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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.
My refurbishment on this Revox A77 Mk1 circa 1969 is now complete. This was the more desirable high speed version (15 & 7.5 IPS). The old Tantalum capacitors replaced with modern electrolytics, old Rifa spark suppressors replaced along with all new trim pots and some high wattage resistors. New brakes and hubs fitted. Still running on the original hub motors and capacitance motor. I’ve treated it to brand new RMG LPR90 tape and performed a full recalibration. I may replace the heads in the future however they still have plenty of life left in them.
Breadboard prototype of a capacitance meter.
The capacitor to be measured is placed in a 555 oscillator circuit and an Arduino measures the frequency. This prototype has no display.
A circuit bending work station.
1. Resistance pots (4k7, 100k, 1m)
2. Capacitance - 12 caps selector
poly 47-pf, 100-pf, 470-pf, 1-nf, 4n7 nf, 10-nf, 100nf, 1-uf, 1uf
elec 1uf, 4.7uf, 10uf, 100uf
3. LED
4. Signal tracer simply a 1w amp maplin kit to trace audio signal in a circuit.
Visit my site for more info: kickme.to/lightningstalker
This shows what it looks like inside a metal can capacitor. They're used a lot as motor start/run capacitors and in microwaves.
This one is a Magnetek 24uF 400VAC unit from some sort of HID lamp ballast. I opened it up with the intention of removing the internal bleeder resistor. It turned out that there was no obvious bleeder resistor anywhere. The capacitor itself has 5-10 megohms of leakage resistance. This is probably from doped dielectric or more likely the core it's rolled on.
This one was opened with a sawsall which is the messiest way of doing this. The oil and metal shavings fly everywhere. This was the first one I opened so I learned my lesson.
I took this picture after the oil was poured out. What you'll probably notice immediately is that the can is oval shaped but the capacitor itself is actually a cylinder. The reason for this is because if the capacitor were to overheat, the pressure that builds up inside has to have somewhere to go. When a little pressure builds up, it bends the can outward which pulls the seam apart and lets it vent to the atmosphere. They used to make them cylindrical and because they didn't expand, a lot of pressure would build up before the can ruptured and they would often explode.
I also posted a picture of the capacitor after it was removed from the can.
This is a small secondary. 2 inch coil form, 11 inch winding height, 32 AWG magnet wire. 1176 total turns, secondary H/W ratio 5.2:1, secondary coil capacitance 4.2pF, secondary coil inductance 12.8 mH. It is coated with 8 coats of DEFT gloss lacquer.
Dielectric Thermal Analysis accessory is a material characterization technique similar to dynamic mechanical analysis except that on oscillation electrical field (AC field) is used in place of a mechanical force (stress) and the oscillation strain is a stored charge (Q) in the sample. Q is measured as its derivative dQ/dt = AC current. DETA measures the degree to which the sample is storing a charge (capacitance) or passing the charge (conductance) through its bulk, which reflects the orientation or mobility of random dipoles. This technique is especially powerful for characterizing polar materials such as PVC, PVDF, PMMA, PVA, and for monitoring curing kinetics of materials such as epoxy and urethane systems. The wide range of frequencies available in DETA (up to 30 MHz) also extends the measurement range far beyond traditional dynamic mechanical analysis.
Reference® RIC01 instrument cable (LIVE ACT series)
Designed for LIVE applications, RIC01 instrument cable features outstanding wide and detailed frequency response, fast transients preservation, superior noise rejection, extreme flexibility, and greater mechanical stress relief. It is therefore recommended to all musicians who demand the ultimate in performance and reliability also for RUGGED STAGE and daily touring use. Unsurpassed TRANSPARENCY and clarity make this cable ideal for passive guitar pickups, allowing signal to be rich in dynamics and harmonics, and noise-free as well. Stranded inner core construction makes this cable more flexible, gives mechanical strength and avoids twisting, tangling and any shape-memory retention. Double braided copper shield and conductive sheath inside the screen provide strong protection against hum or noise caused by movement, besides making this cable sturdy and durable. Purest oxygen free copper conductor and low capacitance design provide higher pickup resonant peak and a brighter overall sound, preserving the unique personality of your tone. Hand assembled with highly reliable machined gold-plated plugs, RIC01 is your best guarantee for great-sounding live act.
Cable Specs
Inner Core: Stranded Red CU 42x015 Ø AWG18
Insulation: FOAM PE Ø 3,0 mm
Shield 1: PVC Semiconductor Ø 3,0 mm
Shield 2: Double Braided Red Copper
Jacket: Compound PVC Ø 7,6 mm
Bending Radius: 8x cable Ø
Impedance: 51 Ω
Capacitance cond/shield: 24 pF/ft
--------
stereolist.com/cables/analog-interconnects/balanced/puris...
Purist Audio Design, Proteus Provectus XLR Fluid Dampened and enhanced design in 1.5M pair with nice factory Bag.
Current Cable in Line Up.
Proteus Provectus Cable Line (from PAD web site):
Purist Audio Design is proud to introduce the Proteus Provectus line of cables. The original Proteus was a very popular line of our products. We decided to reintroduce the Proteus; however, this is by no means is the Proteus of old. The Proteus Provectus is a completely new design! The word "Provectus" is Latin for advanced, and that is exactly what this line of cables is!
The Proteus Provectus uses a unique solid-core construction with our proprietary fluid shielding. Using this unique design, the cables provide amazing spatial depth, with a sweet top-end, and a very deep controlled bottom end. We designed this line of cables to fill the performance gap in between the Venustas and Fluid Dominus.
Great sounding balanced cables // trade gladly accepted and makes this a great opportunity to upgrade your cables and sound.
Great deal and wonderful sound!
Serial Number: 10019757 in like new condition (see pictures).
Reprinted from Purist Audio Design Web Site:
Proteus Provectus Interconnects:
The Proteus Provectus line of Interconnects are available in Single-Ended (RCA) and Balanced (XLR) configurations. If your system demands a custom configuration, please contact us. We're able to custom-build to fit your needs!
All Proteus Provectus cables come packaged in a handsome soft case.
Technical Specifications
Design Goals: High performance to cost ratio
Conductor: Solid Core
Metals: Copper Single Crystal
Shielding: Foil with drain wire
Dielectric: PVC
Dampening Material: Fluid
Gauge (effective): 22 AWG
Capacitance:
170 pF/m ±15% (pin-to-shield)
Resistance: 13.2 mΩ/m (conductor)
Estimated Break-In Time: 200 Hours
Cable Diameter: Single-Ended: 1/2" OD (One Channel)
Balanced: 5/8" OD (One Channel)
Material Treatment: Triple (3x) Cryomag©
Best to call David www.weinhartdesign.com with questions in Los Angeles Showroom 310-472-8880 or on my cell after hours and weekends 310-927-2260.
