Consumer Electronics

The horizontal sweep of an oscilloscope is in time per division or seconds per division.

A diode is a component that lets current flow in only one direction. A zener diode has an additional property that current will begin to flow in the reverse direction when a reverse voltage is applied above a certain threshold. This property is generally used for voltage regulation purposes. A diac has similar voltage regulating properties but behaves the same in both directions - current will flow through it when a voltage above it's threshold voltage is applied in either direction. It is therefore useful in AC as well as DC circuits. Below the threshold voltage the diac will be off - no current will flow. A diac is electrically similar to a neon bulb or gas regulator tube.

This is the European "Pro-electron" numbering system compared with the US JEDEC system (2N etc)

First - Letter

A = Germanium Device
B = Silicon Device
C = Gallium Arsenide

Second - Letter for A/B/C devices

A = small signal diode
C = small signal general purpose transistor (for audio or slow speed switching)
D = power transistor (audio and low frequency applications_
F = small signal RF transistor
T = SCR / Thyristor
U = power transistor for switching applications
Y = rectifier diode

Third + Fourth + Fifth - Unique identifier number

Some manufacturers put some significance on the number. For example Mullard/Philips treated the second digit of 4 meaning NPN Lockfit case and 5 meaning PNP lockfit. Many used 6 for TO92 cases.

An optional letter followed indicating a gain grouping ... typically A being lowest, B middle and C highest

Different manufacturers created similar transistors with different type markings.

e.g. BC107 BC167 all functionally very similar.

So, the BC147 is a Silicon small signal audio transistor with a "Lockfit case" originally manufactured by/for Philips/Mullard. A viable replacement today, if you can't find a 147 is a BC547 If there's a gain grouping letter, you need to match the gain grouping either by a comparable letter, or by testing. Careful with the pinout.

There are a cluster of similar transistors ...

So, the BC147 is one of a cluster of 3 similar transistors ... BC147/148/149. BC147 has ratings of VCE 50, VCB 45 ICMAX 100 hfe 125-500
BC148 has ratings of VCE 30, VCB 20 ICMAX 100 hfe 125-500
BC149 has ratings of VCE 30, VCB 20 ICMax 100 hfe 240-900 Noise 2dB

Lockfit transistor pinout (wideface down)
B
E C

BC547 pinout (flatface down)

E B C

laminator

1. Electricity can cause pollution if it is generated by fossil fuels, or nuclear energy. It can affect animal life if it is generated by hydroelectric dams or tidal power.

2. Electric devices, circuits, conduits, and transmission lines present a shock hazard to people: those who use it, those who work with it, and those who provide it. Short circuits and sparks also present a fire hazard.

3. High voltage lines are thought to cause hazards to plants, animals and people who live near them, because they produce magnetic and EMF fields.

4. People who have become dependent solely on electricity may be unable to function without it in an emergency.

A simple (and I do mean simple) formula is approximately 100 watts per amp. So, 700 watts total equals 7 amps, with 8 amps to spare on the 15 amp circuit breaker.

It's really a bit more complicated than that, considering rms voltage/current equation, but it's close enough for government use. ;)

I think you mean 1/4W and 1/8W ratings for resistors. If so, it indicates wattage (power dissipation) ratings for resistors. Basically this specification for resistors shows maximum power that can be allowed to dissipate in the resistor. Wattage does not as such affect the value of resistor (it should remain with in % tolerance value specified when operated within specified wattage).

( P=I^2 x R). or (P = I x V)

P=Power, I = Current, R= Resistance, V = Voltage Once you know the power rating, you can calcutate how much current can be passed through a resistor of specific value without causing a damage to the component or circuit. For long term reliability always it is advisable to design with a margin (for 1/4W or 250mW e.g. design so that it is always certain % less than the rated e.g. operate at 200mW or less) - Neeraj Sharma

I had the same thing happen. I replaced the batteries in the outdoor sensor, but just got the two dashes on the clock that should display the outside temperature. After I replaced the batteries in the clock itself, the outside temperature then showed up properly on the clock. I also took all batteries out of both devices and replaced them in the order recommended in the directions on the back of the clock. I hope that helps.

A manual typewriter cannot have multiple fonts being used at the same time. The cylindrical type heads of a manual typewriter were also replaced with a spherical type ball in the electronic version.

