You're right John ... ---- Original Message ---- From: [EMAIL PROTECTED] To: [email protected] Subject: Re: [Repeater-Builder] Acoupleofquestionsabouthardline ?? Date: Mon, 24 Apr 2006 18:27:47 -0400
>The MF or Muti Freq. tones were even numbers 700 + 900, >700 + 1100, 900 + 1100 for 1, 2, 3 then they used 1300 1500 1700 >with the other low group for the rest. > >This was known as "In band signalling" and is what the operators >used on their tandem trunks (Inter office circuits) to place long >distance calls. An idle circuit had 2600 tone on it >also known as SF (Signalling frequency) > >73 John VE3AMZ (Retired Bell Canada) Later, Motorola studied for a human ear sensitive tone to use on their pager alerting ... and also settled on 2600 Hertz. The first pagers that came out drew a lot of customer complaints - as when the customer was on a long distance call and his pager alerted him, his long distance call got dropped. Fast forward ... apparently, the 2600 Hz alert tone was the same tone Telco used as a disconnect tone. BEEP - BLAST - your call got dropped ... Neil > > > >----- Original Message ----- >From: <[EMAIL PROTECTED]> >To: <[email protected]> >Sent: Monday, April 24, 2006 5:13 PM >Subject: Re: [Repeater-Builder] A couple of questions about hard line > > >> >> Hi, I believe the term Multi-Frequency was used to describe the >> early AT&T inter office toll dialing scheme. >> >> The tones used were not the tones you hear on your telephone - >> but another completely different group. >> >> If I dig around here far enough, I may still have the >> information. >> >> Mike, WA6ILQ, may be able to detail this better than I or, >> perhaps, a retired AT&T or Western Electric systems engineer. >> >> Neil - WA6KLA >> >> >> >> ---- Original Message ---- >> From: [EMAIL PROTECTED] >> To: [email protected] >> Subject: Re: [Repeater-Builder] A couple of questions about hard >line >> Date: Mon, 24 Apr 2006 14:08:09 -0700 >> >> >And Touch Tone (tm) is a registered trademark of AT&T. Everyone >else >> >has to use DTMF or MF depending on which side of the planet you >are >> >on. >> > >> >On 4/24/06, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote: >> >> >> >> Of course !! >> >> >> >> CG = Channel Guard - General Electric >> >> >> >> PL = Private Line - Motorola >> >> >> >> QC = Quiet Channel - RCA >> >> >> >> All are commonly referred to by CTCSS >> >> >> >> Neil - WA6KLA >> >> >> > >> >> >> >> >> >> >> >> Yahoo! Groups Links >> >> >> >> >> >> >> > > > > > > >Yahoo! Groups Links > > > > > > Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