Weinhart Design has lots of other items new and used and if you're in Los Angeles or visiting please accept my invitation to experience our World Class Audio Showroom and please visit our web site @ www.weinhartdesign.com
We are always interested in purchasing quality Audio and Video items, CD & LP collections and most quality trades are welcomed.
All sales out of California are State Sales Tax exempt.
California State Sales Tax of 9.75% applies for items picked up or shipped to a California address.
We accept payments by Bank Wire Transfers without fees and is the only form of payment on all sales out of the U.S. and Canada. We prefer this method of payment and also makes shipping to addresses other than billing agreeable.
VISA, MC and Papal are gladly accepted within the U.S. and Canada as long as the charge is approved and shipping to the billing address on record and adds 3% to cover costs.
Please call me directly in my world class showroom in Los Angeles weekdays @ 310-472-8880 or any reasonable time on my cell including weekends @ 310-927-2260 and I can answer your questions and help you with all of your new and pre owned needs.
R1618HDTV video cables are used in critical digital and analog video connections and high quality applications (like HDTV/SDI ) in pre/post production facilities and network studios.
CONSTRUCTION & DIMENTIONS
Inner conductor: Bare copper wire diameter 1,02mm +/-0,2
Insulation: Physically foamed PE diameter 4,6mm+/-01
Outer conductor (First Shield): Aluminium – no bounded foil Width 18mm tickeness 9n/12n/9n
Outer conductor (Second Shield): Tinned copper Braid 24x012 pitch 30mm 95%
Shield: Pet polyester foil width 18mm thickness 12 n
Jacket: White or Red
Option: LSZH version (mod. R1618HDTV-LSZH)
ELECTRIC CHARACTERISTIC
Characteristic impedance: 75 Ohm +/-3
Capacitance: 51,0 pF/mt +/-1
Velocity ratio: 16db
Tranfer impedance 5-30 MHz 85dB
1000-2000 MHz > 80dB
2000-3000 MHz > 75dB
Minimum setting Radius: 35mm
Total weight PVC type: 59,5 Kg/Km
Copper weight: 28,5 Kg/Km
I have been recently obsessed with magnetic loop antennas, and this is one element of such a radiator. I smoothed the aluminum out today. Just pieced together, but not set up to test capacitance. The diameter is 5" on the rotors. The shaft is 3/8" brass rod with stainless nuts. I chose the spacing of two nuts just randomly. I may have to reduce that and will certainly have to fine tune the spacing of the stator elements. The other brass rod is #10X32. The threads don't need to be fine--it takes too long to put on the nuts! The plexiglass was 3$ at AxMan Surplus here in St. Paul. The model is Oscar!
Reference® RIC01 instrument cable (LIVE ACT series)
Designed for LIVE applications, RIC01 instrument cable features outstanding wide and detailed frequency response, fast transients preservation, superior noise rejection, extreme flexibility, and greater mechanical stress relief. It is therefore recommended to all musicians who demand the ultimate in performance and reliability also for RUGGED STAGE and daily touring use. Unsurpassed TRANSPARENCY and clarity make this cable ideal for passive guitar pickups, allowing signal to be rich in dynamics and harmonics, and noise-free as well. Stranded inner core construction makes this cable more flexible, gives mechanical strength and avoids twisting, tangling and any shape-memory retention. Double braided copper shield and conductive sheath inside the screen provide strong protection against hum or noise caused by movement, besides making this cable sturdy and durable. Purest oxygen free copper conductor and low capacitance design provide higher pickup resonant peak and a brighter overall sound, preserving the unique personality of your tone. Hand assembled with highly reliable machined gold-plated plugs, RIC01 is your best guarantee for great-sounding live act.
Cable Specs
Inner Core: Stranded Red CU 42x015 Ø AWG18
Insulation: FOAM PE Ø 3,0 mm
Shield 1: PVC Semiconductor Ø 3,0 mm
Shield 2: Double Braided Red Copper
Jacket: Compound PVC Ø 7,6 mm
Bending Radius: 8x cable Ø
Impedance: 51 Ω
Capacitance cond/shield: 24 pF/ft
--------
Product Description
Warranty period: 5 years for meters guarantee replacement; 12 months for strips (non-human destruction)
Minimum quantity: 1, 000 glucose meters; 1000 bottles of strips
Volume of production: 5, 000 glucose metes and 30, 000 bottles of strips
Terms of payment: T/T 30% T/T depositing before production,
70% balance against copy of original B/L
Delivery times: 20 days after deposit (for MOQ only) (others according to quantity)
One kit of glucose testing system includes all the following
Biocare blood glucose meter
One adjustable lancet device
Owner's booklet
One carrying case
Two 3.0V lithium batteries (installed)
We offer you one sterile lancet free against each testing strip you buy
Specifications
Measuring Range: 2.2-27.8mml/L (40-500mg/dl)
Measuring Time: 20 seconds
Memory capacitance: 30
Power Source: Two replaceable 3-volt batteries (CR2032)
Batteries Life: > 1000 tests
Life of test strips: 12 months (vial sealed), 3 months (after vial opened)
Volume of blood: 3UL
Net weight: 52g
Dimensions: 97(L)*55(W)*15(H) mm
Features
All of our products are CE and ISO certificated with competitive price (NEGOTIABLE) and warranty in international market. Meanwhile, excellent services and prompt delivery help us win great fame among customers.
Website: www.sunmediking.com/
Product Specifiations:
Google Android 4.0 Operating System
Multi-Touch Capacitance Touch Screen + Dual Buttons Control
Processor: XBurst CPU > 1GHz
GPU: GC860
Memory: 512MB
Display Screen size: 7.0 inches HD LCD Monitor
800*480 screen resolution
Wifi 802.11b/g/n
3-axis G-sensor
Battery life: about 15wh
Battery capacity 4000mAh
Play time:
- Music: about 30 hours (wifi off, screen off and earphone working)
- Game function: about 6 hours
- Web: about 7 hours
- Video: about eight hours (wifi off and headphones working)
Language Support: Czech, Danish, Dutch, English, Spanish, French, German, Greek, Italian, Japanese, Korean, Norwegian, Polish, Portuguese, Russian, Swedish, Turkish, Chinese
Game function: Support (need to install third-party software)
Supported operating systems: Win2000/XP/VISTA/Windows 7
Extend Card: TF card, 2GB-4GB-8GB-16GB
buy this product from t.co/iEExXZrM
RPCM01/03 - Hi-Q Speaker Cable
RECOMMENDED FOR connecting all guitar and bass amplifier models made up of amp head and cabinet. This series was designed to maximize and provide the best signal transfer between the head and the speakers. For this application, we specifically designed two models, with different conductor section sizes, respectively 3,3 mm² and 5,22 mm², appropriate for different power heads (heads up to 50 and over 500 watt are available, connecting to a cabinet that can have two or up to eight loudspeakers). Generally speaker cables supplied for head and cabinet are generic cables; instead, for our power cables we adopted an “esoteric” multistrand setup for each conductor: 7 strands with red copper capillary twisted wires. A cable built in ‘multi-strand’ has a lower signal loss then a generic cable, moreover, we have created the two models with parallel conductors to provide lower capacitance. The cable sheath is in a transparent PVC Sunburst, which highlights the conductor threading. The increased 1/4 inch jack is necessary to support the different wattage of various amplifiers.
