Modding a Dina 2-in-1 Telegames Personal Arcade Colecovision

[bacteria]

Well, I bought this piece of shit and it came yesterday. I bought it knowing it was a piece of shit and it doesn't matter.

Let me explain!

When ColecoVision went out of business, Telegames bought their product and remade the large ColecoVision into a far smaller console, the board is about half the size, and as long as you only want it as a one player system it is potentially useful for modding, I hope. They only sold the unit mail order in the States apparently for $40 at the time, finishing selling them in 1994 after a hurricane/tornado (whatever it was) destroyed their remaining stock.

(At least, as far as I recall from spending hours Googling for information)


PROS:

* Small board.
* Compatable with all ColecoVision games (except see Cons section) although is an official "clone"
* Easy gamepad, only got a D-pad and two buttons
* Also plays SG-1000 games, which is what the pause button is for, not the Coleco games
* Light
* Only needs about 300mA to run
* Apparantly can be easily modded to output composite (which is why I got it mainly)

CONS:

* It is a piece of shit, poorly made
* Controllers feel bad and cheap
* Needs 3 voltages
* RF output overheats and makes the image go very light after a while, and stop showing
* Graphics chip (think it's that one) gets very hot and can harm the unit
* The console comes with no instruction booklet, what a piece of shit
* The console DOESN'T Come with a friggin power supply!
* The expansion port doesn't allow you to plug in an expansion unit as the RF and power lead get in the way (duh!)
* The numerical keys on the controller are missing and on the console itself - fine for 1 player not 2
* The numerical keys are 6 x 2 and smaller than the usual 3 x 3, so no overlays fit
* Units aren't plentiful, although do come up sometimes on ebay. I had to get mine from France, cost me about £70 including postage, so not small change
* Hard to get any information on the net, even about voltage of the power supply they don't provide (a couple of sources I found were totally wrong too, which wasn't helpful); could find nothing on that, although I should be able to work it out hopefully; no details on the composite modding apart from ONE post I saw on one forum:




Without going into a rant like Angry Video Nerd, now let me explain why I bought this piece of crap:

If you are going to composite mod the unit, use a different controller (ie your own/modded), happy to install heatsinks and maybe a fan if needed, remove the RF when done the composite mod, want a nice light, single voltage and low consumption unit that should play all one player games, this could be the baby for you! Making all those changes, assuming the composite works ok, will leave a good system!

Here is the pic, got mine as a boxed, new unit (ebay)



So, whilst doing my N64 project, I will be not only trying (still) to get my original ColecoVision unit to output composite; but also modding the Dina console too.

I'll probably open this baby up tomorrow and give more pics, and time permitting (I only have 2 hours for modding tomorrow) will have a crack at modding the system. Nice diversion from my N64 project!

Please, if you know any information about this system not detailed above, please post it here! Also, if you are familiar with the composite mod, please confirm the above post quote was correct!

[pepharytheworm]

Are you going to make a portable Sega SG-1000 mark I, with the rest of the parts? if thats even possible.

[bacteria]

The console takes both cartridges, SG-1000 in the top port and ColecoVision carts in the bottom one.

[pepharytheworm]

I was just curious if you could make both a portable SG-1000 and a Coleco or if that would be possible, since you are the resident portablizer. Would it be easier then using a coleco to make a portable or the Dina. That would be cool to see coleco games and Mark I games in composite.

[bacteria]

With the Dina you can make a dual system portable as it uses SG-1000 games and ColecoVision games too. The board is rectangular, around the same width, but about half the length of the ColecoVision board.

Here is my problem - and i'm having issues getting the answer - the Dina doesn't come with a power supply and looking at the board it seems to take two voltages, although I don't know which line is the 12v line and which one is the other voltage (5v maybe?); if I just take a guess and get it wrong, the board will probably fry.

Anyone know the voltages the Dina takes and can tell me which pins on the power supply plug on the Dina take what voltages please? Anyone else got a Dina console?

