Hi, carl47
Finally I found some correspondence related to your fantastic project Ultrasonic Anemometer.
For almost over an half year I am strucling with a not working system.
I built the ultrasonic anemometer on a proto type PCB.
I used the sensor from Conrad a europeean supplier.
Type A-18p20 fabr. EKULIT to my opinion they must work and/or are near the specs.
TR SPL dB >106
RC SEN >-74
Dir deg. 80+/-15
Capa. 1800+/-20%
Allow. inp. volt 140
The problems i found are
The system looks working but not relaiable and or recognized.
It respond on disturbing the beam.
Digital looks to work I hear sound from the sensors all 4 of them.
The value for the envolope is about 8000 not the 4000 which must be.
I use diodes 1N4937 the 1N918 are not avalable. equivalent 1N4148 shoult not work either as written by
Zenon.
The sensor wire I also screened and put to earth (-) you never know.
Do you have a clou what is faulty?
I do realize the info is poor but I cab answer your questions.
Like to hear from you.
Kind regards,
THeo ( ilioSS)