RPCM01 CONSTRUCTION SPECS:
Inner Conductor - Red Copper 2x(7x60x010) – 3,3 mm2 AWG12
Insulation - PVC transparent 1,5mm
Dimension - 4,3x9,50
Weight (Kg/100mt.) - 8,9Kg/100m
Power Rating - 23 Ampere
Available Color - transparent brown
Working Temperature - -20 +70°C
RPCM03 CONSTRUCTION SPECS:
Inner Conductor - Red Copper 2x(7x95x010) – 5,22 mm2 AWG12
Insulation - PVC transparent 1,5mm
Dimension - 5x10
Weight (Kg/100mt.) - 13Kg/100m
Power Rating - 31 Ampere
Available Color - transparent brown
Working Temperature - -20 +70°C
Hugo Morales Murguía
Composer based in the Hague.
Conductive guitar and electronics.
An exploration of capacitance and electricity using a guitar as an interface.
Wonderwerp #47
Wonderwerp series
Studio Loos, Den Haag 2013
boston, massachusetts
early 1970s
daymarc type 1620 sorter w/ teradyne test system
part of an archival project, featuring the photographs of nick dewolf
© the Nick DeWolf Foundation
Image-use requests are welcome via flickrmail or nickdewolfphotoarchive [at] gmail [dot] com
R1618HDTV video cables are used in critical digital and analog video connections and high quality applications (like HDTV/SDI ) in pre/post production facilities and network studios.
CONSTRUCTION & DIMENTIONS
Inner conductor: Bare copper wire diameter 1,02mm +/-0,2
Insulation: Physically foamed PE diameter 4,6mm+/-01
Outer conductor (First Shield): Aluminium – no bounded foil Width 18mm tickeness 9n/12n/9n
Outer conductor (Second Shield): Tinned copper Braid 24x012 pitch 30mm 95%
Shield: Pet polyester foil width 18mm thickness 12 n
Jacket: White or Red
Option: LSZH version (mod. R1618HDTV-LSZH)
ELECTRIC CHARACTERISTIC
Characteristic impedance: 75 Ohm +/-3
Capacitance: 51,0 pF/mt +/-1
Velocity ratio: 16db
Tranfer impedance 5-30 MHz 85dB
1000-2000 MHz > 80dB
2000-3000 MHz > 75dB
Minimum setting Radius: 35mm
Total weight PVC type: 59,5 Kg/Km
Copper weight: 28,5 Kg/Km
Prototype Biomedical Fluidic Antigen Van Der Pauw and/or Interdigital Capacitor Bio-Electronic Probe - USB Driven 16x16 Crosspoint Switch.
Provides high resolution differential capacitance, complex impedance and temperature.
Auto read when fixture lowered onto plate.
A circuit bending work station.
1. Resistance pots (4k7, 100k, 1m)
2. Capacitance - 12 caps selector
poly 47-pf, 100-pf, 470-pf, 1-nf, 4n7 nf, 10-nf, 100nf, 1-uf, 1uf
elec 1uf, 4.7uf, 10uf, 100uf
3. LED
4. Signal tracer simply a 1w amp maplin kit to trace audio signal in a circuit.
www.reidbrothers.co.uk/product-details/ridgid-meter-devic...
Email: uksales@reidbrothers.co.uk
Tele: 0141 425 1060
Ridgid Micro CM-100 Digital Clamp Meter Benefits:
The Ridgid micro CM-100 digital clamp meter is a meter for measuring the current of cables.
The Ridgid cable clamp meter has a very large capacity and measuring range.
Runs using a true RMS (Root Mean Square) and auto ranging unit.
The Ridgid micro CM-100 clamp meter can clamp around cables up to 30mm diameter.
The ability to measure current upto 1000A AC/DC.
CM-100 can be used as a multi meter for 8 other functions.
The Ridgid CM-100 digital clamp meter has an extra-large back lit LCD to allow the reading to be seen in poor lighting or small areas.
The Clamp meter can be passed through tight cable compartments as its slim and double moulded design makes the clamp ergonomically friendly.
The Ridgid micro CM-100 digital clamp meter comes in a soft carry case , along with test leads, a 9V battery and a type K temperature probe.
Ridgid Micro CM-100 Digital Clamp Meter Functions and Range:
Voltage AC/DC: 400.0mV - 600V
Current AC/DC: 400.0uA - 10A
Resistance: 400.0 - 400.0M
Capacitance: 4.00nF - 40mF
Frequency: Up to 4KHz
Diode Test: 1.5V
Continuity Test: 35
Temperature: -40oC - 1000oC
Ridgid Micro DM-100 Digital Multi-Meter Specifications:
Power Source: 9V Battery (included)
Display: 4000 Count Backlit LCD
Clamp Size: Max 30mm O.D Cable
Overload Protection: Cat. III 600V
Polarity Indication: Yes, Automatic
Auto Power Off: Yes, After 20 Minutes
AC/DC Current Range: 40A/400A/1000A
Auto Ranging: Yes
Manual Ranging: Yes (Single Button)
True RMS: Yes
Data & Peak Hold: Yes
Bargraph Display: Yes
Price: £99.00 (+VAT)
Doubler Capacitors replaced with a single capacitor for twice the capacitance. Doubler replaced with a 240V transformer.
What happens when you type? This spring depresses, altering the capacitance as seen by the pad underneath the spring!
The old paper - foil electrolytic (I think!!) type capacitor, which I re-used. I had thought it was a resistor; Uchi's helpful comment below suggested otherwise. Since then I've learned a little more about electronics and Uchi is correct. The readings (which I could not decipher before) indicated that this capacitor is rated for .08 micro (milli?) Farads, the "Farad" being the unit of capacitance. 160 VAC indicated that it will charge up to as many as 160 AC Volts before it discharges. "10-2065" is Sunbeam's in-house part number.
Don't ask me to accurately describe what "Capacitance" is and what these do, but, essentially a capacitor is like a rechargeable battery. It will accept an electrical charge up to a point, without allowing the charge to pass through. After a certain point it then discharges. In electric induction motors they are used for various purposes, including getting the motor started and timing the application of electrical charge to keep the motor running smoothly.
I think this is a paper foil type electrolyic capacitor; it ought to contain a rolled up thin metal (or other material) ribbon sandwiched in layers of paper, all saturated in a semi-liquid insulating medium similar to what you would find inside an alkaline battery. But I could be completely wrong about that.