[bacteria]

Spent so much time on the power voltages to the board it really isn't funny. Revised my pinouts a couple of times too, which is most annoying.

Spent many hours looking at the board, testing with multimeter, looking on the net for datasheets for these obsolete chips, it wasn't easy.

Managed to find a datasheet (finally) for the AM9016 chip - HERE

Pin 1 = -5v, pin 8 = 12v, pin 9 = +5v, pin 16 = ground.

This also correlated to the link for the MK4096 with the same pinout.

I got a positive beep on my multimeter with pin 2 of the power supply pins for -5v, pin 3 goes to the 10v capacitor and looks like it links to 5v lines so is +5v; and the 12v going to the transistor - well, the output from the transistor goes to the 12v line on the chips so must (should) be correct.

I am therefore gambling on the configuration being:

pin 1 = +12v
pin 2 = -5v
pin 3 = +5v
pin 4 and 5 = ground

Boy, I hope this is right, one way to know I guess!!

Assuming it will work ok, I will show a guide on how to make your own power supply for this system using 7805, 7905 and heatsink. It looks like the 12v line should run off 9v, however I want to see if it will run 7.4v or not. If not, I saw a guide somewhere to make a 7805 output 12v; may not be efficient, however it only needs to manage 300mA. Experimentation needed!

The amperage for the system seems to be (based on a few posts I found which all agree with each other):

+5V 900mA
+12V 300mA
-5V 100mA

I will be doing my N64 project next week as planned, it's just that I have a bit between my teeth at the moment with this Dina system!!

[bacteria]

Wiring was right for the power to the board:

pin 1 = +12v
pin 2 = -5v
pin 3 = +5v
pin 4 and 5 = ground

Really easy to get composite too, just wire to pin 36.

Problem is the composite output has a rainbow effect. This is documented about the TMS9918A graphics chip. You get colours all over the place that shouldn't be there. it's a pain and can't be resolved; going to spent tomorrow trying the new chip on the old ColecoVision board to see if I can get that to work, and if it works better or not.

[bacteria]

Ok, was really fed up with the Dina system. Audio sucked, couldn't improve the composite, and to top it all, it was working ok and then stopped. All I did was try to run the RF plug into an old television, like it was meant to be. What a piece of shit. Even the cart plug is bad, grips onto the game cart like it's life depended on it!

So, a few notes:

Here is the Dina board:



I can confirm this is the pinout to power the Dina 2-in-1 console system:





I used a ColecoVision power adaptor.

Spoken to an electronics provider, they say an easy way to get a negative voltage is to put the voltage of a battery across a regulator (like a 7805) and wire positive to negative and negative to positive....

I then did something risky, but worked:

As the Dina fried (no idea how), used dremel to cut off the pins on the TMS9919A chip at the base to keep all the pin I could easily; and on the ColecoVision, used strong pliers to lever off the heatsink and then cut through the top of the chip pins on the TMS9929A chip.





Placed the new chip over the old pins, pressed down to make them touch as best as could. Applied some flux, and tapped each pin with solder so the pins were tinned and at the same time filled with solder bridging the pins together. One pin didn't connect, so the graphics were jagged badly, found culprit and re-applied.

Pic shows half-done chip.



Result - probably as good as it gets unfortunately, colours are fine but you get the rainbow effect - can't be helped as apparantly this is what happens on the Coleco with composite mod.

It looks better than shown here...



Sound is tapped off here:



And video (composite) off pin 36 - lift off pin 36, wire a 460 Ohm resistor to it and connect to ground. At pin 36 wire to the composite connection. (result in above screenshot).



I will experiment with this more tomorrow to see if using a different resistor or wiring it differently makes any difference at all. Will also experiment by using a different screen too.

[fastbilly1]

Damn impressive soldering on that chip

[bacteria]

Thanks! Not done that before. Tried desoldering but was going to be hard, so used the dremel instead!