come with me to understand telephone circuits

Thread Starter

farra

Joined Jun 24, 2005
1
Hi i'm samy farra, i 50% English language, nowadays i interested in telephone circuits analysis, that is i have more than 10 circuit diagrams of telephone devises and i spent most of my time to understand how they were designed.
many persons are happy when they only build circuits that others design without any attempt to understand how these blocks work, this is not OK and leads to bad results in the future of all of us. so i shall start with telephone circuits for discussion and invite all of you to put what you know even if it is not so important information, i shall also share with you what i know about with schematic diagrams, and we all must do some research and finally i can put all these info after editing in a new page for reading and as a reference, then starting another subject which may be AM-FM radio receiver.
thanks.
 

mozikluv

Joined Jan 22, 2004
1,437
Originally posted by farra@Jun 24 2005, 03:36 AM
Hi i'm samy farra, i 50% English language, nowadays i interested in telephone circuits analysis, that is i have more than 10 circuit diagrams of telephone devises and i spent most of my time to understand how they were designed.
many persons are happy when they only build circuits that others design without any attempt to understand how these blocks work, this is not OK and leads to bad results in the future of all of us. so i shall start with telephone circuits for discussion and invite all of you to put what you know even if it is not so important information, i shall also share with you what i know about with schematic diagrams, and we all must do some research and finally i can put all these info after editing in a new page for reading and as a reference, then starting another subject which may be AM-FM radio receiver.
thanks.
[post=8694]Quoted post[/post]​

pls be specific on what area of the telephone circuitry you are interested so the knowledgeable members can respond appropiately. it's hard to guess what you want. :p
 

ahsan

Joined Jun 26, 2005
5
Well Farra I appreciate your interest in Telephony circuits. I must say we've to specify different blocks of a Telephone set first.

1)Incoming call alerter
2)Speaker and driving circuits
3)Keypad
4)LCD and its Controller
5)Memory storing device

I being an electrical Engineering students always believe in divide and conquer and believe me I design my own circuits with minimum of resources with sound understanding.So I'll advise u to follow step by step and we'll be successful in the end.
 

yong

Joined Feb 23, 2008
27
Any know how does this circuit works...basically when the phone rings, it will toggle the relay to activate some application.
 

Audioguru

Joined Dec 20, 2007
11,249
Telephone answering machines, old dial-up modems and Fax machines have an opto-isolated ringing detector circuit. Look at them in Google.
 
Top