Hi all i have not posted here in a while due to bad health and other things. My question could have been answered some where else. But here goes i have just bought two red flashing led's that i wish to use on a model train layout, i intend to drive them with a 9v battery. Now do i connect them is parallel or series so as not to drain the battery to quickly.

 

Flashing leds have a built in circuit, so connect them in parallel across the battery.

 

Supplier has suggested using 390Ω in series with some red flashing LED's operating at 18 mA, so may be best for each LED to have own R.

 

LEDs, 555s, Flashers, and Light Chasers