This is just one of those FYI posts along the lines of hmmm...that's interesting.
I recently went through the effort of decoding RF signals from the AcuRite 00606TX sensor. The data includes some very odd message check bits, which are included to verify that none of the data was garbled during transmission. Most consumer-grade sensors use either a simple "check sum" or a more robust "CRC" technique to generate check bits. The 00606TX uses neither of these techniques.
To make the long story short, it turns out that the 00606TX check bits are comptued using a technique which is nearly identical to that used by the Ambient Weather F007TH sensor.
The method of computing check bits is so unusual in the world of consumer-grade weather sensors that I think there is little doubt that the same folks are somehow behind both sensors. Whether AcuRite and Ambient are getting these from the same lower-level supplier or whether the two companies are partnering on these things I cannot guess...but there's not much doubt that the AcuRite 00606TX and Ambient F007TH sensors have a lot in common. I've been wrong before and I'll be wrong again, but the coincidence here is rather striking.
To add a little icing on the cake, the circuits on the transmitter PC boards are also nearly identical and use the same two transistors.
