AM and FM Radio BroadCasting Station
I have some very basic questions that is also my assignment
1- What are the essential parts of an AM Radio Station (for Medium Power transmission)?
2- What are the essential parts of an FM Radio Station (for Medium Power transmission)?
3- How can we say , it is medium power? i mean range.
waiting for your reply
Thanks
umair
Dear umair
Hi
If you're referring to a transmitter , for an AM : at first a crystal oscillator . and then a low power amp , and then a high power amp .
it was for RF signal ( carrier ) and for Audio signal ( message ) we will have a preamplifier . and then a power amplifier . and then we will use this message signal , in series with DC power line , simply . and at last a matching network . and if you need higher powers , a combiner and gang of transmitters .
And for FM : create an FM signal , and then , some class C or E or F , stages , as pre amplifier , and then some power amplifiers . The process of FM signal , will be easier than AM , because the amplitude isn't important .
Best Wishes
Goldsmith
thank you for your reply!
I am looking for a block diagram. Is this the one i should look for AM transmitter?
http://www.maxmcarter.com/classexmtr...amblock640.gif
and
combiner = Modulator?
through searching i found out
low power transmitter= less 10Watt
medium= 10W-- few hundreds of Watt
High = in kWatt
is it true?
Thanks
At first let me talk about combiner , no it doesn't mean modulator , consider that you have some transmitters and you want to increase the out put power . can you use some transmitter in parallel ? of course yes , but not easily . you have many ways , such as a master/slave feed back , but at very high powers ( around 500KW ) it isn't a good choice . so you have to use a combiner , a combiner , means a magnetic section which will sum , the out put of your transmitters , magnetically . i hope you got my mean .
And about medium and low and high , i didn't outbreak myself with these definitions , because it isn't important . for example suppose that a company give you an offer for a transmitter , they won't tell you , to make a madium power or low power transmitter . they'll tell you , for example we want a 1 MW or 800 KW or less or higher , transmitter in the range of ( e.g 30MHZ ) and impedance of antenna is around 50 ohms .
Best Wishes
Goldsmith