Anyone want a bunch of Capacitance Electronic Discs? They are analog records with video encoded on them - pre-VHS home theater technology.
free, or best offer!
With Mundorf Supreme caps, F&T cap, Rikken Resistors and Blackgate caps.
i plan to replace the Auricaps to Mundorf MCap Supreme as well because i noticed that the auricaps are showing some leaks on the sides now due to age. I am also scouting for an audiophile grade power filter cap to replace the Nichicon, i cannot find an audiophile grade with the same values and capacitance.:(
Sign dielectric replaced with overhead projector transparency (OPT). OPTs are thinner, so the capacitance is higher than the same area using the plastic sign. At first, I used sections of aluminum about 1 and 1/2" wide for the peaker (the OPT serving as the dielectric). The laser did not work at all, so I used a smaller section of aluminum (lower capacitance by way of reduced area) and the device lased. Finally, I removed the aluminum sections entirely and replaced them with a single 1/2" aluminum "L" profile, after which I saw a big improvment in the output. This was all done using a Leyden Jar made from a "Smart Balance Buttery Spread" plastic container as the dumper. This video features the results obtained using the narrow, 1/2 "L" profile, from which the peaker became defined. In conclusion, it appears that reducing the capacitance of the peaker was required to enable lasing and tweak performance. The peaker therefore appears to determine the speed of the discharge through the laser channel, making the role of the dumper much less demanding, as is illustrated through the use of an actual Leyden Jar capacitor. Area of the base coupling, between the outside of the Leyden Jar and the common plate, appears to be relatively insignificant, as represented through the use of a single wire lead.
I have been recently obsessed with magnetic loop antennas, and this is one element of such a radiator. I smoothed the aluminum out today. Just pieced together, but not set up to test capacitance. The diameter is 5" on the rotors. The shaft is 3/8" brass rod with stainless nuts. I chose the spacing of two nuts just randomly. I may have to reduce that and will certainly have to fine tune the spacing of the stator elements. The other brass rod is #10X32. The threads don't need to be fine--it takes too long to put on the nuts! The plexiglass was 3$ at AxMan Surplus here in St. Paul. The model is Oscar!
The GI7B(T) can simply be clamped to the chassis but I went ahead and used a socket. I bought mine from VA3YP. The PVC flange that holds the chimney was cut from a plastic conduit fitting. Output circuit is a Pi-L. The plate choke is wound on a 3/8" piece of Delrin. The plate tuning cap was a Hammarlund I had in the junk box. I ended up with 3 stator and two rotor plates. Maximum capacitance is 10pF and minimum is 4pF. It is a bit less than half meshed when tuned for maximum output.
The trombone capacitor is useful for making magnetic loop antennas. It can (hopefuly) withstand the large voltages. The capacitance is adjusted, and the loop tuned, by sliding the inside in and out like a trombone. Two of these can be used in the loop.
It is quite long so also introduces inductance. I expect I'd run two shorter ones in parallel to make the whole thing quite compact so the properties of the loop are not too badly effected as it is tuned.
Here a 20mm plastic conduit fits tightly into a 22mm copper pipe. The 15mm copper pipe fits quite loosely up the middle.
Types
What kinds of Touch Panels Are You Looking for?
A touch panel is one of the kinds of computer display screens, which can also be called an input device. Due to the sensitivity to the pressure of the touch panel sensor, users interact with the computer by touching the objects on the screen.
Three types of touch screens are listed below:
Resistive Touch Screen:
A resistive touch screen panel is a sensor that is basically a film-plus-glass structure that converts the physical position of a touchpoint (X, Y) in a rectangular area into a voltage representing an X coordinate and a Y coordinate. Resistive touch screen panels are generally more affordable but provide only 75% clarity and the layer may be damaged by sharp objects. Resistive touch screens are immune to external elements such as dust or water.
Surface Wave Touch Screen:
Surface wave technology integrates acoustics, electronics, and semiconductors into new technology. They have the advantages of small size, flexible design, mature technology, good consistency, and reliability. Surface wave technology uses ultrasonic waves that pass over the touch screen panel. Surface wave touch screen panels are the most advanced one of the three types of screen touch panels, but they can be damaged by external elements.
Capacitive Touch Screen:
The resistive touch screen panel is constructed by placing a transparent thin-film conductor layer on the touch panel glass and adding a protective glass to the conductor layer. This double glass design completely protects the conductor layer and the inductor. With the rise of smartphones and tablets, the capacitive touch screen panel market has been developing rapidly.
Touch Points of the Touch Panel
Single, or Dual/Multi-Touch?
Single-touch interaction is capable of, at a lower price, realizing all the applications' goals. Gesture interaction, including, flick, slide and knead, requires dual/multiple support. Select the alternative to continue.
Single Touch Point Only
Aiming at supporting single-touch input, resistance touch screen is designed. Various types of materials are available because there is no limitation of the materials which are used for input. Besides, resistance touch screens have the advantages of mature technology, stability, high-cost competitiveness, and excellent detection accuracy.
The advantage of single-touch is that the device design space is optimized, especially for small devices, because it can "install" screens and buttons in the same area at the same time; second, because the buttons can be bound to any application in the operating system, So the "buttons" used by the device can reach an unlimited number.
Multiple Touch Point Support
The user's two hands have ten fingers, and when the users interact with each other, more fingers appear on the screen. This is the origin of the multi-touch concept of recognizing the position of a finger, which enables manipulation of more than two fingers. Projected capacitive touch screens support single or multiple touchpoints. It allows for the interaction of gestures. One point to mention is that no part of the resistive multi touch screen physically will move at detection, and it makes the touch experience smoother and lighter (just like smart-phone).
How Does Touch Panel work?
Different people work differently. So it is with different types of touch screens. Some can easily detect and distinguish multiple keys at the same time. However, some others can only sense one finger at a time. If you try to press two places at the same time on this type of screen touch panel, the screens will be rather confused. Here are some of the main technologies listed below:
Resistive Touch Panel
Resistive touch screen panel (the most popular technology recently) works a bit like "transparent keyboards" overlaid on top of the screen. The flexible upper layer of conductive polyester plastic is bonded to the rigid underlayer of conductive glass and separated by an insulating film. When you press the screen, you can force the polyester to touch the glass and complete the circuit - just like pressing a key on the keyboard. The chip inside the screen shows the coordinates of the location you touched.
When you press a resistive touch screen panel, you push two conducting layers together so they make contact, a bit like an ordinary computer keyboard.
Capacitive Touch Panel
The capacitive touch screen panel needs to achieve multi-touch, relying on the electrodes to increase the mutual capacitance. Simply put, the capacitive resistive touch screen is divided into blocks. Each set of mutual capacitance modules is working independently in each area, so the capacitive screen can be independent. Detecting the touch situation of each area, and after processing, simply implement multi-touch. When you bring your finger up to the screen, you alter the electrical field by a certain amount that varies according to where your hand is.
