This is a small adapter board to use an HC-05 or HC-06 bluetooth serial adapter for rig control of a Yaesu FT-817. SJ1 is used to provide V+ to the adapter to enable AT command mode on an HC-05. R1-R3 are identical values, and are used to convert the 5v TTL signal from the 817 to the 3.3v signal expected by the bluetooth adapter. R4 is the current limiting resistor for using an HC-06, R5 is the current limiting resistor for the status LED for an HC-05. R4/R5 may be omited if you do not desire having a status LED. The voltage regulator is a AMS1117-3.3v or LM1117 3.3v regulator. This board is designed to be able to be left on the radio, even when it is standing on the back end, and not interfere with any other ports.

Please note that the FT-817 leaves the port powered at all times, so it may be advisable to leave the LED off if concerned about power consumption. The bluetooth adapter itself is rated to consume 10mA while actively paired, and 30mA while disconnected, according to the datasheets I have seen.

EDIT 7/24/26: V2 of this board has been created due to some issues of an unconnected ground. Pads for a capacitor have also been added. V2 can be found here: https://oshpark.com/projects/eAvOHn82