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Question
What is the difference between FDM and WDM?
 Question Submitted By :: Electronics-Communications
I also faced this Question!!     Answer Posted By  
 
Answer
# 1
FDM IS USED FOR ANALOG SIGNALS GENERALLY FOR THE SIGNALS
TRANSMITED THROUGH TWISTED PAIR CABLE.
WHILE
WDM IS USED FOR SIGNALS TRANSMITTED THROUGH OPTICAL FIBER
CABLES.
BOTH ARE SAME BUT USED IN DIFFERENT AREAS.
 
Is This Answer Correct ?    35 Yes 2 No
Sanjay Kumar Pal
 
Answer
# 2
FDM > Frequency Division Multiplexing
WDM > Wavelength Division Multiplexing
 
Is This Answer Correct ?    32 Yes 12 No
Aby Perumpanany
 
 
 
Answer
# 3
in fdm data transmitted based on the particular frequency
and in wdm data transmitted based on the particular wavelength .
fdm is used in twisted pair cable and wdm is used in fiber
optic cable .
 
Is This Answer Correct ?    13 Yes 5 No
Vinit92
 
Answer
# 4
their is no difference between FDM and WDM because wavelenth is inversly proportional to frequency. but generally when we are working on optical domain then we consider WDM because

i) we have limited source to genrate light using LED or LASER. using this we can genrate light easily and then passthourgh prism to get different wavelength. we can not genrate such high frequency.

ii) to analysis of such high frequency in CRO is not possible that why we are using WDM when we r working on Optical domain


Regards,
Raj Hakani
(M.tech Communication)
Nirma University
 
Is This Answer Correct ?    8 Yes 3 No
Hakani Raj
 
Answer
# 5
yes 
Is This Answer Correct ?    8 Yes 12 No
Sandhi
 

 
 
 
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FULL FORM OF SCR RRB 14
(1) Instrument is a device for determining (a) the magnitude of a quantity (b) the physics of a variable (c) either of the above (d) both (a) and (b) (2) Electronic instruments are preferred because they have (a) no indicating part (b) low resistance in parallel circuit (c) very fast response (d) high resistance in series circuit (e) no passive elements. (3) A DC wattmeter essentially consist of (a) two ammeters (b) two voltmeters (c) a voltmeter and an ammeter (d) a current and potential transformer (4) Decibel is a unit of (a) power (b) impedance (c) frequency (d) power ratio (5) A dc voltmeter may be used directly to measure (a) frequency (b) polarity (c) power factor (d)power (6) An accurate voltmeter must have an internal impedance of (a) very low value (b) low value (c) medium value (d) very high value (7) The insulation resistance of a transformer winding can be easily measured with (a) Wheatstone bridge (b) megger (c) Kelvin bridge (d) voltmeter (8) A 100 V voltmeter has full-scale accuracy of 5%. At its reading of 50 V it will give an error of (a) 10% (b) 5% (c) 2.5% (d) 1.25% (9) You are required to check the p. f. of an electric load. No p.f. meter is available. You would use: (a) a wattmeter (b) a ammeter, a voltmeter and a wattmeter (c) a voltmeter and a ammeter (d) a kWh meter (10) The resistance of a field coil may be correctly measured by using (a) a voltmeter and an ammeter (b) Schering bridge (c) a Kelvin double bridge (d) a Maxwell bridge (11) An analog instrument has output (a) Pulsating in nature (b) Sinusoidal in nature (c) Which is continuous function of time and bears a constant relation to its input (d) Independent of the input quantity (12) Basic charge measuring instrument is (a) Duddel's oscillograph (b) Cathode ray oscillograph (c) Vibration Galvanometer (d) Bailastic Galvanometer (e) Battery Charging equipment (13) A.C. voltage can be measured (using a d.c. instrument) as a value obtained (a) by subtracting the d.c. reading from it's a.c. reading. 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