Touch Panel Solutions
We provide resistive and capacitive touch screen solutions to you.
In a capacitive touchscreen, the whole screen is like a capacitor. When you bring your finger up close, you affect the electric field that exists between the inner and outer glass.
Capacitive Touch Screen solutions
We offer a wide range of Projected Capacitive Touch Screen solutions to the market. There are four different PCAP construction options to choose from including Glass-Film-Film (GFF); Glass-Film (GF) and Double-Sided-ITO-Glass (GG2); Glass-Glass (GG); We are sure to have the perfect fit for your application's requirements.
Resistive Touch Screen Solutions
We offer a full range of 4-, 5- and 8-Wire Resistive Touch Screens that are available in Film-Glass (FG), Film-Film-Glass (PL) and Glass-Film-Glass (GFG) constructions. Our resistive touch screen solutions are a cost-effective, durable and versatile solution for many applications.
Hylozoic Soil is an interactive geo-textile mesh that senses human occupants and responds with air movement. Machine intelligence is embedded within networks of micro-controllers that coordinate arrays of capacitance and proximity sensors. Kinetic actuators are used to create a diffuse peristaltic pumping that pulls air and organic matter through the occupied space. The primitive cycles of opening, clamping, filtering and digesting in the artificial assembly are affected by some of the same natural forces that make a coral reef work. Building upon simple motions embedded within individual elements, accumulated actions produce turbulent wave-like reactions.
www.siggraph.org/s2009/galleries_experiences/biologic_art...
It's a noisy thing, like mini thunder. Getting about 6-8 inch long breakout on the top load. Approximately 3 million volts/meter to ionize the air to strike the arc (76,200 V/in). Another approximation is 75kV/in. Not bad for a first attempt. It's a fun and very rewarding weekend project, You learn a fair bit about electricity etc. It does require a lot of patience though. Building a Tesla coil is quite difficult. Here are my coil specs from JAVATC.
J A V A T C version 13.2 - CONSOLIDATED OUTPUT
1/24/2017, 10:43:39 AM
Units = Inches
Ambient Temp = 68ºF
----------------------------------------------------
Surrounding Inputs:
----------------------------------------------------
200 = Ground Plane Radius
200 = Wall Radius
200 = Ceiling Height
----------------------------------------------------
Secondary Coil Inputs:
----------------------------------------------------
Current Profile = G.PROFILE_LOADED
1.625 = Radius 1
1.625 = Radius 2
21.5 = Height 1
37.5 = Height 2
946.75 = Turns
26 = Wire Awg
----------------------------------------------------
Primary Coil Inputs:
----------------------------------------------------
Round Primary Conductor
3.75 = Radius 1
9.761 = Radius 2
23.25 = Height 1
23.25 = Height 2
10.4504 = Turns
0.25 = Wire Diameter
1 = Ribbon Width
0.1 = Ribbon Thickness
0.00419 = Primary Cap (uF)
30 = Total Lead Length
0.2 = Lead Diameter
----------------------------------------------------
Top Load Inputs:
----------------------------------------------------
Toroid #1: minor=3.5, major=8, height=42.5, topload
----------------------------------------------------
Secondary Outputs:
----------------------------------------------------
381.64 kHz = Secondary Resonant Frequency
90 deg ° = Angle of Secondary
16 inch = Length of Winding
59.2 inch = Turns Per Unit
0.00096 inch = Space Between Turns (edge to edge)
805.5 ft = Length of Wire
4.92:1 = H/D Aspect Ratio
32.6094 Ohms = DC Resistance
29718 Ohms = Reactance at Resonance
0.62 lbs = Weight of Wire
12.393 mH = Les-Effective Series Inductance
13.794 mH = Lee-Equivalent Energy Inductance
13.678 mH = Ldc-Low Frequency Inductance
14.033 pF = Ces-Effective Shunt Capacitance
12.608 pF = Cee-Equivalent Energy Capacitance
22.752 pF = Cdc-Low Frequency Capacitance
4.61 mils = Skin Depth
8.308 pF = Topload Effective Capacitance
119.5989 Ohms = Effective AC Resistance
248 = Q
----------------------------------------------------
Primary Outputs:
----------------------------------------------------
381.64 kHz = Primary Resonant Frequency
0 % = Percent Detuned
0 deg ° = Angle of Primary
36.96 ft = Length of Wire
6.13 mOhms = DC Resistance
0.325 inch = Average spacing between turns (edge to edge)
1.992 inch = Proximity between coils
2.53 inch = Recommended minimum proximity between coils
40.804 µH = Ldc-Low Frequency Inductance
0.20197 µF = Cap size needed with Primary L (reference)
0.861 µH = Lead Length Inductance
96.188 µH = Lm-Mutual Inductance
0.129 k = Coupling Coefficient
0.127 k = Recommended Coupling Coefficient
7.75 = Number of half cycles for energy transfer at K
10.05 µs = Time for total energy transfer (ideal quench time)
----------------------------------------------------
Transformer Inputs:
----------------------------------------------------
20 [volts] = Transformer Rated Input Voltage
25000 [volts] = Transformer Rated Output Voltage
2000 [mA] = Transformer Rated Output Current
60 [Hz] = Mains Frequency
20 [volts] = Transformer Applied Voltage
0 [amps] = Transformer Ballast Current
----------------------------------------------------
Transformer Outputs:
----------------------------------------------------
50000 [volt*amps] = Rated Transformer VA
12500 [ohms] = Transformer Impedence
25000 [rms volts] = Effective Output Voltage
2500 [rms amps] = Effective Transformer Primary Current
2 [rms amps] = Effective Transformer Secondary Current
50000 [volt*amps] = Effective Input VA
0.2122 [ºF] = Resonant Cap Size
0.3183 [ºF] = Static gap LTR Cap Size
0.5533 [ºF] = SRSG LTR Cap Size
331573 [ºF] = Power Factor Cap Size
35355 [peak volts] = Voltage Across Cap
88388 [peak volts] = Recommended Cap Voltage Rating
2.62 [joules] = Primary Cap Energy
359 [peak amps] = Primary Instantaneous Current
323.1 [inch] = Spark Length (JF equation using Resonance Research Corp. factors)
20.7 [peak amps] = Sec Base Current
----------------------------------------------------
Rotary Spark Gap Inputs:
----------------------------------------------------
1 = Number of Stationary Gaps
4 = Number of Rotating Electrodes
1800 [rpm] = Disc RPM
0.375 = Rotating Electrode Diameter
0.375 = Stationary Electrode Diameter
10.6 = Rotating Path Diameter
----------------------------------------------------
Rotary Spark Gap Outputs:
----------------------------------------------------
4 = Presentations Per Revolution
120 [BPS] = Breaks Per Second
56.8 [mph] = Rotational Speed
8.33 [ms] = RSG Firing Rate
0.262 [ms] = Time for Capacitor to Fully Charge
5 = Time Constant at Gap Conduction
750.73 [us] = Electrode Mechanical Dwell Time
100 [%] = Percent Cp Charged When Gap Fires
35355 [peak volts] = Effective Cap Voltage
2.62 [joules] = Effective Cap Energy
644518 [peak volts] = Terminal Voltage
314 [power] = Energy Across Gap
238.5 [inch] = RSG Spark Length (using energy equation)
----------------------------------------------------
Static Spark Gap Inputs:
----------------------------------------------------
2 = Number of Electrodes
1.5 [inch] = Electrode Diameter
0.25 [inch] = Total Gap Spacing
----------------------------------------------------
Static Spark Gap Outputs:
----------------------------------------------------
0.25 [inch] = Gap Spacing Between Each Electrode
35355 [peak volts] = Charging Voltage
19830 [peak volts] = Arc Voltage
34822 [volts] = Voltage Gradient at Electrode
79320 [volts/inch] = Arc Voltage per unit
56.1 [%] = Percent Cp Charged When Gap Fires
0.049 [ms] = Time To Arc Voltage
20425 [BPS] = Breaks Per Second
0.82 [joules] = Effective Cap Energy
361497 [peak volts] = Terminal Voltage
16826 [power] = Energy Across Gap
332.9 [inch] = Static Gap Spark Length (using energy equation)
One of my newly acquired power converter boards didn't want to work. A closer look revealed the reason - Mr postman has been playing football with my package, and the inductor is rather beaten up.
