12V Mini PCB Relays Arrive

FINALLY! The mini Songo 12V PCB Relays arrived!! There was a slight shipment issue according to the eBay seller so I waited a much longer time for delivery but luckily the first batch of 10 have arrived so now I can begin work on my Relay board for my Lower Console makeshift Space Matt buttons I had made out of the old calculator. You may remember from an earlier post. I basically want the Space Matt buttons to activate the DTMF tones generated by the Knight Rider World Voice Box. Now given the configuration of how my Space Matt buttons are wired and that I am NOT an electronics expert by ANY means this was the best and easiest solution I could come up with. Now these Songo Relays are very tiny and will more than do the job needed by my Space Matt buttons to activate one Relay for the DTMF tone for each button and also another Relay for any given function I choose.

Now like I say I had worked out a diagram that should do the job needed for my Space Matt buttons. As you can see here the DTMF tone request pulse is isolated from the button device function activation pulse. Someone more electronics savvy may have another option but this was what I came up with given my limited electronics knowledge and the way my Space Matt buttons were configured. The Songo relays are very small so I can get a lot of them into a small space by soldering them onto some Proto Board and wiring them in accordance to my diagram.

Lower Console Make Shift Space Matt Buttons Additional Wiring Scheme

"Not now Michael, I have a headache"

There may be a better way of doing this but this is for now how I figure I am most likely to approach this particular problem. You see my makeshift Space Matt buttons I made using an old Texas Instruments Calculator are wired like this; All of the buttons grounds are connected but each button makes and individual connection to that ground. Now the Voice Box's built in DTMF random tone generator request a tone by making a connection to ground. You may be begging to see the challenge here ;) So what I have done in this diagram is I have mapped out a way of using two sets of SPST Relays connected to each of the Space Matt buttons individual ground connection wires. What happens here is the first relay in the "Yellow" zone is isolated that it makes the ground connection for the V.B. DTMF tone request connection. The second SPST Relay in the "Blue" zone is isolated in that each one can momentarily activate a device. I could complicate this further by introducing "Step Relays" in order to make the momentary button into a latching button but lets not go there ;) Complicated I know but it will get the job done and do what I need it to do.

Alternate Space Matt Buttons Wiring Scheme

I was having some issues trying to work out a way to utilize each of my Space Matt buttons that I had made out of an old Texas Instruments Calculator. The problem was that the V.B. (Voice Box) random DTMF tone generator needs a ground pulse to activate a random tone, but with this type of button configuration where all of the buttons are connected to one wire (in this case ground) and the other buttons individual connections to that ground it was difficult coming up with a way to activate both a device and generate a tone through the V.B. So I came up with this idea. Seen here in my diagram I have two buttons wired to show a way in which they can all be wired in the same way to do just that, activate a device and generate a tone. In my diagram the ground connection through any one chosen Space Matt buttons will activate the relay's magnetic coil causing it's internal switch to close, in this case the needed ground connection from the V.B.'s DTMF tone generator to ground. It's a bit daunting having to use all of those relays but I can't think of another way off hand how to do this. Maybe those small "Songle" I think is the name of them relays would do the trick for this?

Example Image of "Songle" relay.

Testing Out My Calculator Space Matt Buttons

Although I have not gotten all of the wires from my make shift Space Matt Buttons wired into Molex Connectors yet, almost there just need to get some more 22 AWG wire as I ran out yesterday. I figured I would work out a diagram of how the buttons are configured and what I'm proposing to do with them in regards to using them to cycle through the message in the Message Centre and have then produce a random DTMF tone from the built in tone generator in the Knight Rider World Voice Box (V.B.)

Theoretically I'm thinking this should work based on the instructions that came with the Knight Rider dash electronics. As you can see in my diagram I have combined all of the momentary switch button wires into one wire to ground, they do have the option to be used individually in the future as I have wired them up to the Molex connectors separately. But for my immediate purpose right now just a single ground signal from all of the buttons to cycle through the Message Centre and request a random DTMF Tone from the V.B. will do for now. I know from my test yesterday that the Message Centre will cycle through with a simple Momentary switch. My only concern right now is are the V.B. DTMF Tone Generator and the Message Centre momentary switch options wired the same way?? This is something that needs to be figured out.

NOTE: Today I did a Multi Meter test on both the Message Centre Cycle Connections and the V.B. DTMF Tone Request Connections and get a reading of around 3.9 when set to DC Voltage so I think they are set up the same way as far as input signal. 

Installing And Wiring My Space Matt Buttons

"Buttons, Wires and Connectors, Oh My!"

Well I installed my make shift Space Matt buttons a little differently that I wanted too. I was going to cut out my rectangular hole a little bigger so as to sink the Space Matt buttons array into the hole so it would sit flush, but I'm a little hesitant to do that because the hole is cut to the size of the USB Space Matt Keyboard buttons that you can get from Knight Rider World, and like I say these may just be temporary buttons for me to use until I get around to ordering the USB buttons. Of course me doing it this way means that my plastic overlay I made is a little too thick for how I have the Space Matt buttons placed into the console as in they sit a little deeper down. I may make a thinner overlay out of some metal stock I have kicking around, I'll see what ends up looking good.

