[GreenKeys] Telco Tones

[Larry Tighe]

I found the two filters/channel elements in the Model 28.

The tones 1070/1140 and 2260/2330 are 70 cycles apart thus the shift.  Being 
an "RO", I suspect the higher tones are for answer back transmission.

Question:  Are tones on a line called "carrier"?  I originally thought the 
carrier carries the AFSK, but it appears the AFSK is called "carrier".

If AFSK is the carrier, then I have no sweat with an ST-8000A being the TU 
and using it as a KSR...it originally has the KB covered so as to be an RO.

Thanks for any input on carrier.

lar
Larry
www.antiquetelephone.com