Ford Probe Audio Amplifier Modding *USB LCD / winamp visual*

View the updated project log on my personal site, XodusTech.com

So one of my friends gave me a box or boxes of old goodies, or toys as I like to call it all. In it I found an old Ford Probe Audio Amplifier. First thing that comes to mind is "does it even work?". So it was time to find the pinout tables or at least the wiring guide for the device. After my friend found the diagram I was less than impressed. Not only did the wires for the plugs I had not match the ones on the diagram, but the numbers on the pins on the two black connectors it had didnt even come close to matching up.

So using a little modder's intuition I was able to figure out the power imput lines. It was quite obvious since they were ran to a rectifier type coil to cut out alternator whine (or electrical hum from the power system). But that was not every bit of info I needed to even turn it on. Anyone who has installed an amp in their car will remember the "amp on" line that triggers the unit to turn on. Since in most cases thick wire is run to the Battery+ and ground lines it is far easier to turn it on with another line to provide power. I figured that would be close to the power input, turns out I was right on that.

Since it would not be going in a car or in that type of enviroment again I just soldered the "amp on" line directly to the +12v input. I could change that later to actually be used, but for now its of no issue. Next I had to guess and check mostly for 8 wires on either connector for the 4 speaker outputs and the 4 audio inputs. A little voltmetering and an hour or so later I had all the info I needed. Desoldering the silly plugs it had so I can put my own more useful headers on it.

Here is what I have thus far:

Those were the connectors previously on the board to interface it to the car


The board with its new wires soldered on and the 4 speaker header I saved from an old audio amp that got fried


the speaker header and the 4 rca bolt on plugs I got from radioshack


And the unit all hooked up to the little 12v battery I had handy


I used wire from an old ATX connector to hook it all up, I simply must say its on my list of favorite wire to use. I guess now I need to work on how the power input is going to work, this device was designed for a strict DC setup so most ac based adaptors are going to cause electrical hum in the device. Maybe I can figure out a way to even that out.

Would love to hear any input or comments!

 

Pretty sweet. I've been a car audio installer for 10 years. I've seen lots of those little amps. I take it your planning on using this in your computer.
http://www.wikihow.com/Convert-a-Computer-ATX-Power-Supply-to-a-Lab-Power-Supply
I've done this and been able to run amps much larger than yours. I didn't get any ac hum either because your source, sound card, shares the same ground.
Let me know if I'm on the same idea.
G-luck.

 

Yes, I am planning on using an old shuttle power supply as my dc source for this project, though I am not sure if I actually want to put it inside my computer (no room, its a shuttle), if it would fit in my media pc that is where I would put it. I forgot to mention it but I was thinking of making it power the audio in my dorm. I am actually quite impressed by this little amp and how clear it sounds. I dont like buying things, so building it was the solution I was looking for. So far this project has cost me 2.99USD in the little rca plugs. But in all honesty I could have used some I desoldered off other devices. I just liked these most for this project.

Good find on the converting an old psu to a bench power unit, I am sure other bit-tech'ers might find that quite useful. I have another solution myself which seems to work okay for when I need it. I just like this little amp because it has 4 distinct channels with no mixing or interferance, I have been itching to get 4 channel setup for rear and front for gaming so this may be the perfect unit.

My old amp which is only 2 channel is about 15 years old, and although I really like it. It is becomming to be a bit dated.

 

freaking sweet dude, im glad you got some use outta my old crap, glad to see the probe parts live on i probly missed it but do you know what kinda case you are gonna put it in? you should put it in an old head unit case and make like a volume knob and uv meters and ****

 

Deciding to proceed with this little mod of mine, which is quickly taking longer than I thought it would be. Actually decding to give this a good chance at looking decent. Basically Utilizing some of the old parts to its case to make the new case and to measure up the new parts I will cut. The two large heatsink side peices will stay just how they are, I want this to be passively cooled so it creates no noise, also it gives it that neat look that the sides would otherwise look a bit too bare.

Also making the choice to have all the plugs on the back, one thing I cannot stand is for plugs to go in more than one end of a device. So the back will have the speaker outputs, the audio inputs, and the power input. For this particular device I will make it externally powered. This is for two reasons. 1) To attempt to cut down on any electrical noise that would interfere with good audio 2) To keep the unit I have to look at much smaller and the power brick can be somewhere else. It also gives me several options for powering it as it takes a very standard 12v input

Enough talk right? on with the pictures you say? okay

Pictures:

Just some pictures of the current amp board, as well where I have marked on the white heat shrink which audio input line goes with what speaker output. The audio jacks are also labled on the wire. For my own benifit


Some parts of the original case, the two large side heatsinks, and one of the front/back peices that I am using to hold it together and to make new ones


The case taking shape and one of the top plates that were originally on there, Not sure if I will end up using it either.


Sliding in the amp board into the heatsink case assembly


This shows the speaker output assembly, which will require me to cut away part of the amp board and relocate a few componets and traces to fit inside the case. It is either this or make the case much larger and fuglier. I choose the solder a little bit route.


This is the little bolt on barrel jack that I will be using, it is from radioshack. I Use this size of barrel plug all over. I have many devices that use 12v and this size jack. My way of making things more modular.


