Relay Bypass Board running on 18v supply

[Many__Of__Horror]

I am looking to run an overdrive circuit with a relay board at 18v. The circuit is fine as I have enough in the caps and the IC ratings.
I just wanted to sanity check my understanding of the relay board. Looks like the voltage runs straight into D1 as a protection diode then into the L78L05 voltage regulator. My look at the datasheet leads me to believe that the L78L05 will have no problem accepting up to 30v?

So C1 being a box cap which usually have a minimum rating of 50V and the L78L05 nothing else should get the 18V supply?

1N5817 appears to have peak voltage of 20v, is it better to go to a 1N5818/9 or it should be fine?

 

[Robert]

1N5817 should be fine if that's what you have but if you're ordering parts you might as well go up to 1N5819.

C1 and D2 (and of course IC1) are the only components that should be exposed to 18V. Q1 will see whatever voltage powers your LED, but 2N3904 can handle 18V.

 

[Many__Of__Horror]

Thank you, had forgotten about incoming from SW pad