POTS
Techology Sequence
- Local Battery
- Common Battery
- Touchtones
- Cellular Service
- Integrated media device (aka "smartphone")
Parts of a Telephone*
*Local-battery type
A telephone is TWO devices!!
- A talk circuit
- AKA "bearer"
- A signal circuit
The hookswitch toggles between the two
Hookswitch DOWN: signal
Hookswitch UP: talk
Talk Circuit
- Transmitter
- Receiver
- Battery for power
- Connecting Line
- Induction Coil
- Provides the "magic sauce"
- Direct current
Signal Circuit
- Generator (magneto)
- Gongs (bells)
- Alternating current
- It can SHOCK you!!
Historical Sequence
- One-box wall set
- Candlestick
- Grab-a-phone
- Desk set