Dunno If I'm the only one but when I tapped off the factory remote turn on wire from the radio ( factory amp still in place for HFL) I noticed that I only get 2.53 volts.

Of course that 2.53v wont turn on my aftermarket amps. I designed a small circuit and would like opinions on it.

Specs on the transistor can be found here. http://www.nteinc.com/specs/2300to2399/pdf/nte2302.pdf

 

I used the 12v switched power wire that runs into the Nav unit in the trunk for my amp. It works great.

 

Just take your circuit and run a simulation with PSPICE or TopSPICE or something similar. When you model the voltage input (i.e. the "output" of the remote wire) make sure you put the appropriate impedance in there.

 

The plot thickens.

I wasnt getting the expected result when I tried to a few minutes ago. With the aftermarket ams hooked up , I am dropping all my voltage.

Wire tapped. 12 + volts
Wire tapped with aftermarket amps attached 2.53 volts

When I attach my amps the stock amp tuns off. Im assuming this is from too much of a voltage drop.

So, it sounds like I have a low current issue? Not enough amperage to power all the devices attached?

I'm assuming I also fried the transistor, as the max vbe is 1.5 volts and I let it have like 4 volts (I was assuming my 'base' voltage was 2.53 as measured with the aftmk amp attached).

Now I'm stumped


I tried a basic 12v relay, but the same thing happens, not enough current to power a relay.

 

That's pretty weird dude. All of the remote-on inputs for your aftermarket (and stock) amps should be high impedance and so the current draw should be negligible (and subsequently the voltage drop should also be negligible).

But, this is what I'm envisioning for you. They sell "power amplifier" chips in 8- and 16-pin configurations that run 12 volts. Use the power amplifier chip to drive all of your remote-on inputs. May want to put a TTL buffer chip before the power amplifier chip that has trigger level below 2.5 volts.

Err, i hope that made some sense. :P

 

Well I give up. Tried rebuilding the circuit with 2.2k and 150 ohm resistors effectively dropping the voltage from 13v to .5v . That didnt seem to activate the transistor (not sure why).

So I tapped off a black wire under the driver side rear seat, that goes into the floor through a rubber seal. Could be a fuel pump wire ?? Any ideas? Gonna post a new thread asking for help.


Kyle

 

KC...I'm wanting to do the same on mine...can you offer any advice?