| Telephone audio amplifier |
Amplifies telephone audio signal. |
2.89 |
1,646 |
| Telephone ringer |
Audio and visual telephone ringer. |
2.90 |
1,494 |
| LED monitor for phone line |
Turns LED ON when phone line is in use. |
2.95 |
1,323 |
| Telephone line status |
Another device for telephone line status indication. |
2.92 |
1,197 |
| LED-blink monitor for phone line |
Blinks LED while phone line is in use. |
2.90 |
1,158 |
| Telephone hold with music |
Keeps phone line open and plays audio signal on it. |
2.94 |
1,073 |
| Phone line in use indicator |
Very simple device with two LEDs as indicators. |
2.93 |
1,063 |
| Phone ring generator v1 |
Generates voltage across phone line in order for phone to ring. Works on 12V. |
2.91 |
1,051 |
| Phone ring generator v2 |
Generates voltage across phone line in order for phone to ring. Works on 9V. |
2.89 |
1,050 |
| Telephone line guardian v1 |
Turns alarm on if phone line is in use. |
2.91 |
993 |
| Telephone line guardian v2 |
Turns on alarm if phone line is in use. |
2.92 |
812 |
