| ??? 11/28/07 13:23 Read: times |
#147503 - Similarity to IR remote Responding to: ???'s previous message |
The most readily available ultrasonic transducers have their peak response at 40kHz (due to internal resonances). It's no accident that IR remote controls also use 40 kHz as their carrier frequency, as the early designs were adapted from ultrasonic designs. I would start with the design of an old fashioned IR remote where the modulator and demodulator aren't integral to the optos. |
| Topic | Author | Date |
| Ultrasound Data Link | 01/01/70 00:00 | |
| Not really ultrasonic. | 01/01/70 00:00 | |
| The other issue ... | 01/01/70 00:00 | |
| Echoes | 01/01/70 00:00 | |
| Speed of sound vs. speed of light | 01/01/70 00:00 | |
| multipath | 01/01/70 00:00 | |
| Signal attenuation is very big | 01/01/70 00:00 | |
| Similarity to IR remote | 01/01/70 00:00 | |
| the cheapest ultrasound transceivers ... | 01/01/70 00:00 | |
| Frequency ? | 01/01/70 00:00 | |
| Fish finder freq. | 01/01/70 00:00 | |
| Miniscule | 01/01/70 00:00 | |
| Thanks - that's useful | 01/01/70 00:00 | |
RC5 should do it | 01/01/70 00:00 |