All Clarification Of Electronic

Electron multipliers And Vacuum tubes in the 21st century

epuel.saepuloh@gmail.com (epuel) — Sat, 12 Nov 2011 06:57:00 -0800

The highest possible vacuum is desired in a tube. Remaining gas atoms will ionize and conduct electricity between the elements in an undesired manner. In a defective tube residual air pressure will lead to ionization, becoming visible as a pink-purple glow discharge between the tube elements.
To prevent gases from compromising the tube's vacuum, modern tubes are constructed with "getters", which are usually small, circular troughs filled with metals that oxidize quickly, barium being the most common. While the tube envelope is being evacuated, the internal parts except the getter are heated by RF induction heating to

Getter in opened tube; silvery deposit from getter

help free any remaining gases from the metal parts. The tube is then sealed and the getter is heated to a high temperature, again by radio frequency induction heating. This causes some material from the getter to

Tube tester manufactured in 193evaporate, reacting with any residual gases and usually leaving a silver-colored metallic deposit on the inside

Voltage regulator tube in operation. Low pressure gas within tube glows due to current flow.

of the envelope of the tube. The getter continues to absorb small amounts of gas that may leak into the tube

70 watt tube audio amplifier selling for $2,680^[23] in 2011, about 10 times the price of a comparable model using transistors.[24during its working life. If a tube develops a serious leak in the envelope, this deposit turns a white color as it reacts with atmospheric oxygen. Large transmitting and specialized tubes often use more exotic getter materials, such as zirconium. Early gettered tubes used phosphorus based getters and these tubes are easily identifiable, as the phosphorus leaves a characteristic orange or rainbow deposit on the glass. The use of phosphorus was short-lived and was quickly replaced by the superior barium getters. Unlike the barium getters, the phosphorus did not absorb any further gases once it had fired.

Heat generation and transfer Power

epuel.saepuloh@gmail.com (epuel) — Sat, 12 Nov 2011 06:50:00 -0800

A considerable amount of heat is produced when tubes operate, both from the filament (heater) but also from the stream of electrons bombarding the plate. The requirements for heat removal can significantly change the appearance of high-power vacuum tubes. Although the miniature tube style became predominant in consumer

The anode (plate) of this transmitting triode has been designed to dissipate up to 500W of heat

