf, 6000pf, 10000pf
25kv: 500pf, 1000pf, 10000pf
30kv: 100pf, 150pf, 220pf, 330pf, 470pf, 500pf, 680pf, 1000pf, 1500pf, 3300pf, 4700pf, 5000pf, 10000pf
35kv: 500pf, 1000pf, 1500pf, 2700pf, 3000pf, 4500pf, 6000pf
40kv: 30pf, 100pf, 470pf, 4700pf, 6000pf
50kv: 30pf, 470pf, 500pf, 560pf, 750pf, 1000pf, 10000pf
Alternative replacement and direct cross of AVX, TDK, HVCA, CKE, Vishay, Morgan Ceramics and etc...
Vishay’s new online aluminum capacitor selector tool quickly sorts through the company’s entire offering of aluminum capacitors based on a number of specifications, including capacitance, voltage, form (e.g. axial, radial, SMD, snap-in or screw terminal), case size, maximum temperature, useful life, and style (e.g. low profile or blister tape on reel). (For hi-res version, select "View all sizes" from Actions pulldown menu above.)
Straighwire Musicable II, DIY interconnect semi-balance cable assembly.
2 inner wires (white) connected to center pin of RCA, other 2 inner wires (black) connected to the outer shell of the RCA, and mass braid only connected to the outer shell of the RCA at the source end.
Capacitance of 0.7 mts interconnect coaxial cable
Erith High Voltage Laboratory. The seventh stage insulator (left) and capacitor (right) being fitted. Eventually there will be 16 stages of 200 kV each.
The set was built by Ferranti (Manchester) using these capacitors made by BICC Capacitors (Ellesmere Port). There was a deal whereby BICC Cables Ltd would buy the capacitors direct from BICC Capacitors Ltd, so Ferranti didn't get to add their mark-up on that part of the project cost. After early reliability problems with these capacitors, the mineral oil in them was replaced with castor oil; after that, they were trouble-free at 200 kV, and as an added benefit their capacitance was found to have been increased from 320 to 350 nanoFarads each, which improved the performance of the set.
* Huaercai AUDIO&VIDEO CABLE * ★ 3C2V Coaxial TV Cable
Specification:
OD: 5.0mm
Conductor: ( 0.5 mm+ PE Foem + AL Foil + 0.10*32 Braid CCS)J
acket: PVC
Connector:Nickel plated, F connector gold plated
Features: This product uses wire 75 - 5 ( 2P) 75Ω coaxial cable, wire core ultra - low capacitance PE foam insulation layer and the inner 4N oxygen - free copper conductor, both ends of the special configuration
Application: Used for audio/video signal transmission between the camcorder and VCD, DVD, AMP,TVs,etc.
Packing&Delivery: Polybag with carton box, FOB SHANGHAI, 3 - 20 days according to your quantity
Payment: TT
Coaxial cables are also available in different RG types. RG stands for Radio Guide, or Radio Grade and is a term that is used when sending Radio Frequency (RF) signals down a coaxial cable. 75 ohm coaxial cable comes in several sizes with the most common types being RG-179, RG-59, RG-6, RG-7, and RG-11. An RG-179 & RG-59 cables are the most commonly used coax because they are small in diameter and easy to work with. The RG-11 cable is the largest in diameter and harder to work with. The RG-6 and RG-7 sizes are between the RG59 and RG11. The difference between the RG types are not just size, but also the attenuation characteristics and therefore the transmission distance.
* Huaercai AUDIO&VIDEO CABLE * ★ 3C2V Coaxial TV Cable
RG59 CCS with Standard Power Connectors 500ft Black quality cable ensure you'll have great video and consistent power. Our industrial grade coaxial cable has 95% shielding and a tough casing. This zip wire is supplied in a 'reel-in-the-box' contractor-preferred pull box. This zip wire is perfect for running with the 2/18AWG power cables. power and video simultaneously and enables you to facilitate a clean install.
Features:
75 Ohm Video Signal Transmission
20 AWG solid center conductor produces very low insertion loss
Common size cable can be easily terminated
Speaker Test: 4000 VAC
Capacitance: 54pm/m
Velocity of Propagation: 85%
Applications:
CCTV
Video
Premise wiring
Security
www.1000ftcables.com/rg59-ccs-with-standard-power-connect...
It works ! Amazingly, a solenoid shape antenna made of silver coated textile gives better results than our good old copper plates... We should patent that but i think the conductive thread antenna are now classic in patent websites :)
It works ! Amazingly, a solenoid shape antenna made of silver coated textile gives better results than our good old copper plates... We should patent that but i think the conductive thread antenna are now classic in patent websites :) Capacitance range is up to 30 cm...
Vishay is now offering its popular low-ESR TR3 high-capacitance, high-voltage molded tantalum capacitor in the new W case (EIA 7361), which measures 7.3 mm by 6.0 mm, with a height of 3.45 mm, and allows for capacitance and voltage range expansion beyond the existing A through E case sizes. (For hi-res version, select "View all sizes" from Actions pulldown menu above.)
Voltage range :1kV to 1600kV
The SF6 gas insulated standard capacitor are widely used in high voltage capacitance and dissipation factor tan delta measurement .The applications include insulating materials of and electric apparatus,**** transformer .The applaication include insulating materials of and electric apparatus **** transformer ,power cable ,motor,generator,high voltage capacitors,high voltage bushing ,instrument transformer.
