My statement about the definition of "Standard CTCSS Modulation" is correct, and thank you for confirming that. As others have pointed out, manufacturers are not necessarily bound to comply with TIA standards. I guess the real issue is, why should any manufacturer set CTCSS deviation at two to three times what is necessary for reliable decoding?
73, Eric Lemmon WB6FLY -----Original Message----- From: [email protected] [mailto:[EMAIL PROTECTED] On Behalf Of nj902 Sent: Saturday, July 19, 2008 6:59 PM To: [email protected] Subject: [Repeater-Builder] Re: PL Problem Naahhh.... In TIA-603-C paragraph 1.3.5.3 is in the "Definitions" section not in the "Standards" section. 1.3.5.3 refers to the "Definition" of the "standard test modulation". The correct section for the actual "Standard" is under: "Standards for All Equipment" 3.4.17, "Transmitter Subaudible Deviation" 3.4.17.2 "Standard" In that table, for rated system deviation of +/- 5.0 kHz, the deviation limits are 500 to 1000 Hz. Hence it follows that the midpoint would be 750 Hz deviation which is the value most of us use as a target. ---------------------------------------------------------- --- In [email protected] <mailto:Repeater-Builder%40yahoogroups.com> , "Eric Lemmon" <[EMAIL PROTECTED]> wrote: " No, that is not correct. TIA-603-C states that the Standard CTCSS Modulation for an emission of +/- 5 kHz deviation, that is, a 20K0F3E emission, "is" 500 Hz. There are no "at least" or "minimum" qualifiers. This is in Paragraph 1.3.5.3. 73, Eric Lemmon WB6FLY"