equipment, high power audio amplifiers and rectifiers would still require the larger "octal" style of enclosure. Transmitting tubes could be much larger still.
Most tubes produce heat from two sources during operation. The first source is the filament or heater. Some tubes contain a directly heated cathode. This is a filament similar to an incandescent electric lamp; some types glow brightly like a lamp, but most glow a dim orange-red. The "bright emitter" types possess a tungsten filament alloyed with 1–3 % thorium which reduces the work function of the metal, giving it the ability to emit sufficient electrons at about 2000 degrees Celsius. The "dull emitter" types also possess a tungsten filament but it is coated in a mixture of calcium, strontium and barium oxides, which emit electrons easily at much lower temperatures due to a monolayer of mixed alkali earth metals coating the tungsten; these only reach 800–1000 degrees Celsius.
The second form of cathode is the indirectly heated form which usually consists of a nickel cylinder, coated on the outside with the same strontium, calcium, barium oxide mix used in the "dull emitter" directly heated types. Inside the cylinder is a tungsten filament to heat it. This filament is usually uncoiled and coated in a layer of alumina (aluminium oxide) in order to insulate it electrically from the actual cathode. This form of construction allows for a much greater electron emitting area and allows the cathode to be held at a potential difference, typically 150 volts more positive than the heater or 50 volts more negative than the heater. For small-signal tubes such as used in radio receivers, heaters consume between 50 mW and 5 watts, (directly heated), or between 500 mW and 8 watts for indirectly heated types. Thus even a small signal amplifier might consume a watt of power just to warm its heater, compared to the milliwatts (or less) that a modern semiconductor amplifier would require for the same function. Even in power amplifiers the filament power may be responsible for an appreciable reduction in efficiency.
The second source of heat is generated at the plate (anode), as electrons accelerated by its high voltage strike it, depositing their kinetic energy there and raising its temperature. In tubes used in power amplifiers or transmitter output stages, this source of heat will far exceed the power due to the cathode heater. The plates of improperly operated or overloaded beam power tubes can sometimes become visibly red hot; this should never occur under normal operation of consumer electronics and is a precursor to tube failure.
Heat escapes the device by black body radiation from the anode (plate) as infrared radiation. Convection is not possible in most tubes since the anode is surrounded by vacuum. Considerations of heat removal can affect the overall appearance of some tubes. The anode is often treated to make its surface less shiny and darker in the infrared (see black body radiator). The screen grid may also generate considerable heat, which is radiated toward the plate which must reradiate that additional heat along with the heat it generates itself. Limits to screen grid dissipation, in addition to plate dissipation, are listed for power devices. If these are exceeded then tube failure is likely.
Tubes used as power amplifier stages for radio transmitters may have additional heat exchangers, cooling fans, radiator fins, or other measures to improve heat transfer at the anode (plate). High power transmitting tubes may have the surface of their anodes external to the tube, allowing for water cooling or evaporative cooling. Such a water cooling system must be electrically isolated to withstand the high voltage present on the anode.
Tubes which generate rather little heat, such as the 1.4 volt filament directly heated tubes designed for use in battery powered equipment, often have shiny metal anodes. 1T4, 1R5 and 1A7 are examples. Gas filled tubes such as thyratrons may also use a shiny metal anode since the gas present inside the tube allows for convection of heat from the anode to the glass enclosure.
The outer electrode in most tubes is the anode (plate). Some small signal types, such as sharp and remote cut-off R.F. and A.F. pentodes and some pentagrid converters have a shield fitted around all the electrodes enclosing the anode. This shield is sometimes a solid metal sheet, treated to make it dull and gray so that it can itself reradiate heat generated from within. Sometimes it is fabricated from expanded metal mesh, acting as a Faraday cage but allowing sufficient infrared radiation from the anode to escape. Types 6BX6/EF80 and 6BK8/EF86 are typical examples of this shielded type using expanded mesh. Types 6AU6/EF94 and 6BE6/EK90 are examples which use a gray sheet metal cylindrical shield.

Tube packages High Power

epuel.saepuloh@gmail.com (epuel) — Sat, 12 Nov 2011 06:43:00 -0800

Most modern tubes have glass envelopes, but metal, fused quartz (silica), and ceramic have also been used.

High power GS-9B triode transmitting tube with heat sink at bottom.

The first version of the 6L6 used a metal envelope sealed with glass beads, while a glass disk fused to the

Metal cased tubes with "octal" bases

metal was used in later versions. Metal and ceramic are used almost exclusively for power tubes above 2 kW dissipation. The nuvistor was a modern receiving tube using a very small metal and ceramic package.
Tubes have always had their internal elements connected to external circuitry using pins at their base which plug into a socket. After all, tubes needed to be replaced rather frequently unlike modern semiconductor devices which are mostly soldered in place. Subminiature tubes were produced using wire leads rather than sockets, however these were restricted to rather specialized applications. In addition to the connections at the base of the tube, many early triodes connected the grid using a metal cap at the top of the tube; this was done in order to reduce stray capacitance between the grid and the plate leads. Tube caps were also used for the plate (anode) connection, particularly in transmitting tubes and tubes using a very high plate voltage.
High power tubes such as transmitting tubes have packages designed more to enhance heat transfer. In some tubes, the metal envelope is also the anode. The 4CX1000A is an external anode tube of this sort. Air is blown through an array of fins attached to the anode, thus cooling it. Power tubes using this cooling scheme are available up to 150 kW dissipation. Above that level, water or water-vapor cooling are used. The highest-power tube currently available is the Eimac 4CM2500KG, a forced water-cooled power tetrode capable of dissipating 2.5 megawatts. (By comparison, the largest power transistor can only dissipate about 1 kilowatt.)

