snipped-for-privacy@bbs.cpcn.com wrote:
>> I note that PBX operators had 20 pps dials while the rest of us had 10
>> pps. Some kids experimented and found 20 pps worked at home. Now, it
>> was easy to modify the dial to go faster -- so why didn't Bell have
>> everyone at 20 pps -- faster utilization of equipment? I strongly
>> suspect there were valid technical reasons not to.
During the transition period of deployment to electronic switching, a lot of step-by-step office were provided with DTMF-to-dial-pulse converters so the Bell System and independent LEC could sell DTMF service to subscribers. That implementation was definately limited to something not far above the recommened interval for DTMF tones. As to speeding up dial pulse, that would work on a Crossbar because the origin dial pulse was not driving the switching matrix, where is was on a stepper switch.
Any PBX hooked to a stepper switch had to have its dial pulse limited to 10 pps.