As other people have mentioned, stay away from FLEX. It's way more work then necessary. Pocsag should be able to do what you want. The code for a 16c84 based pocsag encoder is available here: http://www.users.interport.net/~carlott/projects.html The code is some early stuff of mine and some of the routines are downright terrible. But it does work! Encoding pocsage is not that tough, you just have to keep the timing tight. I'm in the process of re-writing the code to streamline a bit and add some additional features. It would still be a good place to start. In my project I deliberately left out details on the rf end of things. Here however are a couple of things to investigate. This is all very United States oriented, mileage may vary in your country of interest. Don't even bother to try to tranmit on existing pager frequencies. There are sources available to re-crystal a pager onto other more useful frequencies. Just try to make get those frequencies close to the original pager receiver freq so that the pager's RF front end won't loose too much sensitivity. Re-crystal a cheap 900 mhz pocsag pager onto the low power 915/916mhz control band (US freq./ actual freq. may vary for your country). Then use a RFM/lynx/dvp/whatever low power transmitter on the same freq. I'm not sure which of these x-mitters are capable of sending the direct fsk you need to modulate the signal, time to do a little research. Or, if you are a licensed ham radio operator you could re-crystal the pager onto one of many amateur frequencies. You could then transmit with some real power, but you would also have to add into the transmission some voice or morse code to identify the transmitting station (not a big deal), people are doing this all the time.Note that this is not an acceptable commercial solution. Depending on the area you are in you could get a business band radio license and re-crystal for that. It's not that hard to get a low power license (<2watts in the uhf band). There are less restriction on what you can transmit in the business band then there are on the amateur frequencies. Back on the ham subject, you also may want to look at the following website; http://www.kantronics.com The have a packet TNC that also does pocsag (kpc-9612), along with some dedicated paging encoders. Hope these rambling were of help.... But trust me about the FLEX. At 11:12 AM 9/1/1999, you wrote: >Hi all! > >I am designing a PIC-based alarm system. The instrusion detection is easy. >The local alarm is very easy too. > >But I'd like to include some form of remote alarm. I was thinking about a >regular pager as the alarm receiver, but I don't know how to transmit data >to it. Does anybody knows how to send an alert to a pager? Please, without >using the phone. I mean a Pager Transmitter like the one that carrier >companies have, only smaller. Provided that one can build/adquire the >equipement, is it legal? Does the FCC allows you to transmit in the Pager >frequencies? Or are they restricted? Do you need some kind of licence? carl -------------------------------------------------------- Henry Carl Ott N2RVQ carlott@interport.net http://www.interport.net/~carlott/ -------------------------------------------------------- You're entitled to your own opinions. You are not entitled to your own facts.