Electron Tube Thermionic Valve

epuel.saepuloh@gmail.com (epuel) — Sat, 12 Nov 2011 06:31:00 -0800

Vacuum tubes with two active elements ("diodes") are used for rectification. Ones with 3 or more elements ("triodes", "tetrodes", etc.) are used for amplification, functions which rely on amplification such as oscillators,

Modern vacuum tubes, mostly miniature style

In electronics, a vacuum and switching.
Standard tubes with cathode, grids, and anode are classified in various ways according to requirements. They

Early RCA triode vacuum tube, type 808

may be classified by frequency range (audio, radio, vhf, uhf, microwave), power rating (small-signal, audio power, high-power radio transmitting), design purpose (sharp versus remote cutoff; amplifying and switching, control and signal amplification, rectification, mixing, general-purpose versus very low microphonic and low noise audio amplification, and so on). Distinctions are not necessarily sharp; for example similar dual triodes can be used for audio preamplification and as flip-flops in computers, although linearity is important in the

Triodes as they evolved over 40 years of tube manufacture, from the RE16 in 1918former case and long life in the latter.
Other tubes which could be called vacuum tubes have different construction and different functions, such as cathode ray tubes which create a beam of electrons for display purposes (such as the television picture tube)

Vacuum tube with plate (anode) cut open revealing grid.

in addition to more specialized functions such as electron microscopy and electron beam lithography. X-ray tubes are also vacuum tubes. Phototubes and photomultipliers also rely on electron flow through a vacuum, though in this case the emission of electrons from the cathode depends on energy from photons rather than thermionic emission. Since these sorts of "vacuum tubes" have functions other than electronic amplification and rectification they are described in their own articles.

Ramsey FM10C FM Stereo Transmitter Kit

epuel.saepuloh@gmail.com (epuel) — Sat, 25 Jun 2011 02:03:00 -0700

Ramsey FM10C FM Stereo Transmitter Kit

by Ramsey

4.0 out of 5 stars See all reviews (4 customer reviews) | Like (0)

Price:	$44.95
	o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o o

In stock.
Processing takes an additional 2 to 3 days for orders from this seller.
Ships from and sold by Ramsey Electronics®.

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Technical Details

Have your own stereo FM station for less than $50!
Tunable anywhere in standard FM band... 88 to 108 MHz
Standard line level inputs with RCA phono jacks
Setable pre-emphasis 50 or 75 µSec for use anywhere in the world
Electronic kit, assembly required

Product Details

Item Weight: 4 ounces
Shipping Weight: 1.5 pounds (View shipping rates and policies)
ASIN: B0002NRIMS

Average Customer Review: 4.0 out of 5 stars See all reviews (4 customer reviews)

Amazon Bestsellers Rank: #68,783 in Electronics (See Top 100 in Electronics)
Date first available at Amazon.com: July 21, 2004

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Product Description

That's right, we said STEREO! Just connect a cassette deck, CD player or mixer panel to the FM10C's line level inputs and you're on-the-air with a school, dorm, camp, home, church or neighborhood FM station! Here's a great entry-level kit that will teach the basics of FM Broadcast Transmission while finding many uses around the home or dorm room. The FM10C has plenty of power to cover your home, back yard, or city block. Our manual goes into great detail outlining all the aspects of antennas, transmitting range and the FCC rules and regulations. You'll be amazed at the exceptional audio quality of the FM10C. Tunes through the entire 88-108MHz band in three separate ranges with a tuned LC circuit. Re-broadcast your favorite music commercial free and with the dynamic range the musician intended, without all that nasty compression the big boys use to make their station sound louder than the competition. Compression produces a noticeably muddier and less dynamic sound. The unit runs on internal 9V battery, external power from 5 to 15 VDC, or an optional 120 VAC adapter (model FMAC) is also available. Includes the matching case & knob set for a professional finished look. Case size 5"W x 1 1/2"H x 5 1/4"D (Note: The FM10C is a do-it-yourself learning kit that you assemble. The end user is responsible for complying with all FCC rules & regulations within the US, or any regulations of their respective governing body)

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Most Helpful Customer Reviews

1 of 1 people found the following review helpful:

5.0 out of 5 stars If you want to rebroadcast digital material throughout your house!, March 21, 2010

509 (Wenatchee, WA) - See all my reviews

This review is from: Ramsey FM10C FM Stereo Transmitter Kit

I built one of these from a kit. They are easy to solder and build. Much better than the CC Crane transmitter, which is the second best choice. It is completely in a different class than the FM transmitters you buy at mass merchandise chains.

