| ??? 02/22/03 17:09 Read: times |
#39764 - RE: Designing a Simple Door Answering System Responding to: ???'s previous message |
OK, It's weekend, so let this be the "illegal post" this time and just to get this over with:
one pushbutton DPDT. two small speakers, an amplifier. Speakers, make excellent low fidelity microphones. Pushbutton (in house or at door, your choice - I describe based on PB in house) not pushed: speaker at door to amp input, speaker in house to amp output. Pushbutton pushed: speaker in house to input, speaker at door to output. Erik |
| Topic | Author | Date |
| Designing a Simple Door Answering System | 01/01/70 00:00 | |
| RE: Designing a Simple Door Answering System | 01/01/70 00:00 | |
| RE: Designing a Simple Door Answering Sy | 01/01/70 00:00 | |
| RE: Designing a Simple Door Answering Sy | 01/01/70 00:00 | |
| RE: Designing a Simple Door Answering Sy | 01/01/70 00:00 | |
| RE: Designing a Simple Door Answering System | 01/01/70 00:00 | |
| Thank You ALL | 01/01/70 00:00 | |
| RE: Thank You ALL | 01/01/70 00:00 | |
| RE: Desig Door Answering -REPOSTED. | 01/01/70 00:00 | |
| try to understand my problem | 01/01/70 00:00 | |
| RE: try to understand my problem | 01/01/70 00:00 | |
| RE: try to understand my problem | 01/01/70 00:00 | |
RE: Designing a Simple Door Answering System | 01/01/70 00:00 |