This is not a direct answer to your question about the transmit button, but there IS an iPhone transmit button on the BTECH PRO that allows you to communicate all over the US.
1. Open your phone app. (BTECH GMRS PROGRAMMER) you need to be connected to the app via Bluetooth. I thought I was initially, but I wasn't. If you are, you will see the name of your radio IN THE DEVICE list area.
2. To access the device list, while in the map section on your iPhone, on the bottom left, you will see an icon with three lines, click on it.
3. you should now see your radio's name under My Device, radio name, Connected.
4. Once you have accomplished this, click the network channel (your radio name should be available under the network Channel).
5. At the very bottom you will see a blue push-to-talk button.
6. You can now talk all over the USA, literally.
(Note, I am a brand-new user and just now learning how to use the radio. If I made a mistake(s), please let me know and I will update this list.)
Steven Hill, USN RET
