CheaperRFID via MQTT

[Pete]

ahh...

Understood Michael.

It is suggested over time not to use maximum power on these devices and to tweak them down to minimum required dBs. There is only a setting for the dbs but no way to measure signal strength.

[Michael McSharry]

I finally got around to trying the E32-DTU and it worked good over the 100 ft range I tried. Makes for a nice virtual wire. Since it is 433 Mhz it does not fit into the scheme with any of my other 910 MHz LoRa devices. It would be a small effort to put a microcontroller (e.g. Sonoff) transmitting a fixed pattern periodically via RS322 and then something listening at the other end looking for missing data. Likely easier, however, to just use a ESP32/Lora from Heltec or TTGO to accomplish the same function if that is the objective. It should work bettre than the el-cheapo 433 Mhz generic RF devices I had been playing with for Cheapest RFID.

I have a RAK LoRa device I picked up a long time ago. It seemed more difficult to interface using the tools I am familiar, but may give it another shot this Fall.

[Pete]

Thank you Michael.

Went to using the Ebyte modem with a BetaBrite sign; well testing it with a HS3 user in ATL. A bit overpowered and it should work from the comm closet in the home to the other side of the house.

I have not purchased your parts list yet.

[Timon]

What I've been looking for are tags for my dogs so I can control entry and exit through the dog door. The main issue is you don't want to door to open until they are very close to it but at the same time handle bot tall and short dogs.

[Michael McSharry]

Timon, put a microwave radar sensor at your dog door. There are version where you can adjust range. It is also be possible to use aluminum foil to limit field of view. This, however, is indiscriminate for which animal is given entrance.

Another concept is the tag they put on merchandise to prevent theft. Put an doggy archway around the door with the detector. This would be even more DIY.

RSSI-based devices such as Active RFID, BLE or WiFi have a chance of working, but RSSI is not very precise. Depends upon the proximity resolution you desire. You may be able to reduce the antenna gain so it will only pick up RF that is sufficiently close to satisfy your needs. Prehaps even no antenna on the transmitter will still give sufficient signal for close range. Working in RF is hit and miss without the proper (and expensive) test equipment.

[Timon]

Currently it’s a magmatic sensor so you can’t tell which dog it is.

I’ve looked at RFID but receivers are quite expensive.

I thought about ripping one of the larger door flap ones I’ve seen at PetSmart but my door is much larger and I’d need to come up with a larger antenna.

There used to to be a commercial alerting bot by the same manufacture that makes dog doors but they not been maid for several years.

I’ll keep looking.