There are FCC regulations limiting power of FM transmitters. What I was surprised at given the regulations was the variation in quality.

This is the BEST FM transmitter I could find. I also own the CC Crane FM transmitter which is OK, but significantly below this one in quality. I would not buy a FM transmitter other than one of these two.

FM transmitters are handy for rebroadcasting streaming audio from a computer, TV, or you music collection throughout the house. They work much better in areas with few FM stations. You do need a clear channel to broadcast the FM signal.

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1 of 1 people found the following review helpful:

2.0 out of 5 stars You pay for what you get., December 27, 2008

Techno Geek Guru "Dave" (USA) - See all my reviews

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This review is from: Ramsey FM10C FM Stereo Transmitter Kit

You pay for what you get. It was very easy to build. Nice little project. One problem. The frequencies slightly moves. +/- 0.1MHz over time making you chase it around the dial every few hours.

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4.0 out of 5 stars May be pricey, but it works!, December 6, 2010

Pc Pete "PC Pete" (New Jersey) - See all my reviews
(REAL NAME)

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This review is from: Ramsey FM10C FM Stereo Transmitter Kit

It seems to be getting harder and harder to find a product that lives up to its advertising promises. It's even more upsetting that we, as American shoppers, seem to accept these short-comings and just live with it. Everywhere I go, I see something that didn't perform as the buyer had expected. It sits around gathering dust, until it finally finds its way into the garbage. This item does NOT fall into that category. In fact, it happens to be one of a few products that I purchased this past year, which actually delivers as advertised. It requires some electronics experience, and a frequency counter really helps, so be prepared. Bravo Ramsey.

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Most Recent Customer Reviews

5.0 out of 5 stars OK product, GREAT customer service
Some kit builders have technical issues with how this kit is designed. It WILL drift depending on various factors. If you want a rock solid signal, get the Ramsey FM25B. Read more

Published 11 months ago by Roger Davis

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2-Zone Alarm

epuel.saepuloh@gmail.com (epuel) — Sat, 25 Jun 2011 01:53:00 -0700

2-Zone Alarm

This is a really small alarm that could easily fit inside a pocket. However, I also demanded reliable operation, simple construction and very low power consumption. I started with CMOS logic gates, but was soon forced to abandon the concept after a few unsuccessful (and far too complicated) takes.

Then I suddenly realized that a simple transistor switch might do the job and I was right. As you can clearly see from the schematics, the circuit is utterly primitive and consists of two identical transistor switches. Each has its own alarm LED and they're coupled to a neat 82dB buzzer. The two 1N4148 diodes are used to prevent a signal from one sensor from triggering both LEDs. The sensors are connected to the jumpers. Use either loops of very thin (like 0.1mm) enamel coated wire or normally closed reed switches or even a combination of both.

Since this little alarm is intended to be kept in arms reach at all times, there aren't any provisions for automatic shutdown after a certain period of time. The buzzer will sound until you turn the whole circuit off or connect the wire loop back to the jumpers. The same goes for the two LEDs, each indicating its own zone. Construction is not critical and there aren't any traps for the novice. The two 100n capacitors aren't really necessary, I just included them to make sure that there is no noise interference coming from the long wire loops.

For transistors, you can use any NPN general-purpose audio amplifiers/switches (BC 107/108/109, BC 237/238, 2N2222, 2N3904...). Assemble the circuit on perf board. Together with the buzzer and a 9V battery, it should easily fit in a pocket-sized plastic box smaller than a pack of cigarettes. A fresh battery should suffice for months of continuous operation.

Possible uses:
Tie a wire loop to your suitcase and place a reed switch to the door of your hotel room. If sleeping outside, place the wire loop all around your tent or sleeping bag ten centimeters above ground. Any intruder will tear the loop, thus triggering the alarm.

Fire Alarm Using NE555

epuel.saepuloh@gmail.com (epuel) — Sat, 25 Jun 2011 01:49:00 -0700

Fire Alarm Using NE555

The following circuit is an fire alarm that is quite nice and simple. This alarm function to provide early warning of fires. This alarm provides warning of fire to the user so it can be prevented early.

