Not sure I understand the problem fully, but you want a circuit to operate when you push the horn button, without affecting the horn operation.

Chances are the relay coil is drawing to much power.

Have you thought about adding a transistor to your circuit? It would draw very little current from the horn circuit but should allow you to drive something else. - such as your relay. It would of course require you to do some electronics.

Remember that you are also interviewing them. They won’t expect you to know all the answers, but will want someone that they can work with. If you can, answer questions with the STAR method (situation, task, approach, result), but don’t waffle. You can use one piece of experience in a variety of ways: teamwork, research, urgent deadline etc.

It’s ok to say that you are nervous, they should try to put you at ease.

You may be asked ‘trick questions’, these are not usually to to you up but to see how you work an unknown problem. There is no right answer. Not knowing stuff is ok. Not being able to think up a plan is less so.

Remember whatever the outcome, this is really useful experience. See if you can get a site tour, ask about the tech used… You can then add this to your knowledge for later. In my experience, industry is frequently several years ahead of academia so you get a good chance to understand the real world.

Ermmm… If you use several pins to get the current rating, what happens if one of the pins fails or gets corroded? Won’t you risk generating heat? Think I’d prefer nice big connectors for the power and to keep the data lines safely segregated. Depends on your needs and design I suppose.

Brilliant, many thanks. With all the old phones in my cupboards I’d hoped this was the answer, but it’s good to get a second opinion.

Butt your enclosure right up against the lock body, then you reduce shearing forces trying to pull it off the door. Extend the pull bar through your enclosure so you still have a manual override.

While I’m not adverse to home automation, is this something you need in your life, or just want? I like my perimeter security too be simple and tight, extra complications make the security audit much harder.

Will your insurance stand up to home made remote control unlocking?

To answer your question, place the servo in a suitably large enclosure and practically any adhesive should work, e.g. 3mM command strips or even velcro or double sided sticky. When confident that this is what you want, use a screw.

Yes prime minister is the most accurate documentary about British politics of all time.

Do you on now anyone who uses disposable vapes? There may be a useful battery in one of those if you can’t find an alternative.

Arduino and esp32 are both good places to start. On YouTube look up ralph s bacon I think he is - He does lots of microcontroller stuff, and of course the likes of big clive will teach you all about basic electronic circuits.

If you’re a complete newbie, get a kit and work through the tutorials.

Stuff you’ll need at first is a microcontroller, prototyping breadboard and a few components (should all come in the kit of you go that route). When you have something that works that you want to keep, you can think about a cheap (ish) soldering station and either veroboard, or look into getting your own boards made.

A multimeter will help a lot (cheapish will do) and depending on how deep you get, a bench power supply and an oscilloscope, but you can live without those for a while.

Get good quality solder, and using extra food quality flux changed the game for me. If you are an older person, magnification really helps too!

Get components in 10’s or more as you’ll save a little and it doesn’t matter much if you let out the magic smoke. For hobby stuff, Alix is your friend.

Have fun.