Ian, The reference given was for the purpose to read about modulation and Mark and space frequencies and not for design. if any one wants to design that is a different story,
AMD had a FSK chip few years ago AM 7910, Jan At 10:00 AM 4/30/99 -0700, you wrote: >Jan, > >You are correct it is 1200 bps FSK, but also half duplex. > >In my opinion the 202 in the ARRL handbook will not function very well in a >POTS connection. The TX/RX filtering is not adequate. If I remember >correctly that example is intended to be used in RF transmissions of high >speed RTTY. > >Duane > > > >>First of all the 202 modem is 1200bps FSK modem, >>You can find a lot of information in ARRL amateur radio Handbook. >>The modified version of 202 modem is used for Ham Radio packet operation. >>Jan >> >> >>At 07:59 AM 4/30/99 -0400, you wrote: >>>From: "Ian Chapman" <[email protected]> >>> >>>Hi, >>> A friend of mine would like to know about the old data set 202. >>>Often called the penny whistle modem. That's FSK 300 bit/sec originating >>>and answering frequencies really antique stuff. The older ones had acoustic >>>data couplers. Any help I can dig up information for him would be greatly >>>appreciated. >>> >>> Regards Ian. >>> >>> >>> >>Janusz Purwin >>Xedia Corp >>119 Russell St. >>Littleton Ma 01460 >>Tel 978-952-6000 ext 166 >>Fax 978-952-6090 >>email; [email protected] > Janusz Purwin Xedia Corp 119 Russell St. Littleton Ma 01460 Tel 978-952-6000 ext 166 Fax 978-952-6090 email; [email protected]
