Still in the design stage of my launch controller. I’ve picked out my box, (A lunchbox sized Pelican Case) it has plenty of room for a cool control console, and a 12 volt lantern battery (but I don’t think that’s the right battery anymore). But then, I get greedy with the feature set. And I think I need the help of an EE. I understand the basic circuit (since I was 12), (battery, key switch, light, momentary contact switch, wire, gator clips, - got it) I can make that. But I do have a couple of questions about component selection: 1. 12VDC 10amp components, right? So like a motorcycle or lawnmower key switch? 2. What’s the *right* wire to use for an E-class controller? (able to handle the voltage, but not too much resistance in 30 feet?) 3. What’s the right battery to use? Again I’m thinking E class, or maybe even clustered launches or multiple pads. But this gets into my feature-creep problem. Which I’ll get to next. So, then I start to think of cool features I could add, but only if they are cheap and easy: A flashing continuity light? A beeping and flashing continuity light? Do I understand if I put this motorcycle turn signal relay: https://www.ebay.com/i/222730589660?chn=ps in the continuity light circuit I’d get beeping and flashing? A countdown LED ?? That would very cool! I’ve been looking at various LED clocks and/or timer kits, like this: https://www.newfrog.com/product/dc1...imer-digital-led-dual-display-0-999-mi-191153 But that’s a relay that can control a device – (like launch the rocket for me – NOT what I want to do), and it has its own little tiny start button, I would prefer something like just a large two-digit ten second countdown that starts when you flip the keyswitch. Could that be easily done by a layman? Or should I just give up on that idea (maybe I’ll put a clock in the corner)? Battery level indicator? How much power would that use? (I see digital voltmeters for like 2 dollars, or is that a different thing?) Now please explain about battery choice and capacity. Like I said, I have room for a lantern battery. I want the capacity for a long day of e class launches, maybe clustered launches. (not that I’m doing that yet, I just want to be able to). I will also be adding the Eggfinder RX unit to the box, so we need to power that. Rechargeable would be nice. What circuitry would be needed for recharging? I don’t want to take it out and put it in a charger. But that has me thinking (and here feature-creep sets in) if I’m carrying a large rechargeable battery out to the middle of a field… my laptop battery sucks, especially if it’s running two webcams at once. Could the Launch Controller power the laptop? (12 VDC Out?) Could I recharge my phone from it? (USB charging out?) How about a small fan, it gets hot out there. So that’s the questions I have that require an EE: How much power do I need for the launcher and eggfinder? How much power can I carry in a lunchbox size container (and for how much money?) And what could I do with that power? (as in accessories like the laptop, I was kidding about the fan) As always, any help appreciated Thanks guys!