Close inspection showed another board had similar, but less serious damage, and was still working. This one however is dead.
Oh well, could be worse. Only a 25p component, I'll change it over.
Only tricky bit is it is only 2.5mm wide - see, it is a macro! Best I lay off the caffeine before I do this one!
The board is an AA power board from Jeelabs.
This clever little board mounts a single AA or AAA battery (rechargeable if you like) and converts the 1.2v or 1.5v into 3.3v to power the JeeNode boards I use for my flash triggers (amongst other things). I've got a few code changes to make which will improve the power consumption of my remote flash triggers, but even now, thanks to this board, a single 2400mAh NiMH rechargeable battery can run a remote unit for 20 hours solid. Far longer than both I or my camera battery can last! Plus as this DC power converter board will produce 3.3v from input voltage as low as 0.8v I can even run it on batteries that are "flat" as far as the flashes are concerned.
I guess I should have a look at mounted a solar panel and NiMH charging circuit in the box and then the remotes will recharge just by putting them on the window ledge!
The title? Well inductors are measured in Henry's after an American Scientist Joseph Henry who discovered electromagnetic induction at about the same time as Michael Faraday. Faraday had already given his name to capacitance, so Henry managed to avoid an argument on this unit!
en.wikipedia.org/wiki/Henry_%28unit%29
--- Shot information ---
Shot in manual mode with a 50mm f/1.8D stopped to f/11 mounted on the front of the full set of DIY modified cheap Chinese extension rings.
www.flickr.com/photos/steve_snaps/3834843015
Lighting via SB800 in TTL mode triggered by CLS. Flash is about 5m above the board slightly to the right pointing down at 45 degrees. The SB800 has a built in catch light bounce card, which I deployed, this acts a great reflector on a target this small and throws some light from the left hand side.
We’ve been using Ciphone C4 for a couple months now, and our first impressions mainly consisted of “CiPhone C4 Capacitive Touchscreen makes Windows Mobile a gazillion times better to use”. But how can you figure out what the difference between Capacitive and Resistive Touch screens really are?
For the professional technical details, please read the Wikipedia articles on Resistiveand Capacitive technology.
Cell Phones and other personal electronics devices such as tablet PCs are sometimes equipped with touch screens, while in the cell phone industry there are two major categories of touchscreen displays: capacitive touchscreens and resistive touchscreens.
What is capacitive and resistive touchscreen?
Capacitive touchscreen displays rely on the electrical properties of the human body to detect when and where on a display the user touching. Because of this, capacitive displays can be controlled with very light touches of a finger and generally cannot be used with a mechanical stylus or a gloved hand. Examples of devices with capacitive touchscreen are the Ciphone C4and Ciphone 4 A3 Android.
Resistive touchscreen displays are composed of multiple layers that are separated by thin spaces. Pressure applied to the surface of the display by a finger or stylus causes the layers to touch, which completes electrical circuits and tells the device where the user is touching. As such, resistive type touchscreens require much more pressure to activate than capacitive touchscreen. Examples of devices with resistive touchscreens are the A4 Touchscreen GPS Phone and 4G+++ WiFi Phone.
What’s the difference between Capacitive and Resistive?
A capacitive touchscreen measures the interaction between an electrical signal on a transparent grid above the screen and the user’s finger. A capacitive screen is beautifully smooth to operate because it just requires the presence of your finger, not any pressure. The flip side of this is that you can’t use a stylus. Well, actually there is a kind of chunky stylus that mimics the capacitance of a human finger, but it’s not elegant to use.
While a resistive touchscreen has two thin layers of conductive but transparent film above the screen, and measures the change in resistance between the two layers due to the pressure of touch. Resistive touchscreens are cheaper to make, but don’t support multi-touch. If the user presses with more than one finger the device can’t determine the position of the multiple fingers. Multi-touch for resistive displays has been demonstrated in the lab, but is not currently practical for consumer devices. A resistive screen can be made pressure-sensitive, so that applications may distinguish between a light and a heavy touch. A capacitive screen just knows “finger present” and “finger absent”.
To be quite honest, the only positive I’ve heard about resistive touchscreens, is that it is a screen tech which works with gloved hands and a stylus. But personally, I’ve found that using even a resistive screen with outdoor winter gloved hands is just about impossible. I feel capacitive is a lot more responsive on average and I quite prefer how the screen needs to only be touched, not pressed. I also like that Capacitive touchscreen which is much more durable and scratch-resistant. So what’s your opinion? Leave your comment and share with us.
THEREMIN: strumento elettronico / dal sito di Mr. Popescu www.benedict-popescu.ro
Question 1: Is this instrument your invention ?
Answer 1: It is quite an old idea, belonging to the Russian Lev Sergeivitch Termen (Anglicised to Leon Theremin). He invented the instrument immediately after the first world war (in 1919 actually) while a student at the University of Petrograd. At that time electronics was still very close to its beginnings. Theremin’s invention was, in fact, the first synthesis of an acoustic sound using electronic circuits. That’s why Leon Theremin is now recognised as being the parent of other electronic musical instruments (analog and digital synthesisers). As you probably realise, the instrument is not my invention, but it is 100% my own design (see the explanations concerning my style of play – the Answer to Question 10).