Crypton Magmaster tester, with add-on panels with gauges etc, for bolting on the sides of the main unit. Variable speed motor drives in either direction, tachometer (centre zero). Two spark gaps, with a third one on one of the panels. Degree scale for strobe light use, with a spinning pointer (not visible here). Various rotating ignition hardware can be tested, with mounting adaptors and shafts as required. The broken gauge is capacitance tester. Where can I find a replacement?
This dual RG6 Bare Copper dual shield dual bare copper 500' Black 3GHz commonly used 75 Ohm cable can be used in applications where cable assemblies must be built in the field. The 18 AWG Solid dual Copper Center Conductor results in a cable with very low attenuation properties.
Features:
75 Ohm video signal transmission
18 AWG dual Bare Copper Center Conductor produces very low insertion loss
Common size cable can be easily terminated
Speaker Test: 4000 VAC
Capacitance: 54pm/m
Velocity of Propagation: 85%
Operating temperature of -40 to +80 degree C allows use in a wide range of applications.
Applications:
CCTV
Video
Premise wiring
Security
www.1000ftcables.com/500ft-rg6-bare-copper-dual-shielded-...
The PmodCDC1 is a capacitive sensor that uses the Analog Devices AD7156. By communicating with the chip via I2C, users can set the Pmod for an adaptive capacitance threshold that changes with the environment or set static thresholds that only trigger when a certain capacitance is reached.
More or less finished. Sealed the slot and filled either side of the can with hi temp silicone. The top cap of the can was made from the plastic backing of a Coleman lantern pump with a #10 screw through it. A nut holds the screw in place. A #10 ring terminal is crimped and soldered to the + side of the cap and that is slipped over the screw. The original Velosolex connector then fits over the screw atop the ring terminal and the whole works is held in place with a nylock nut.
Will let the thing sit to allow the silicone to cure but I get a good reading from the capacitance meter that everything went together right.
This is one of the two primary capacitor banks from my Tesla coil. Strings of off-the-shelf capacitors are soldered together to make a single capacitor of the desired capacitance and voltage rating (several kV !!).
A pair of BNC-terminated oscilloscope probes, perfect for use with the Analog Discoveryâ„¢ in conjunction with the Discovery BNC Adapter.
A pair of BNC-terminated oscilloscope probes, perfect for use with the Analog Discoveryâ„¢ in conjunction with the Discovery BNC Adapter.
Welcome to www.kkulikov.com - Photos and footage for mass media, advertizing agencies and design studios, and also private designers and bloggers.
My portfolio on iStock.
This photo on iStock.
Capacitance vs timer value for discharging a capacitance thru a large resistor and measuring the time to reach below 1.1V band-gap reference on AIN1. The sensor is a capacitive relative humidity sensor, nominal capacitance 240pF at 25C 60% Hrel and 100kHz resonance frequency. Clearly this setup differs a lot from that.
The sensor capacitance during measurement was estimated with value interpolation against the cap-only data.
Caps data: 20pF ceramic capacitors in parallel.
Sensor+caps: sensor + 20pF ceramic capasitors in parallel.
"Audiophile-Grade" Cables Have Finally Arrived For Car Audio
With the Comice Silver Interconnect, Pear Cable has made a leap forward by utilizing appropriate home audio cable technology to bring a crystal clear sound to car audio.
Pure Silver Signal Conductors
99.99% pure silver, annealed to prevent microcracking, for "audiophile-grade" signal transfer. Don't settle for sound degrading silver-plated copper. Pure silver conductors significantly reduce corrosion and the harmful silver/copper metal interface is eliminated, for the ultimate in sonic clarity and accuracy.
Triple Noise Reduction with TRIBODeadTM
Three levels of noise reduction including the world's first car audio cable to have TRIBODead triboelectric noise killer.
•TRIBODeadTM conductive polymer layer dramatically reduces the amount of triboelectric noise created. Pear Cable is the world's first company to bring this technology to car audio cables. Triboelectric charges are created when vibration causes two different materials to rub against each other in a cable. TRIBODead™ virtually eliminates this noise caused by vehicle vibration for a cleaner sound and lower overall noise floor.
•Twisted Pair conductors help prevent EMI noise from getting into your sound system. EMI is generated in your car as current travels through the chassis of the vehicle. Twisted pair conductors are essential for eliminating alternator whine.
•Spiral Serve Shield. Radio Frequency Interference (RFI) rejection is accomplished with a silver plated spiral served shield, grounded at one end only. The metallic shield acting in conjunction with the TRIBODead™ layer offers 100% RFI coverage.
Teflon Air Tubes
Teflon air tubes are twisted with the Teflon insulated wires to lower the capacitance of the cable. A technique generally reserved for high fidelity home audio cables, Comice Silver Interconnects elevate car audio cables to a new standard. Hear all the punch you desire without the fatigue.
Portal - AudioShop ( Chandra )
Hotline : 08161956046, 021-70505183
e-mail : tjc_12@yahoo.com
Don't know if the caps are still good, but this looks like a painless way to get a lot of capacitance the easy way.
I had to find out the hard way that my Kitchen Lights boards lack a lot of smoothing capacitance on the LED driver supply lines. Therefore I made this board, which just attaches to the bus in between the main PCBs and should take care of the problem.
A lot later I realized that one layer of it it looks somewhat like a happy face ;-)
View of the high voltage cap, plates partially closed. Some of the stator plates had been removed to adjust the maximum capacitance.