This is a prototype ATTiny MCU to delay power, bias and TX relais by a few ms to avoid SWR spikes with high power on a TLT design PA. I used it also to check the limits of the JLPCB how small and close it works for them. it is just added to another board order to fool around and have a tiny arduino board optocoupled and 12V is flexible at hand. Inspired by eb104.ru to download the arduino code any arduino is needed in ICP mode, see https://bit.ly/2AM6XAZ The BIAS output can drive 2A, 25W if a BD238 is used.