I'm afraid you won't get "beacon" like board with battery power circuit and holder below 10 USD (at this quantity) but still overall cost is unbeatable with other RF equipment.
Right, not with battery holder. There are extremely cheap WT51822-S4AT modules, but soldering battery holder would be necessary for them. They work just fine for me though.
Can you post a link to your supplier of those modules at that price.
I have some of them, but they cost 2 or 3 times as much as you paid.
BTW. not that it matters for this application, but they dont have the 32khz crystal, so some code changes may need to be made to the beacon example to use them.
Yes Roger - for precision timing applications they are not so good. but for beacon purpose they seems to be ok. I bought some of them here. It is QFAA, sadly :/ Cannot find QFAC anywhere.
