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Nguye n Lo c. Bi nh has written:

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10y ago

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Subtraction of 2d array in java?

looda le lo mera


What did LO Colvin and Gustav de Laval invent?

the milking machine in 1860


Direct starter would normally be applied for a 2 kW electric motor?

if the load is relatively lo inertia then no problem


Why local oscillator frequency are higher than signal frequency?

It doesn't have to be; you can do it either way.If it's part of a transceiver, then the LO is usually placed on the side of the Rx freq that'sopposite the Tx freq, so that leakage from the Tx oscillators can't produce Rx phantoms.Another thing to watch out for ... depending on the Rf band and the IF, you wouldn't wantthe LO to ever operate AT or near the IF frequency. That could really play havoc with theRx discrimination.For example ... an old AM radio, covering 0.55 to 1.6 MHz, with an IF of 0.455. If you put theLO on the low side, then at or near 910 on the dial, the LO runs at 455 to produce an IF at 455 !There's this loud LO blasting out at 455, while the IF strip is trying to work with this tiny receivedsignal at 455 at the same time. Not good.


Why transmit frequencies are allocated higher frequencies than that of receive frequencies?

That's not the case at all. A moment's thought will show you why that's impossible ... no 2-way linkcould work if that were the rule.Picture two communications sites talking to each other by radio over a "duplex" link ... meaning thatthere's 2-way communication; each terminal can hear the other and talk to the other.In order for them to communicate with each other, each receiver has to listen to the frequency wherethe other end is transmitting.If one site transmits HI and receives LO, then the opposite site had BETTER transmit LO and receive HI,otherwise neither site can hear the other one !It must be that exactly half of all the duplex terminals in the world transmit HI and receive LO,and exactly the other half must transmit LO and receive HI.