Question 2: What is the name of this instrument ?
Answer 2: It is called theremin, coming from the name of its inventor. The instrument was initially called the ‘aetherphone’, then the ‘thereminvox’ and finally it received the name of its inventor.
Question 3: How does it work ?
Answer 3: The theremin is based on the ‘beat frequency oscillator principle’ or heterodyne effect. The audio signal arises from the difference between relatively high frequencies of two oscillators - one having a fixed frequency and the other one a variable frequency. The variation of the oscillation frequency for the second oscillator is determined by the variation in capacitance of only a few picofarads between an antenna and the player’s hand. Two such pairs of oscillators are used in each theremin: one is to control the pitch and the other one is to control the volume. The player uses his (or her) hands to control simultaneously the pitch and the volume.
Question 4: Is the theremin sensitive to any body or hands movements around it ?
Answer 4: Yes. The theremin ‘feels’ the presence of any body, hands or even fingers (not only of the player, but of any other person or animal!) moving in its proximity.
Question 5: Is it difficult to play the theremin ?
Answer 5: Yes. The theremin is, in my opinion, the most difficult instrument to play. One difficulty comes from the fact that the performers have to move their hands in real time (sometimes with the precision of a millimetre or even less), the only control being the results of these movements. Another difficulty comes from the fact that, when the performer has to play higher and higher notes, the ‘spacing’ (or distance between hand positions in space corresponding to successive notes) becomes smaller and smaller, thus making the intonation of achieved notes less and less accurate.
Question 6: Does the player touch the theremin while performing ?
Answer 6: No, not at all. The player only touches the knobs for tuning the instrument before performance, but not during playing. The theremin is unique in that it is played without there being any physical contact whatsoever between the performer and the instrument. Therefore the theremin performer plays without the benefit of any tactile reference. Unlike, say, a violinist, who is in continuous contact with the instrument’s fingerboard, the thereminist feels no shape or force when moving from one pitch (or volume) to another. The performer is constantly moving his or her hands, listening carefully to how the resulting sound changes, and then intuitively ‘trimming’ the precise position of the hands to get the desired pitch and volume. The process is one of continuous feedback. Notably playing the theremin can produce music of great expressiveness. The player leaves his personal mark on the rendition.
Question 7: Does everyone have chances to become a good thereminist ?
Answer 7: Unfortunately not. There is a minimum of conditions without which it does not merit to try: you must have a perfect ear for music and a very precise control of hand motions.
Question 8: Anything else?
Answer 8: Yes. Practice, practice and again practice until you will be able to move in real time your hands for faster and faster melodies in order to play them with correct intonation. Even more practice (years and years) will be required until you can play with feeling (to be capable of transmitting a sentiment from your heart to the heart of those in your audience).
Question 9: Are there different styles in playing the theremin ?
Answer 9: Yes. First of all, as for any other instrument, there are right and left handed players. But not only this. Most people play the theremin in the 'classical' style. For the classical theremin the pitch antenna is placed vertically in the right hand corner of a wooden or otherwise non-conducting cabinet. The volume antenna, usually shaped as a loop, is normally placed horizontally on the left hand side of the cabinet. The player changes the pitch of the sound by moving the right hand in a horizontal plane near the pitch antenna. The closer the hand is to the antenna, the higher the pitch of the generated sound. The player controls the loudness of the sound by moving the left hand in a vertical plane near the volume antenna. When the hand is close to the antenna the instrument is silent and maximum volume is obtained when the hand is moved away from the antenna. As you will see below, in playing the theremin I use my skills as a musical saw player and I have my own style, which I believe is unique in the world.
Question 10: Is it important how you place in space the pitch and the volume antennae ?
Answer 10: No. In order to avoid the interference between the two antennae you must place them in perpendicular planes. What is different in my style of play is the fact that I have changed the configuration in space for the pitch and volume antennae in comparison with the 'classical' style. For my theremin I use two pitch antennae, placed in horizontal planes, of the same length but different thicknesses. This arrangement allows me to improve the ‘spacing’. In order to control the pitch I can play low notes by bringing my left hand from my body nearer to the lower antenna, and higher and higher notes by moving my hand from the low to the high antenna. The way of controlling the volume is inverted when compared with the ‘classical’ style. The volume antenna looks like a simple plate - placed in the vertical plane. When my right hand is away from the plate the theremin is silent and the volume increases to the maximum when my right hand is moved closer, to within two inches of the plate.
Question 11: What about the tone produced by the theremin ?
Answer 11: The tone of the theremin depends on the instrument model used. Some people prefer the tone of theremin made by RCA (Radio Corporation of America) in the nineteen-thirties using electronic tubes. The tone of this model is close to that of a violin. Some other people like rather a smooth ethereal tone. I personally prefer the second one which is likened to that of a musical saw.
Question 12: Is it possible to use the theremin to create sounds other than that of the theremin itself ?
Answer 12: Yes. You can interface your theremin with other (digital) sources of sounds (sound modules, samplers, computers, etc.) using a MIDI (Musical Instrument Digital Interface) and command with your theremin these devices to generate sounds of a large timbral variety. The only requirement is to own a fast and accurate enough MIDI device.
Harbor Freight 37772 AC/DC Digital Multimeter.
~ Get accurate readings for AC/DC voltage, AC/DC current, diode overload protection, and audible continuity.
~ Features an easy-to-read LCD display
~ Date hold button retains information
~ Display capacity of 1999
~ Capacity: DC voltage: 2-20-200-1000V
~ AC voltage: 2-20-200-700V
~ DC current: 2mA-20mA-200mA-20A
~ AC current: 20-200M
~ Hz range: 20K
~ Capacitance range: 2N-20N-200N-2V-20V
~ Temperature probe: 20 Celsius to 1000 Celsius
Drilling S.S.E.
Top Panel
Chassis to cabinet holes 5/8” from ends of metal. Use 13/64” drill bit to finish but start with a 3/32” pilot hole for safety.
On-Off Switch 1&1/2” measured from the left side. Start with a smaller pilot holes until you can use a small stepped Versa Bit to get to finished hole size of approximately .493”.
Fuse Assembly 2&1/2” measured from the left side. Same size as On-Off switch.
Pilot Light 3&1/2” measured from the left side. I used a real Fender assembly so a .684” (11/16”) was made with pilots and Versa Bit.
Cathode Bypass switch 5&1/4 measured from the left side. Use a 1/4” bit to finish but start with smaller pilot holes.
Tone Pot 6&1/2” measured from the left side. 3/8” hole.
Volume Pot 7&3/4” measured from the left side. 3/8” hole.
Deep/Bright Switch 10” measured from the left side. 1/4” hole.
Input Jack 11&1/4” measured from the left side. 3/8” hole.
