[sci.electronics] Tone/Memory Help Needed

guhsd000@crash.cts.com (Paula Ferris) (03/24/88)

I'm working a project to keep my spare time occupied, but I need some help and suggestions.

I'm making a chat line for private use, and have a working prototype, but it's not good enough.

I need to add a tone encoder/decoder circut with memory to switch (Either electronically or mechanically, electronic prefered) line on and off, and to accept passcodes.  

I hope to have passcodes of 10 digits or so.  As it designed now, anyone who called the dialup is instantly clicked over, and a timer started.  When the 555 expires, it hangs up.

One line would be for System Operators only, who could dial in codes for differant functions, mainly hanging up lines, and paging a operator at the machine.  There must be a tone filter out tones on the line so button-pushers and the operator dialing in 
instructional codes would not come accross on the conversations.

Does anyone out there know of any good books or other resources with schematics exsits?  If so, where can I get a hold of it?

Any suggestions would be welcome, This just how I thought of it.  I would hate to re-invent the wheel if I don't have to.  I'm trying to keep this cheap as possible, as I don't have alot of bucks to pour into this.

BTW, I'd expect the memory to hold about 150 codes to 200, and hopfully be battery backed.  It put the codes in, I'd like to use a key pad on the machine, and hit something like * to enter a number, and # to delete one.

Thank You for aborting this message.

   PAULA FERRIS

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