This fire alarm circuit should be placed in places prone to fire. Fire will cause a fire which caused enough smoke that will reduce the intensity of light to the LDR, which can pass light to the surrounding environment.

With decreasing light intensity will increase resistor value of the LDR and the voltage on PIN2 of IC 555 will drop to be 1-3V. This will trigger the use of bistable mode of IC 555 that cause increased voltage on pin 3 to 9V, which provides voltage to activate the Chip on Board (COB). The signal output from the COB will give sound then be amplified by an audio amplifier IC.

In this circuit, the audio amplifier-wired around IC TDA 2002. The sensitivity of the circuit depends on the distance between the lamp and LDR and the creation of preset VR1. So, by placing the lamp and LDR at appropriate distances, can be varied preset VR1 to obtain optimum sensitivity. S1 reset switch is provided in the circuit to turn off the fire alarm after the fire was noticed by the user. 2 comments Labels: Alarm

DC Laptop Computer PSU/Adapter for Car

epuel.saepuloh@gmail.com (epuel) — Sat, 25 Jun 2011 01:42:00 -0700

DC Laptop Computer PSU/Adapter for Car

Operate your laptop from a car can be done easily if you have a DC to DC Converter, namely a power supply device for changing a DC voltage into another DC voltage is greater (step-up) or smaller (step-down). Changes in output voltage is usually followed by changes that accompany the current. This Step-up DC-DC converter circuit is to be more easily understood, then known as a laptop computer PSU/adapter for the car.
Laptop Computer PSU (Power Supply Unit) to change the voltage of DC adapter car battery to keep the output voltage of about 19V DC with a tolerance of +/ – 0.5V. Input voltage required by the car battery adapter for laptops this can work well between 9.2V-15V, and can supply 5A continuous current with brief excursions up to 10A.

Laptop Computer PSU Circuit Diagram

Car Laptop Computer PSU Circuit Schematic

Laptop computers PSU using SMPS Controller IC UC3843 in the design, which is the fixed frequency current-mode PWM controller. It’s specially designed for Off-Line and DC to DC converter applications with minimum external components. For the voltage amplifier transistors, a pair BD139/BD140 used as a driver for strengthening the IRL2505 MOSFET final transistor.
Use a car cigarette lighter socket on a voltage input section and just plug into the socket. Then use a standard laptop voltage connector and connect at the output voltage circuit. The next step is measuring the voltage output on a laptop computer PSU/adapter circuit. If there is a nominal voltage of 19V DC, It’s ready using the computer PSU.
Read more: Auto Battery Charger – Backup Power Supply

Convert Watts to Amps How to Convert Watts to Amps

epuel.saepuloh@gmail.com (epuel) — Sat, 25 Jun 2011 01:38:00 -0700

Convert Watts to Amps

How to Convert Watts to Amps

Understanding of the convert watts to amps rather approach in measuring the amount of power (watt) based on two components, namely, voltage (Volt) and current (Amps). The equation used to measure the power unit is P = V x I. So the use of the term convert watts to amps is more dependent on the voltage quantity contained. So the logic is to assume that the current (I) is fixed, the greater the voltage (V), the greater the power (P) is produced, and so on.

Convert Watts to Amps-Testing Instrument

As you know, in the conversion of energy, watts are power and amps are the number of electrons flowing at a certain point, which is calculated based on units of coulombs per second. So we can say that you cannot convert watts to amps. However, based on the power equation above, if you have a minimum of at least two of the following three: amps, volts and watts, then the lost can be calculated. Based on this equation obtained a simple relationship of watts are volts multiplied by the current.
In some disciplines, this technique is discussed more in detail, not least for the term convert watts to amps does not cause confusion. For example: an electric switch 220V 6A with the label, it simply means a switch used for voltage 220V with maximum current 6A. Conversion load power through the switch is about the size of 1320 Watts.

