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)
----- Original Message -----
From: <[EMAIL PROTECTED]>
To: <Repeater-Builder@yahoogroups.com>
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: Repeater-Builder@yahoogroups.com
> 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
>
>
>
>
>
>
>
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