Hole For Power Transformer
Mark the center line of the 7” deep chassis at 3&1/2” .
Make sure that you locate the power transformer on the opposite side from the input jack!
Mark a line 1/2” from the edge of the chassis.
Take the end bell off and use it as a marking and drilling guide. Easy!
Position the short end of the end bell on the 1/2” line.
Mark the four mounting holes and also trace around the edge of the entire end bell.
The raised portion of the bell is 1/2” from the flat portion with the mounting holes.
So, you’ll need to cut out a rectangle slightly larger than that so it will fit smoothly through the hole, right?
Draw your cutting lines accordingly.
Now drill a 1/8” hole just inside each corner of your drawn rectangle.
Drill a 1/8” also in the center of the drawn rectangle and also four more 1/8” holes about an inch away from each of your corner holes. Now enlarge all but the four corner holes up to 3/8” gradually! These are you access holes for your fine tooth cutting saber saw blade. Start cutting metal from access hole to access hole. Once you’ve removed some metal you can start cutting along your straight lines very carefully. Remember, the straighter your cuts the less filing you’ll need to do later to straighten up the rectangular cut. Finish up with 100 grit abrasive paper so there’s no chance of a sharp edge cutting any of your wires or fingers!
I ended up with a rectangular hole cutout that measured 2.842” X 2.169”. The end bell now fits very nicely.
Now drill the four 3/16” screw mounting holes.
Reassemble the power transformer and check for fit.
Mount Output Transformer.
Mark a line along the long side 2” from the edge where the sockets will be mounted. The first hole will be located 3&1/4” from the side of the chassis opposite the power transformer. The second hole will be around 7&1/4” in from the edge. Actually, when you drill the first hole you can just plop down the 125ESE and you’ll know where the second hole should be drilled. I used an 11/64” bit.
Mount Choke.
I ‘eyeballed” this mount. I wanted to get it close to the rectifier tubes but not bump into the power transformer.
Mount Board On Standoffs
Mark a line 3/4” from the edge of the chassis opposite from the power transformer side. This is the 7” deep portion of the chassis. The first of the four holes you’ll need to drill to mount the board on its standoffs will be 2” in from the side of the chassis where the sockets will be mounted, dig? Mark a line 2” in from that long edge; this is where you’ll drill the second of the four holes. Once you have those two holes drilled use a couple of drill bits or metal rods to hold the board in base so you can use it as a drilling jig to mark the location of the last two hole. I used a 9/64” bit and that works out really nice with the 6-32 machine screws I use to hold the board in place. If you buy the orange board like I’m using here you’ll need to open up the four mounting holes as well with the 9/64” bit.
Drilling The Tube Socket And AC Cord Holes
Draw a center line on the tube socket side of the chassis box. It’s 2” deep so 1” in is the center. Measure 3/4” in from the side where power transformer goes and that’s where you drill out box for the AC cord with push-in strain relief. For the first tube socket measure 2& 3/8” from the side where the power transformer goes. The other sockets are all 2” apart so also mark the line at 4&3/8”, 6&3/8”, 8&3/8” and 10&3/8”. Center punch each hole ant then drill a 3/32” pilot hole. Keep opening up the holes with progressively larger bits until the #4 Unibit fits through. When you get to the hole for the 12AX7A socket be very careful not to open it up too much. Check your work as you go. The socket I chose fit a .749” (almost 3/4”) hole very nicely. With the Unitbit spinning we’re talking Torque City so put the chassis down flat on your padded bench top and drill from the side. Hold down the chassis with the palm of your hand or clamp it carefully with blocks of wood. When I tried to finish the holes with the larger Unibit I found that I needed a drill with a 1/2” chuck that I no longer owned! It was Christmas Eve but I found an open ACE Hardware and bought one. The battery in the box was uncharged so I went home and stole one from my Craftsman mower! The final octal socket holes are about 1” diameter. I eyeballed the screw holes and punched ‘em with the General. Finish drilling size for the mounting holes is 1/8”. I’m using 4-40 machine screws and kep nuts to keep them in place. Thats a vintage HEYCO 7P-2 strain relief same as I used on the OG SSE. Hole size here is 3/4”. If you work carefully the sockets should fit into the holes very smoothly with no binding or other hassles. I used hemostats to hold the little kep nuts in place while I spun the machine screws. I'll replace the cad plated screws with stainless steel I just ordered from Graingers. The octal tube sockets are Made At China. No, they're not as classy as the Azuma sockets I used in the OG but they're battle tested in a zillion modern Fender and other amps. The 9 pin socket is a pretty nice modern China copy of the Japan Azuma.
As this project progresses I realize that I'm trying to make everything I possibly can as close to the OG as possible. When I mounted the board I realized that the OG standoffs were shorter so I going to change those out. It's possible that there would be a change in capacitance with the board positioned higher or lower.
VCCINT is the FPGA's 1V power rail for internal logic. The board stackup is 6 layers with 2 ground, 2 signal, 1 power, and 1 power/signal mixed layer. I routed the VCCINT supply to the FPGA on that layer and wasn't able to get as much of a connection as I would have liked to.
I figured, no problem, only bulk capacitance is required for this rail, the rest of the decoupling is on package, so what if there is some extra inductance. Unfortunately, my sad VCCINT plane was amounting to a resistance from the PMU measurement point (a bulk decoupling cap) to the actual VCCINT solder balls of 8 milliohms.
8 milliohms may not sound like a lot, but the board has 40A capacity for the 1V VCCINT rail. 40 * 0.008 = 0.240V, yikes! I was able to run a sense pair from the back side of the board, back around to the PMU, fixing the issue (mostly, I still need to add a decoupling cap to the measurement point).
However, this fix reveals another problem, while my FPGA has a proper cooling solution, my power modules do not. Even at around 70% capacity, the modules start to overheat. I need to find either a way to attach a heatsink to the very small components, or just setup some kind of ghetto forced air solution.
Unloaded secondary waveform. Buffer capacitance is much higher than necessary in this situation, but all of it is required when low power factor loads are plugged in.
Straighwire Symphony II, DIY interconnect semi-balance cable assembly with Wireworld RCAs.
2 inner wires (red+white) connected to center pin of RCA, other 2 inner wires (black+grey) 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 for 0.5 meters
There's no amplifier circuit yet--the audio lines are soldered directly onto a 3.5mm stereo socket. And the aerial is connected to a wire soldered with a dodgy SMA pin on one end and direct to the module board on the other. And I was losing bytes every four packets or so, and I don't really know anything about transistors but I guessed the input capacitance might be affecting their switching speed and so swapped them out for some quicker ones and that fixed it.
But it works, it works! I'm issuing commands in a Python shell, so my packet interpreter and constructer works fine. And I can browse the service list, get the unique identifiers, and tune into stations. And, surprise of surprises, actual radio actually comes actually out of the actual bloody headphones.