I had drilled in a large enough hole into the top of the fibreglass console to be able to thread in my wires for all of the buttons. I had to add a little more length to the wires so I would have a little more room to put in my Molex Connectors. I had to get a couple of 15 Pin Connectors as the electronics place did not have anything bigger. That's OK though, it just means having another connector sticking out of the wire loom ;) Each one will be clearly marked so they can't get confused so no biggie.

I have the one wire that connects all of the buttons together on the far side of the Molex Connector and then the 4 rows of individual wires for each button connection using up the remaining pins of the connector. This way I can organize them on the connectors in rows from top to bottom. Here in this picture on the left you can see I have started putting together the wires into the connector, I have the main buttons feed wire in place and the first top row of buttons wires in place, now to complete the connectors by following the same format. ;)

Painting The Space Matt Buttons

I started the first stage of painting my make shift Space Matt buttons. So far I have them primed and painted. Next step will be to add the coloured bars or tabs across the tops of each button rows. Because these are not 100 percent screen accurate buttons I'll be missing 2 rows of buttons but to me that is no big deal for what I'll ever want to use them for at this stage of the game.

I tested out the buttons on top of the actual button contacts and they work good so long as they are lined up correctly so that will be a little bit tricky when I install them into the Lower Console, but I have a plan of attack for that though ;)

Putting The Space Matt Buttons Back Together

"And They Say There Are No More Miracles Left."

Well it took a lot of mucking about and even some pretty delicate filing with my fine Riflers Files to make the button contacts work nice when each of the buttons are pressed, but I persevered and I was able to get a good contact reading with my Multi Meter once I had filed all of the contacts I had made down nice and flat to match the height of the wire laid into the groove in the white plastic bed. Basically I had poked a 22 AWG wire through tiny holes I drilled into the mounting plastic bed that the Brass or Copper buttons sheet are laid over top of. (I can't tell which my guess is Brass). I had then soldered those wires onto the inlaid wires running through the plastic mounting bed. Fiddly work but I got it done.

Next step was to re attach the thin metal Brass button's sheet onto the white plastic mounting bed where I had made my modifications to the existing contacts so as each one can be assigned separately if needed. I did another Multi Meter test to make sure they were making a good contact when pressed and labeled each button wire with my usual green painters tape method. You can see in the image on the right how I like to identify each of the individual buttons.

I suppose now the next stage will be to pull out the lower console from the car and figure out the best way to install my newly configured Calculator buttons array into the console. Good thing I never fully installed it ;) I'll paint my buttons first though after I do any trimming needed to make them fit into the console. So far looking good though.

Space Matt Button Array Idea

OK so in the spirit of trying an experimental idea that I'm sure it far from original, but new for me in any event, I figured I would try and see if I can do an experiment with some buttons from an old Texas Instruments Calculator that I found on eBay. The buttons are pretty close to what is seen in the actual Knight Rider Lower Console Space Matt array. Obviously they will need to be painted and then the coloured rectangles added. But hey I figured for $8.00 on eBay it's well worth the experiment just to have something for now until I eventually get the USB keyboard Space Matt buttons from Knight Rider World.

Not The Droids I'm Looking For

OK so one slight snag already with my Oh so brilliant plan. After I dismantled the Calculator I was a little disappointed to see that the buttons inside were not quite the type I was expecting. I thought for sure they might have been the mini Micro Buttons soldered onto a small circuit board. Instead they turned out to be these very tiny brass or copper ever so slight dome shaped sheet type buttons with a plastic back and a sticky black plastic cover that holds them over thin brass or copper wires running through the white plastic bed for the buttons.

I'm still pretty determined though in that I think I can still make them work for what I intend to do with them, they are after all a crap load of tiny buttons that apart from the USB Keyboard variation I can't REALLY think of too much to do with the Space Matt Buttons array out side of simply hooking them up to a DTMF random Tone Generator.

One of my initial thought is to simply hook up the buttons array to the Message Centre and just simply have the array cycle through the messages with random DTMF Tones. This to me so far would be a very simple use for them.

Wiring Up The Individual Buttons

Now even though I have mentioned my very simple usage for these buttons I can't for the life of me see no reason to not at least try and see about wiring up the buttons individually even if for the time being I simply combine all of the individual wires into one that can go to the Message Centre Cycle button and DTMF Tone Generator. That way I can at least later on assign them to something if I want. Here on the right you can see I have already broken the connections that linked the buttons in strips together making them separate. I also drilled in a tiny hole big enough for some black 22 AWG wire to poke in through the back of the white plastic back board and soldered them to the wire.

Testing A Few Buttons

Now I did not want to go super crazy soldering in a whole bunch of wires without at least doing a test on a couple first to see if my somewhat crazy idea was even going to work. So what I did was rig up just a few and then place the sheet of Brass or Copper buttons over top of my make shift switches and see if I get a reading on the Multi Meter when I press the buttons..... I actually do. Now you can see on the back of the actual plastic buttons I had to cut off of the original Texas Instruments Calculator with my Dremel that they will have a much more precise pressure point for pressing the slightly domed metal buttons on the sheet.

So over all I think theoretically anyways that my idea should work. I have even so far made an overlay or bezel for the Space Matt Buttons using some black plastic scrap I had kicking around. I need to even out the edges a little and smooth it all down but I think once it's painted and my buttons are all wired up and I do some testing of the final array before installing it into my Lower Console it should work. Now depending on how well it works I might just say to heck with it and just go with it.