Thread: I ditched the 2140 & made my own SSC...

I haven't done much posting here, mainly reading. But I figured I would share my little project I've been working on.

A little disclaimer before I begin my rant about the Carnetix 2140. I've installed car audio professionally from 1994-2005. I've installed for a variety of businesses. Ive worked at Eagle Distributors, Mobile One Autosound, Best Buy, Circuit City and Car Toys over the years. So I know a little about what I'm doing.

If you have a Carnetix product (1900, 2140 etc) and you like it, it is working great for you, that is fantastic. Stick with what works best for you. Everyone has a different setup, system and situation.

I originally bought the 2140 to run my laptop but more recently I had the 2140 unit running an mini ITX machine. Ive always had one problem or another with the 2140.

The DLYON output is a weak beotch
I hooked up two small Alpine amplifiers and one MTX amplified Thunderform to the DLYON output. It wasn't able to turn on 3 amplifiers. Amp turn on inputs take mere milliamps to activate the amplifier, wtf? So I figured I would use a simple SPDT relay and maybe the 2140 would do it then. WRONG! The relays I use require about 100 milliamps to activate them. I only had one relay hooked to the DLYON output and guess what? It fried the DLYON output. Again, WTF? So I ended up getting the unit swapped out (Thank you MP3car.com!) and bought a PAC TR-7 to get the new DLYON to work. In my professional experienced opinion, the DLYON output needs to be re-designed.

So it cost me an extra $15 (for the TR-7) on top of the price of the 2140 just to turn on my amps. Pretty much any headunit with a remote out can activate 3 amps (my Alpine did it no problem, same three amps too). I have never had a problem ever with a remote out not being able to turn on three amps or even activate a relay. I assumed since the 2140 DLYON was designed to turn on amplifiers that it would behave just like a head unit remote out. Thats what happens when you assume, lol.

The 2140 could not consistently keep my machine in standby.
About every 4th or 5th time I started my car, the machine would start from a cold boot. I set the thing to standby and it would work only about 80% of the time.

I installed a dedicated battery, a Kinetik HC800, thinking voltage might be getting too low. I never had a problem starting the car, but what the heck, lol. When the ignition goes off, it disconnects the carPC battery from the main battery. So the PC can standby as long as it needs to and wont affect starting the car. This didnt help and the problem still prevailed. I ended up temporarily installing an Autometer Phantom series volt meter I had laying around and ran two long wires back to second battery. That way I could look at the voltage the 2140 was seeing before I start the car and the charging system takes over. The lowest voltage I ever saw was about 11.5 volts and that was even after the car sit all weekend without me driving it. Keep in mind also that in the psumoni application I set the shut down voltage on the 2140 to 10 volts.

Maybe it was heat related. I live in Houston and its hot here. But the weird thing is. These symptoms would occur at night and early in the mornings when it wasnt even that hot out. I work night shifts, four nights a week, I would get to work at 7pm. Shut off the car, come back at 10pm to go to lunch. The PC comes out of standby just fine. I get back from lunch. The PC goes into standby. I come out to the car at 5am to go home and I get a cold boot. Wtf? You know what you get when you cross an elephant with a rhinocerous? L-F-I-NO

It could have been heat due to the 2140 having to keep the PC energized during standby. But come on, there isnt that much current required to keep a PC in standby. I figured if powering the unit during standby was causing heat shut off, then why wouldnt that happen when the PC was on? It takes a lot more current to run it than have it in standby.

I gave up. Maybe it was some error on my part, but I couldnt stand it anymore and started looking for something different to handle what I purchased the 2140 to do.

Three PAC TR-7's, three SPDT relays and two 120 watt mini-ITX power supplies
Im sure there are lots of other neat (and cheaper) ways to solve this problem. But I have a lot of relays and wiring laying around from my car audio days. I like these kinds of projects because it lets my flex my car audio muscle. I picked up a couple more TR-7's and got to planning.

So here is what Ive got.

TR-7 #1
Handles the remote turn on for the amps. Feature #12 (delayed on) in TR-7 instructions. I programmed it to turn on the amps 20 seconds after the ignition comes on. This gives the machine time to come out of standby before turning on the amps which eliminates turn on thump that would occur when the sound card initializes. (this can be easily adjusted from 1 second to over 4 minutes)

TR-7 #2
Handles turning the PC on and off. Hooks into the power button on the PC. Ignition comes on, sends a pulse to a relay that "presses" the power button. Ignition goes off, sends another pulse to turn it off. Using feature #9 (door lock pulse generator). The TR-7 thinks it is locking the doors when the key is on and unlocking the doors when the key is off. We wont tell it otherwise.

TR-7 #3
Not really needed but Im using this one to keep the monitor on for 30 seconds after the ignition turns off. I like to see the screen showing that Windows is standing by so I can see as Im getting out of the car if there is any problems. This isnt really necessary but I had an extra TR-7 and found a use for it, lol. (this can also be adjusted from 1 second to over 4 minutes)

The relays
One is used to "press" the power button so the machine goes in and out of standby.
One is used to turn on a secondary mini-ITX 120 watt power supply
One is used to turn on the amplifiers

Two mini-ITX power supplies
The mini-ITX case I bought came with a 60 watt power supply. Pretty weak but it never was a problem. But recently I found these 120 watt power supplies for $18.99. I bought two of them. I used one of them to replace the 60 watt unit that came with my mini-ITX case. And the other one I used to power my screen and extra USB peripherals up front (extra hub and a slot load DVD-R).

Now my screen has its own dedicated 12 volt rail and the slot load DVD-R and USB hub have their own dedicated 5 volt rail. So the power supply running the PC doesn't have to compete for power at all and everyone is happy.

I know this probably seems pretty complicated to wire all this stuff up, but its not as bad as it sounds. This type of setup wouldn't be for everyone but some of you may find it interesting.

Does it work?
Absolutely perfect so far. I will report back if there are any hiccups. The cool thing to me is, I know exactly what is doing what, how it does it, why it does it and when its going to do it. With the Carnetix 2140 I was at the mercy of the person who designed it and if I encountered any problems, I had to beg for support. I don't know if any of you have been on the Carnetix support forums, if you have then you probably know what I think about that.