3.14159265358979323846264338329...etc....... and ends with 1

The advantage of using a cellphone is that it is portable and affordable. It therefore makes communication easier and faster. The disadvantage is that it may lack privacy and may be very costly.

basically a diode flows an exponential curve Vs current if you try to double the voltage drop by increasing the voltage it should self destruct

ABC

For CB's that are both modern and "legal" a frequency counter does not help much at all. However if you have an older radio with continuous tuning (dial with a needle) or are tuning "out of band" (using an illegal modified CB) you may find a frequency counter very useful. No,All the frequency counter does is match the frequency to the radio, to tell you how accurate the radio is, if it is a quality radio it is a waste of time for a more efficent CB radio you would want a RF meter to match the antenna to the radio, this would give you max signal when you key the mike, most of the radios that I have ever used have a signal strength right on the radio. All radios are designed to reject all frequencies except the one it's tuned to. Transmitter accuracy and receiver accuracy are both important for clear reception. CB radio uses 26-27 Mhz with a channel spacing of only 10Khz. If your transmitter's frequency is 5Khz too high and the person you're trying to talk to has a receiver that is a few Khz too low, you may not be able to talk to them at all or the sound will be distorted. All radios can be aligned. Better quality radios will not necessarily hold that alignment better. Antenna matching will affect how strong the signal is but not the frequency accuracy of that signal.

A frequency counter will tell you what frequency you are on. It does not help the average CB radio. But it does do a lot for modified cb's with extra channels. A Frequency counter also comes in handy if you are talking on side band, it helps you remember where to set the dial, and makes tuning someones signal in much easier. A Frequency counter will help if you need it. If you dont need it it is a waste of money.

~TeZ~

I've got a little black rca remote, and sanyo tv code wasn't in the manual. Found it manually "052". our other rca remote had 1048 for our sanyo tv.

other codes for sanyo are..

3digit codes:

004, 017, 021, 039, 048, 049,

056, 057, 058, 073, 080, 107,

162, 169, 180, 196

4digit codes:

1004, 1047, 1048, 1049, 1073, 1078, 1080, 1089, 1095

1107, 1121, 1129, 1162, 1163, 1169, 1180, 1196

the first code you dial in your mobile.

Dr. Carl Gassner Jr. in 1886

If you are trying to make a computer joystick, the way you would do it would depend on the type of signals you are trying to produce. If you want a simple digital joystick, you would use switches for each main position, and a pivot and arms to reach the switches. If you want an analog joystick, you would need to create a yoke to turn 2 sets of potentiometers (basically volume controls). A modern digital joystick might use the potentiometers and an A/D converter. Then you would have to have switches for the fire/control buttons. Then you would need the correct cables and wiring. If you create for USB, you'd need extra circuitry to make it USB compliant (and that is beyond the scope of this answer).

Im not really sure, but a wise man once told me, "If you think something may be wrong, then don't do it" Praise to you grandpa!!!

1st you need to know where the leak is. The only time a copper fitting or brass fitting will fix a leak is in the watersupply connection.

hi guys the second telephone ever invented was the telephones for the deaf invented around 1880. then was the candlestick telephone invented in the year 1900. i hope that helps.

You fix discs by using a kit with a series of abrasives, from course to light, to wear down scratches - step by step - to a smooth finish. Professional systems use multiple abrasives, consisting of different hardness and shapes (sharp to smooth). Regardless of product or system used, the key is to use a series of abrasives (more than one stage) to gradually bring the plastic back to a polished surface. If you want to remove all scratches on your disc, take a look at the 5-stage Scratch Pro repair kit. It will bring the disc back to its original shine and you will have a kit on hand to fix the next disc. Also do a search for scratch repair to see what is out there in your area. To do a targeted search, use the + sign in front of the search words +disc +scratch +repair From Merlin's Table's site… "CENTRE RING DAMAGE... The ring around the centre of the disc contains the data that tells the console player or CD player what the disc is all about. When this ring is scratched or scuffed or hazy, the disc will not register in the console. The ring is on the non-labeled (data/playing) side of the disc, around the centre hole. Look closely and you will see a small shiny band in this highly reflective area. This area and any other scratches on this side of the disc can be fixed using your repair kit."