Remote turn on lead ?

[BDiggity]

Here is one for you Christian. [smilie=crazy]

Alpine pdx in berth will have 2 input sources controlled by an input selector; one from alpine receiver, other from dvd player. Easy enough. But now i am trying to figure out how to have the amp turn on via dvd player, w/out having to turn on the alpine, which eventually would turn on all other amps, which may not be needed.

I was thinking about splitting power off the dvd player & send to a relay. Have the alpine connected to the same relay. Then whenever the relay gets a signal (from alpine, dvd, or both) it then sends signal to the amp. Would this work?

[BDM]

I would wire in a separate switch, just for that amp, and mount it above your input selector. Then you could turn just that amp on, when you select that input source.

[Christian]

Relay and diode the remote lines from the respective units to not back feed voltage to them

[BDM]

You really wouldn't need the relay though, if you diode the lines from each power source. You'd just hook both remote turn on lines to the input on the amp.

[BDiggity]

You really wouldn't need the relay though, if you diode the lines from each power source. You'd just hook both remote turn on lines to the input on the amp.

Well eventually i would like to add 5 more amps, so i think a relay would be needed to power on all the amps. Might as well wire it up for long term use the first time.

Dont most auto relays already have diodes in the circuit? Could i use one of those? I know its 12v, but how many amps? Cant be very many.

[joey]

You guys are KIDDING me, right. :confused:

[BDiggity]

You guys are KIDDING me, right. :confused:

about?

[Christian]

No the diode goes between the turn on lead from the HU / DVD to the relay so you don't backfeed voltage into the other source unit.

You always should use a relay IMHO to turn on amps / accessories it just provides a lot more amperage to the amps to ensure good reliable turn on even with volatge fluctuations from the turn on lead from the source unit [smilie=042.gif]

[Christian]

You guys are KIDDING me, right. :confused:

which part is kidding?

[BDiggity]

So Christian, like this?

I am not sure if my relay schematic is right. Been a long time since i have had to know any of this stuff.

I would have to throw a meter on the Valor to see when that 12v output initiates. The manual doesnt say what it is for, im guessing maybe to run small lcd tv. But i think i could use that as a remote lead.

[Christian]

Looks right, you will wire it like this

30 goes to the 12v from the battery
85 goes to ground
86 goes to the input to trigger the relay
87 goes to the amp
87a does nothing

[BDM]

Well eventually i would like to add 5 more amps, so i think a relay would be needed to power on all the amps. Might as well wire it up for long term use the first time.

Dont most auto relays already have diodes in the circuit? Could i use one of those? I know its 12v, but how many amps? Cant be very many.

Unless you're routing the actual power wires (which I'm pretty sure you're not) through the relay, the relay isn't necessary. The remote turn on lead doesn't pull any amperage. It's simply a "Oh, I got 12 volts there?! Ok, I'll turn on now" lead. It makes no difference how many amps you hook up to it, as they don't pull enough amperage to matter.

But hey, if you want to do it that way, go for it! In some regard, it's probably slightly safer for the head unit, but I still think it's negligible at best. Although the cost of a relay isn't much in comparison to another head unit either... Could be argued either way. :)

EDIT:

Ok, I stand corrected... : http://www.caraudiohelp.com/newsletter/multiple_amplifiers.htm

Seems that each amp will pull about 125MA, and the head units are only capable of supplying 500MA... so you'll need a relay. :oops:

[Christian]

[smilie=042.gif] :mrgreen:

[mnfastboat]

now that was a sweet link for us non understanding people :)
Someday I want to upgrade my system, so I tend to read what others are or have done.
Thank you :)