Commodore modem 300 User Manual page 66

Minimum high level output voltage VCC -.1V @ 20uA
Maximum low level output voltage .1vv @ 20uA
Mark = High
Space = Low
AC Specifications
Modem Frequencies
Originate:
Transmit: Space = 1070Hz, Mark = 1270Hz
Receive: Space = 2025Hz, Mark = 2225Hz
Answer:
Transmit: Space = 2025Hz, Mark = 2225Hz
Receive: Space = 1070Hz, Mark = 1270Hz
Maximum frequency error: 4Hz
Maximum output power: -9 dBm
Minimumoutputpower: -15dBm
Carrierdetect threshold: -44 dBm on/ -47 dBm off
Maximum audio input voltage: 2.6V ACpp
Maximum frequency error: 1 %
Maximum output power (DTMF pair): +1 dBm
Maximum output power (either tone): 0 dBm
Minimum output power (low group): -8.5 dBm
Minimum output power (high group): -6.5 dBm
Touch Tone dialing rate: 100 ms on/100 ms off
Rotary dialing rate: 40 ms make/ 60 ms break
Environment
OperatingTemperature: 0to50°C
Storage Temperature: -20 to 70°C
Humidity: 20to95% RH(non-condensing)
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