On Thu, 14 Jul 2016 13:29:38 -0400, Bob Engelhardt wrote:

On 7/14/2016 11:40 AM, Cursitor Doom wrote:
... But the 555 board's resistance is
about 22k ohms so it only needs a very small current. ...

Can you measure what the board is actually drawing?

When connected to an external bench power supply at 12V., the board draws
9.3mA. The bench PSU doesn't have any issues powering this board.

When connected to PSU that uses the LM317, however, it draws 3mA and the
voltage across it drops to around 6V.