Formulation to Convert Watts to Amps

For example, What if the switch is used in the voltage of 110V in connection with the term convert watts to amps? With regard to use the same power load of 1320 Watts, then the power switch can still be used until the maximum current limit of 12A. See the following power equation as a comparison that can be used as convert watts to amps calculator:

P = V x I
P = 1320 Watts

220V x 6A = 110V x 12A = or = 660V x 2A

Convert Watts to Amps Equation

From the description above can be understood that the convert watts to amps are intended to limit the use of a tool that has the ability to power in use, for example, is known for the Power Conversion Table, is a guide for safe use of the intended use and does not cause instant damage. Not on the workings of the instrument, because the design of the instrument has its own calculation done by the manufacturer.

See also: Backup Power Supply – LED Power Supply

Broadband RF Power Amplifier 1.8-30 MHz

epuel.saepuloh@gmail.com (epuel) — Sat, 25 Jun 2011 01:36:00 -0700

Broadband RF Power Amplifier 1.8-30 MHz

Here's RF Power Amplifier for QRP with low cost. This circuit is a broadband one from 1.8 to 30 MHz, so it is "no-tune" and you need only to regulate the quiescent current bias multiturn trimmer of each Mosfets couple. This means also low efficiency (for a lower IMD it is even low as around 20-30%) together with good heat sink + blower system.

HF QRP Linear Amplifier with 2x 2SC2166 + 2x 2SC1969 Push Pull Transistors (13.8V)

The push-pull configuration permits to get a better attenuation of even harmonic frequencies (a good benefit since the second is the closer 2x fundamental freq.). The output stages have 2 separate transformers in each couples so the power supply current does not flow in to the output transformer to avoid saturation and the floating winding helps for balance for harmonic attenuation and stability.

HF QRP Linear Amplifier with 2x IRF510 + 2x IRF510 Push Pull Low Cost Mosfets (28V)

We have emploied also in this low power unit the circuit found in higher power units to stabilise thermically and regulate the bias current around a trusted LM723 IC, the transistors are used only for PTT control. In the first stage Mosfet couple we have used a feedback circuit to optimize gain-frequency response. Without it the low frequency gain is very high, too high: at 3 MHz 50 dB ! and a lower 30 dB at 30 MHz, but with this feedback circuit the overall gain variation is close to a +/-3 dB, a good result.

We tried a similar feedback in the output couple but results where a poorer IMD performance so it has been omitted. We selected Mosfets couples in a simplified way (while not so precise RF matching practice) measuring drain-source resistence: a better way could be to measure in a simple test circuit current drain at a given gate voltage applied for all devices and choose the ones that showed closer current values.

Broadband RF Power Amplifier 1.8-30 MHz in detail

1 Comments:

Pemancar tv dot com said... July 25, 2009 9:32 PM: Nice blog for electronic hobbies! Thank for articles. Pemancar tv dot com http://pemancartv.com

