Trying to build a circuit or 2... HELP!

**ddt** · 02-25-2003, 03:04 AM

Guys... I'm building an auto startup circuit as per Spuds design here.

I hope it works... anyways. I need to figure out 3 things.

1) Which is the positive side of the cap and which is the negative? One side has a long lead and the other shorter. Other than that not many lables.

2) Resistors... Can you put them in any way? Or is there a right way and a wrong way (as far as orientation)?

3) The NPN Transistor... another orientation question. Which side goes towards the ground? The collector or the emitter? And does the base get connected to the 10K resistor?

As you can probably tell I don't read circuit diagrams well and the only circuits I've built were definatlry of the paint by number variety.

Okay second question. I would like to build a relay that would take the extention of my ACC line that runs to the amps and have it cause them to wait a variable amount of time (like user defined like on Maestero/Jeff's shutdown controller) after I start the engine so that I can have them turn on a set time after I start the engine. With the auto startup circuit, my computer should be booting by that time and that way I will not get that annoying loud pop from the speakers when I boot the PC. I mean.. it's anoying and it can't be good for the speakers.

At least that's the theory. Let me know what you guys think.

**t0ffluss** · 02-25-2003, 04:09 AM

hmm.. i dont know much about those diagrams questions.. but, the thing i did for the loud anoying pop sound when the pc were booting, were just to have the 12V from the OPUS, connected to the remotes of the AMPS, no more poping sound, cuz the amps are a bit slower than the PC. The only downside, is that the music keeps playing for 5 sec after the car is switched of..

Richard

the transistor thingy, the BASE .. i think, is allways the pin in the middle, was it a NPN transistor? .. if so, i dont think it would matter either way you but it.. dont know for sure tho..

good luck

meastro, or all the other electronic guru's are sure to help you in a while

**Rob Withey** · 02-25-2003, 04:15 AM

Originally posted by ddt

1) Which is the positive side of the cap and which is the negative? One side has a long lead and the other shorter. Other than that not many lables.

2) Resistors... Can you put them in any way? Or is there a right way and a wrong way (as far as orientation)?

3) The NPN Transistor... another orientation question. Which side goes towards the ground? The collector or the emitter? And does the base get connected to the 10K resistor?

1) If it's an electrolytic, the negative side is usually indicated by a stripe on the case.

2) Resistors are not polarised, they can go in either way.

3) For bipolar transistors (either NPN or PNP), the emitter is the one with the small arrow, so in this case gets connected to ground. The base is the one connected to the 10k resistor. Collector goes to the 1k resistor.

HTH

Rob

**Aaron Cake** · 02-25-2003, 09:21 AM

Please ignore t0ffluss.

1) Which is the positive side of the cap and which is the negative? One side has a long lead and the other shorter. Other than that not many lables.

The side with the stripe on it is negative.

2) Resistors... Can you put them in any way? Or is there a right way and a wrong way (as far as orientation)?

Any orientation is fine.

3) The NPN Transistor... another orientation question. Which side goes towards the ground? The collector or the emitter? And does the base get connected to the 10K resistor?

The base connects to the 10K resistor. Emittor to ground. Collector to the juncton of the 1K resistor and 100uF capacitor.

Check out http://www.aaroncake.net/electronics/schem.htm

**mp3hombre** · 02-25-2003, 11:23 AM

3) The NPN Transistor... another orientation question. Which side goes towards the ground? The collector or the emitter? And does the base get connected to the 10K resistor?

Transistors Pinouts here

Okay second question. I would like to build a relay that would take the extention of my ACC line that runs to the amps and have it cause them to wait a variable amount of time (like user defined like on Maestero/Jeff's shutdown controller) ...

Do a search on google for a "555 timer".

**ddt** · 02-25-2003, 02:24 PM

Thank you all for your helping the "electronically challenged"... and IT WORKS!!! sort of.

BTW Aaron... that's the most comprehensive (and easy to understand) schematic symbol reference page I've seen so far. Thanks!

**ddt** · 02-25-2003, 02:57 PM

Okay, I'm "electronics construction dumb" and "circuit building challenged" and you want me to design a 555 timer for my app? I think I could build it, but design one? Rrrr... There has to be something pre made.

**mp3hombre** · 02-25-2003, 04:40 PM

Originally posted by ddt
Okay, I'm "electronics construction dumb" and "circuit building challenged" and you want me to design a 555 timer for my app? I think I could build it, but design one? Rrrr... There has to be something pre made.

This might help