General Theory
Ang D.C. (direct current) ay magsisimulang dumaloy sa - negative, papunta sa + positive.
The negative should reach to positive.
If walang load, ang circuit, or walang ilaw, kung makikita nyo sa picture, ay magiging 0 volts (close circuit) ay mag aapoy ito. O puputok at masusunog ang wire.
Can pass. Makakadaan ang d.c. dito sa resistor.
Can pass. Makakadaan ang d.c. dito sa diode kapag ang - negative ay galing sa k cathode, papunta sa + positive na a anode.
Can't pass. Kapag ang negative ay naggaling sa a, papunta sa k.
Can't pass. Hindi makakadaan ang D.C. dito sa capacitor.
Can't pass. Hindi makakadaan ang D.C. dito
A.C. (Alternating Current)
Kapag A.C. naman ang power supply.
Parehas din ito ng signal ng radio na galing sa hangin or frequency sa hangin.
Can pass. Makakadaan ang signal dito sa capacitor.
Can pass. Makakadaan ang signal dito sa resistor
Can pass. Makakadaan ang signal dito sa diode.
Can pass. Makakadaan ang signal dito.
Why do the
electrons move?
In a circuit the
electrons are
repelled by the
negative charge
at the negative
terminal of the battery and
attracted by the
positive charge at
the positive
terminal.
Therefore the electrons drift
away from the
negative terminal
and towards the
positive terminal
of the battery. When the
electrons reach
the positive
terminal a
chemical reaction
transfers them across the battery
and back to the
negative terminal. Compare the
electrons moving
through the cct. to
ball bearings
rolling down a
slide and the battery to a lift
which raises them
back to the top of
the slide each
time they reach
the bottom. Conventional current flow As stated above the movement
of electrons and therefore the
direction of current flow is
from the negative terminal of
the battery to the positive
terminal. However before the true nature of electricity was
known scientists assumed that
current was the result of the
movement of positively
charged particles and
therefore that current flowed from the positive to the
negative terminal. This
(incorrect) convention is still
used today and is called conventional current flow. When discussing the true
nature of current we call it electron flow. In general conventional current flow is
indicated on cct. diagrams and
true electron flow is used
when we describe how an
individual component works.
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Resistor Color Coding
Rules of color Coding
1. Color nearest to the point as a first band.
2. If the 3rd band is silver, gold, black or brown the resistance value will be in OHM (hundred).
3. If the 3rd band is red, orange or yellow the resistance value will be in kilo (thousand).
4. If the 3rd band is green, blue, or violet the resistance value will be in mega (million).
5. If the 3rd band is gray or white the resistance value will be in giga (billion).
eto picture sa taas ang tinginan, makikita sa multiplier sa brown hanggang silver sa may 10 ay may makikita kayong numero, yung ay katumbas ng idadagdag na zero sa 1st at 2nd band. 
Unit of Resistor Symbol
Ohm - Hundred
K - kilo - thousand
M - Mega - million
G - Giga - billion
Example.
1st, 2nd, multiplier,
1. Orange, orange, brown = 330 ohm (hundred pa lang)
2. Brown, black, orange = 10,000 = 10k (dahil thousand na)
3. Brown, green, yellow = 150,000 = 150k (dahil thousand na)
4. Yellow, violet, red = 4,700 = 4.7k (thousand)
5. Red, black, black = 20 ohm (hundred pa lang)
6. Red, black, gold = 20 x 0.1 = 2 ohm
7. Red, brown, silver = 21 x 0.01 = 0.21 ohm (hundred)
8. Red, brown, white = 21,000,000,000 = 21G (billion na kasi)
9. Red, brown, violet = 210,000,000 = 210M (million na kasi)
Tolerance - a percentage by w/c actual value of resitor, capacitor or other electrical unit may be differ from nominal value either plus + or - minus.
Madalas nating makikita ito sa resistor. Ang 4rth band nya ay tolerance. Malalaman nating good ang resistor kung hindi bababa or tataas sa tolerance percent sa actual reading.
Example.
Resistor color code
orange, orange, brown, gold
= 330 ohm -+5% ang tolerance
330
x 5%
________
= 16.50
So plus or minus 16.50 sa 330.
330 + 16.5 = 346.5
330 - 16.5 = 313.5
So kung ang reading nyo sa tester ay ay nasa pagitan ng 346.5 at 313.5 ay good ang resistor nyo. Kung lumampas or bumaba, ay deffective ang resistor.
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Multimeter
Ang pinakataas ng scale na makikita sa multimeter ay para sa pagsukat ng resistance = ohm. Ang zero ay nasa kanan, at ang infinity ay nasa kaliwa. So ang pagbasa ng reading ay pakaliwa.
2 lang ang dapat tandaan sa pagbasa ng reading. Ang una ay ang pagpili ng range (kung X1 or X10), tapos ilagay ang needle sa zero. Magagawa ito sa pagdikit ng test prob, ay i adjust ang knob (zero corrector) at itapat sa zero.
Ang pinakamababang range ay X1. Ang pinakamataas ay X10k.
Ang X1 range ay ginagamit kung magsusukat ka ng resistance na mas mababa or hindi lalampas sa 500 ohms.
X10 naman kung mas mababa sa 1000 ohms
X1k kung mas mataas 1000 ohms.
V.O.M. - Voltmeter, Ohmmenter, Milliammeter= the ohmeter use for measuring resistance. The topmost scale of multi meter is for ohmmeter reading, so the attention would be focused only the scale for reading resistance, zero is located on the right side of the meter infinity is on the left side the two should be taken before making any resistance measurement the first step is to select a proper range or multiplier in the function selector.
The second step is to adjust the needle or the pointer to zero reading. This done by shorting together test probs and turning slowly the ohmeter adjust knob until the needle is pointing to zero reading. Zero adjustment should be done on any multiplier range.
Accuracy of measurement therefour multiplier range in this multi-tester if SANWA type model range are X1, X10, X1k, X10k so the lowest range is X1 this range is used for measuring low resistance not exceeding 500 ohm.
For resistance measurement or less than 1000 ohm X10 range is more accurance.
External Part of Multi-Tester.
1. Indicator cover
2. Meter scale
3. Meter pointer
4. Zero corrector
5. Range selector
6. Zero ohms adjust
7. Test prob
8. + socket
9. - socket
10. Output jack
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