TELEVISION TRANSMITTER KIT

epuel.saepuloh@gmail.com (epuel) — Wed, 22 Jun 2011 15:01:00 -0700

TELEVISION
TRANSMITTER KIT

Don’t string cables through the house! Transmit your VCR or
camera signal to any nearby TV set with great audio and video
quality. You can be the program manager of your own Mini-TV
station!
Typical uses of the TV transmitter:
• Watching one VCR from anywhere in the house
• Using the camcorder camera to watch remote areas
• Hidden camera fun
• Home TV station
• Student TV station
The Ramsey TV6C transmitter features:
• Runs on 12 to 15 volts DC
• On-board whip antenna
• Stable output adjustable to channels 3 - 6
• Clear, concise step-by-step instructions
• Video and Audio inputs compatible with any VCR or TV camera
RAMSEY TRANSMITTER KITS
• FM10A, FM25B FM Stereo Transmitters
• The “Cube” Video Transmitters
• AM1, AM25 AM Transmitters
RAMSEY RECEIVER KITS
• FR1 FM Broadcast Receiver
• AR1 Aircraft Band Receiver
• SR2 Shortwave Receiver
• AA7 Active Antenna
• SC1 Shortwave Converter
RAMSEY HOBBY KITS
• SG7 Personal Speed Radar
• SS70A Speech Scrambler
• SP1 Speakerphone
• MD3 Microwave Motion Detector
• ECG1 Heart Monitor
• TFM3 Tri-Field Meter
RAMSEY AMATEUR RADIO KITS
• DDF1 Doppler Direction Finder
• HR Series HF All Mode Receivers
• QRP Series HF CW Transmitters
• CW7 CW Keyer
• CPO3 Code Practice Oscillator
• VLF1 Low Bander
• QRP Power Amplifiers
RAMSEY MINI-KITS
Many other kits are available for hobby, school, Scouts and just plain FUN.
New kits are always under development. Write or call for our free Ramsey
catalog.
INTRODUCTION TO THE TV6C:
The answer to all your TV and VCR hook-up problems is now in your hands.
Your TV6C TV Transmitter kit is the handy "wireless wire" you can use to
connect up the whole house for TV of your choice!
The TV6C accepts normal video and audio signals from VCRs, camcorders, or
TV cameras and generates a low power TV signal that can be picked up by
nearby TV sets. Please be aware that this kit is a real transmitter and can be
received by others - whether they want to or not! Be especially cautious to not
cause any interference to neighbors or others close by, they are entitled to
enjoy their own choice of programming without any interference from you. Pay
particular attention to the FCC Rules section later in the manual.
In keeping with our spirit of getting folks to build and learn, you'll see that your
kit has step-by-step instructions that carefully guide you to a finished, fully
operating kit. And, you'll not only build the kit, but learn it too! Kit building is a
fun and rewarding way to spend an evening at home, especially on a cold
winter night.
BUILDING YOUR KIT:
Many Ramsey kits can be classified as single evening kits suitable for
beginners or old pros and this one is no exception. But, don't let confidence
get in the way of better judgment. With well over 100 solder joints, even being
right 99% of the time will still allow one error to creep in! Therefore, please
take to heart these following guidelines:
• Use a comfortable soldering iron or pencil for assembly. 30 to 50
watts is ideal.
• Keep your iron tip clean; it will then produce professional, shiny
and reliable joints. Use a damp sponge to wipe your tip before
every joint. Use the wife's kitchen sponge and not your expensive
super-dandy-whiz-bang car wash sponge!
• Good lighting is a must; why strain yourself with poor lighting?
• Take advantage of the fact that our manuals are written in stages,
take a break between sections and check your work before
proceeding on.
• Be on the look-out after each solder joint for a splash, bridge or
errant wire lead that could prove hard to find later.
• Enough said, let's get building....
TV6C PARTS LIST:
CAPACITORS
�� 7 .001 uf disc (marked .001 or 102 or 1nf) [C3,4,5,6,11,14,15]
�� 2 39 pf disc [C7,9]
�� 1 100 pf disc (marked 100 or 101) [C10]
�� 2 68 pf disc [C12,13]
�� 1 220 pf disc [bottom of PC board]
�� 1 2.2 uf electrolytic [C2]
�� 1 100 uf electrolytic [C1]
�� 2 1000 uf electrolytic [C8,16]
SEMICONDUCTORS
�� 1 1N4148 or 1N914 diode [D1]
�� 2 1N4002 diode [D2,3]
�� 4 2N3904 NPN transistor [Q1,2,3,4]
�� 1 2N3866 NPN transistor [Q5]
�� 1 7808 voltage regulator [VR1]
INDUCTORS
�� 1 .15 uh miniature inductor (has brown and green bands) [L5]
�� 2 2.2 uh miniature inductor (green body with 2 red bands) [L2,3]
�� 1 5.5 turn slug tuned coil [L4]
�� 1 IF can style RF transformer (marked 42IF122) [L1]
RESISTORS
�� 1 180 ohm (brown-gray-brown) [R1]
�� 3 1K ohm (brown-black-red) [R1,2,11]
�� 1 3K ohm (orange-black-red) [R4]
�� 3 4.7K (yellow-violet-red) [R5,8]
�� 2 10K (brown-black-orange) [R9,10]
�� 2 75 ohm (violet-green-black) [R6,12]
�� 1 1K trimmer potentiometer (yellow adjuster) [R7]
�� 1 5K trimmer potentiometer (yellow adjuster) [R3]
CONTROLS AND HARDWARE
�� 1 Pushbutton switch [S1]
�� 3 PC mount RCA phono jacks [J1,2,3]
�� 1 DC power jack [J4]
�� 1 Telescopic whip antenna [Ant 1]
�� 1 Printed circuit board [TV6C]
�� 1 Plastic tuning tool “diddle stick”