Just a shot of the audio jacks, and the front/back peice of the amp, showing how thin and small it is.


My plans for the front will probably involve a power switch, a power led perhaps. I would like to either have a vu meter, or led's to show the music levels for each channel. But that will probably not happen. I will most likely keep it basic.

I would love to hear any input on this!

 

Small update, Decided to go ahead and cut out the spot on the amp's board and relocate the componet that was originally in that spot

Pictures:

Image showing the speaker header now in the same spot where i cut the spot out on the pcb and the capacitor i relocated


More pictures of the same, more angles of the cutout and how it will fit in there now without having to make the case much bigger.


I would love any input

 

brave man cutting the pcb, what all did you have to relocate? any noise associated with the move? other than that looks good, how does that connector mounted though? is it above surface mount or under?

 

The actual speaker header will be mounted to the new back metal plate I will have to construct, It has screw holes on either side for that. I just needed to cut room in the pcb for it to fit where I wanted it to go. The only componet I moved was one of the capacitors used to reduce noise on the input (probably also to bring its power levels down so it wont damange the amp chips).

No noise from what I can tell. Everything seems to operate just exactly how it did before. Also I didnt have to fear too much with cutting into this pcb, I knew it would be a single layer since A) its old, and B) i shined a bright light and could see no other traces through the pcb

 

Wow. I find it funny to see someone put this much effort into a ford amp but it looks like it's turning out great. Do you plan on having it outside your tower case or in a drive bay?
Last night i needed a 12v source and found that a SNES powersuply is 12V at 3.5 amps. Something like that would be good enough for you amp. I think.

 

For now I am just using a flex atx powersupply to drive it. Just about anything with low noise and decent amps will do. Even though it is a little bit of effort I always like the idea of reusing things instead of just tossing them out. Also I am quite surprised with how this little amp sounds for its size and free-ness. Also my speakers are decent so it sounds real nice on them.

It is just a fun project really.

 

Something odders might buy is a RC car 12 volt switching power supply.

 

Time for another update, I have decided out of the interest of being somewhat bored to go ahead and cut up a mockup back plate using one of the plates that were originally on the unit, If it were not for the gaping hole in the middle of it I would be inclined to keep the plate as is. But since I am getting good metal for this project I decided to mess up all I wanted to on the original peice and get all the measurements right for a new cut on the final peices.

'nuff talk, more pics:

Some rough first cuts with the dremel, and then the connector finally in the hole


Pic showing the reason I had to cut part of the pcb, and the header mounted with screws


The little bolt on rca jacks and the pilot holes for them


RCA jacks all mounted and soldered up


The unit all completed in mockup form, minus the power plug since there is no room to mount it due to the ... gaping hole


The amp all pluged in and playing my music YAY


I would love to hear any input. If anyone has good ideas for what I should put on the front of the unit!

 

put a uv meter out of your old amp in that hole looks really good dude

 

dude frikken pwn, yeah def a uv meter.

does it get warm? you could use it to keep your toast from getting cold.

 

Small update, I soldered up the DC jack I will be using in this project, as well I have made a power cord for it. Just thinking on what I want to do with the front of the little amp.

Pictures:

Shots of the dc jack, just kind of held in place until I get new metal plates


A spot I have picked out for my amp right on top my shuttle. Perfect eye level for....


What I want to do is mount a small 2x16 character lcd I have inside the amp to display various information, primarily song info, but could be used to display system stats and other such info. Trying to find a good way to drive it via usb, looking at the thread for making a pic based driver seems a bit complicated. Will investigate further


I would love to hear any input on what I should do with the front, or comments, thanks guys

 

Heh, nobody replied but whatever update:
I went ahead and cut a hole for the little character lcd to fit through. Just for now its held in with a bit of tape, I have some metal standoffs and screws I will probably use to bolt it on there more permanetly. It is hooked up via parallel for the time being. Looking for a good solution to interface it with USB. Perhaps I will do ch424's PIC controller.

Pictures:

Using a peice of scrap sheet metal I made a mockup front piece to cut on


With the new peice bolted in place I sized up for a small lcd


I then cut a rough spot for it to poke through, and brought it to life


Just two action shots of the lcd on and the amp all bolted together


I think it looks pretty slick with the lcd in there, I can display winamp info on it while I use it to play my music The lcd also has a backlight which will be easily usable. If I can get the usb interface going I can draw 5v directly from usb. Otherwise I will have to devise some way to power that. 7805 regulator if it comes to that.

 

looking good dude, too bad you dont have an LPT port in the shuttle

 

Small update, was thinking it may be nice to have a swtich to turn the unit on and off. So since it is still in the mockup phase I went ahead and cut a small hole for the power toggle to poke through.

Pictures:


I may end up having to cut away more parts of the amp pcb to fit the lcd properly for the final product, relocating 4 or 5 traces. Not so terrible, sometimes you have to hack things up to get it to look right anyway

Anyones thought on the power switch. I am on the fence about it, I like the way it looks with just the lcd, very minimal, though I do like the ability to turn it on or off.

 

Looks Sweet. Cant say ive ever seen a car amp used in a pc, but its a sweet idea. I like the lcd and the powerswitch on the front looks fine imo. Nice work!

 

Looking good - it's a nice case!

I love aluminium.