@johnbflat I'm not aware of a cellphone that has a telecoil but it's certainly possible. Old landline phones had the equivalent of a loop transmitter that would send the signal to a hearing aid inductively. However, if your cell phone did have a telecoil, it would have to be a "receiver", as opposed to a "loop transmitter" to work in the scenario that you describe. In your scenario, the venue would not be considered telecoil, but a loop transmitter. Your telecoil equipped cell phone could pick the signal up and Bluetooth it to your hearing aids. Again, I'm not certain of a cellphone that has a telecoil. For hearing aids without a telecoil, that function can be performed by an accessory device that would be obtained from the hearing aid manufacturer. The telecoil would pick up the venue loop signal and send it to the hearing aid, not by Bluetooth, but by the "near field" signal that is proprietary to the hearing aid manufacturer.
Tony in Michigan