Elementary technique Radio communications with High frequensi

epuel.saepuloh@gmail.com (epuel) — Fri, 10 Jun 2011 07:26:00 -0700

Elementary technique Radio communications with High frequensi

This to represent a Blog which is very worth to all beginner and also student or wish to learn elekronics.
Because in this Blog study assortedly network form which in wearing at radio-set of communications.
To increase knowledge at that good Telecommunications system In the form of network and also a[n its appliance of him will in debate by mendetail following its experiment.
this Blog utilize will very assisting if us make the most of and correct, all fill in this book there are theory of pda assorted of network and its experiment, have test-drive with result which is very gratify.
Knowledge concerning elementary techniques of Radio communications utilizing this high frequency also very useful bgi all Radio amateur and also candidate of delta,karena this blg earn to be made by guidance as penjunjang of knowledge in the case of have experiment to or upon which test.
Hopefully by studying all that is there is in this blog is we earn to obtain;get glorious efficacy and to all party which
Have assisted compilation of this blog is I submit thank utterance.
All constructive suggestion and criticism I will take in good part for the shake of perfection of blog which I write down.
Letter Symblols
R- Resistor
C- Capasitansi,Capasitor,Condensator
L- Lilitan,Induktansi
E- Tension
I- Current
A- Ampere
V- Volt
Y- Admitansi
Z- Impedance
Q- Coulomb
P- Energy
Po- Output power
Pi- Energy Input
AC- Current of Bolak return
DC- direct current
Hz- Hertzian
Khz- Hertzian Kilo
Mhz- Hertzian Mega
Np- Primary winding
Ns- Circumference of Sekunder
Xl- Inductive Reaktansi
Xc- Capacitive Reaktansi
db- deciBel
UF- Micro Farad
pF- Farad piko
p- Type prisoner
cps- Jolt per second ( Hz)

Elementary technique of Radio communications with High frequensi.

epuel.saepuloh@gmail.com (epuel) — Fri, 10 Jun 2011 06:45:00 -0700

Elementary technique of Radio communications with High frequensi.
This is to represent a Blog which is very worth to all beginner and also student or wish to learn elekronics.
Because in this Blog study assortedly of network form which in wearing at radio-set of communications.
To increase knowledge at that good Telecommunications system In the form of network and also a its appliance of him will in debate by detail following its experiment.
This Blog will very assisting if us make the most of and is correct, all content in this Blog there are theory at is assorted of network and his experiment, have test-drive with result which is very gratify.
Knowledge concerning elementary techniques of Radio communications utilizing this high frequency also very useful To all Radio amateur and also delta candidate, with this Blog earn to be made by guidance as Supporter of knowledge in the case of have experiment to or upon which test.
Hopefully by studying all that is there is in this blog is we earn to obtain;get glorious efficacy and to all party which
Have assisted compilation of this Blog is I submit thank utterance.
All constructive suggestion and criticism I will take in good part for the shake of perfection of blog which I write down.
Letter Symblols.
R- Resistor
C- Capasitansi,Capasitor,Condensator.
L- Circumference, induktansi
E- Tension
I- Current
A- Ampere
V- Volt
Y- Admitansi
Z- Impedance
Q- Coulomb
P- Energy
Po- Output power
Pi- Energy Input
Pi- Energy Input
AC- Current
DC- direct current
Hz- Hertzian
Khz- Hertzian Kilo
Mhz- Hertzian Mega
Np- Primary winding
Ns- Circumference of Sekunder
Xl- Inductive Reaktansi
Xc- Capacitive Reaktansi
db- deciBel
UF- Micro Farad
pF- Farad piko
p- Type prisoner
cps- Jolt per second ( Hz)

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TELEVISION TRANSMITTER KIT

Elementary technique Radio communications with High frequensi

Elementary technique of Radio communications with High frequensi.