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What does it do with the standard VDP?

Most newer flat screens will switch between Pal and NTSC automatically. Older TV's wont. The Canadian coleco is the same as the USA one and is composite only. NO RGB. The VDP's are different between PAL and NTSC models. https://en.wikipedia.org/wiki/Texas_Instruments_TMS9918

I'll reiterate some very good advice, I was given. This has helped me fix a bunch of colecos. ok, I watched you video. Isolate the issue, is it processor / bios / sram issue? or VDP / vram issue? Get yourself a frogger cart. (This is really helpful when it's a total black screen, no bios) Boot it, and see what happens. If the music etc powers on and screen stays blank, then its towards Vram VDP issue. (I'm pretty sure this isnt your issue, since bios posts proper) If the music cuts out same as video then it's towards processor bios etc... (The green screen I'm fairly sure is the monitor when video signal drops out. Normal, after a few min video drops if no selection. Try on your working one.) Remember the controller buffer chips are on the same bus as the bios. If the controllers are unresponsive this is where I would go next. If you can socket the VDP you'll have no prob pulling the buffer chips. Pull 1, socket it, on your working machine. Then try the chips from your non working machine, in the working one. That way you can test and not guess. My test mule coleco is fully socketed for just this reason. Post back and keep us updated.

Yes, I did. There is some ambiguity however for modding it will all work. Pins of Coleco 73192, Expansion mod 1. 1 - GND 40 - (controllers) 2 - 27 on 6507 39 - (controllers) 3 - RDY - 4700 res 38 - (controllers) 4 - (Sync or LUM2)? 37 - (controllers) 5 - (Sync or LUM2)? 36 - (controllers) 6 - LUM1 - res ladder 35 - (controllers) 7 - LUM0 - res ladder 34 - AB0 8 - NC? 33 - AB1 9 - COL -2 1kohm match 32 - AB2 10 - DEL - Color adjust pot 31 - AB3 11 - Clock signal 30 - AB4 12 - DB00 29 - AB5 13 - DB01 28 - AUD (shorted from pin 27) 14 - DB02 27 - AUD - R25 - pin 36 exp aud out 15 - DB03 26 - 02 - pin 28 6507 16 - DB04 25 - R/W - pin 26 6507 17 - DB05 24 - AB12 18 - DB06 23 - Goes to AUD out thru 1kohm res 19 - DB07 22 - VSS - pin 2 6507 - GND 20 - VCC - +5 pin4 - 6507 21 - AB7 So... We know there are differences, like Atari pin 4 = Pin 2 Coleco etc... I dont have a Gemini to look at but if one looks at the resistor ladders on the Atari diagram, you can see Coleco copied it just on different pins. Thats the best way to differentiate the lumas. The Gemini uses 8403 or 8402, not sure if they are the same lumas out...

So full disclosure, ​My TV is a Sony with analog YPbPr inputs, it might clean up the signal before displaying. ​ I did try this on another members LCD TV, and the black was a little blue and I had to adjust it. So it's not universal values on the resistors/pots. Hence why I wanted a component to HDMI module, that way it should have a universal output for any TV. I did email him and asked some technical questions, and yes this does relate to clamping and DC voltage being passed on, on the AC signal. Easiest / cheapest is resistors vs Op amp solution. ​ ​ ​

http://www.labguysworld.com/TinyTriniscope_001.htm www.labguysworld.com/YUV2RGB_Matrix.htm I used the formulas from here. Tested on sony crt, didnt loose yellow. *edit, added 2nd url, you get redirected, but he has link mid page with schematics and formulas, also has waveforms for scope work* ​ ​

Guys, For anyone that wants to make an analog component signal for the Coleco, it's super easy.. assuming '28 VDP Pin 38 Red Pin 36 Green Pin 35 Blue Put 100ohm resistor in series, adjust the blue so the screens background is black. If you find a cheap component to HDMI adapter let me know since most seem to be digital. YPbPr VS YCbCr. ​ ​ ​ ​

Ha! Great minds think alike! The major issue when I looked at it would be the install height. Micro switches would probably be to high. However, with great companies like Snaptron, OSH park, Itead, if you make an eagle file the boards can be made somewhat inexpensively. My issue is "making" the legacy components in eagle.

So first off you could be looking for the holy grail. The TMS27C49, 24 pin eprom. However since space is limited, I'm amazed no one has cooked up an adapter board as of yet. Say PLCC or SOIC to the uncommon 24 pin output. (depends on where the space is limited.) Or even an adapter board to "move" the chip over. Some perf board and a couple of sockets should get you there, however I'm not sure if the PAL board is reconfigurable to accept the 28 pin eprom. Some pictures might help.

You must be dealing with a European coleco. The North American one has "extra" holes allowing you to change to a common 28 pin eprom. The 27c64 is a 28 pin eprom.

If your using something like the mini pro, it should work. Try turning the menu off and go bare bones. http://atariage.com/forums/topic/230688-tl866cs-minipro-eprommer/

Ok, so it does work..... However, if all else fails read the data sheet. Tie the extra data lines etc to ground, if it's just straight socketed, pins 1, 26, 27, are tied to pin 28 and 28&1 are tied high.(+5), so slight rework is needed. A 27c64 would make things much easier, plug and play.

The riot and processor can easily be found on ebay. I started pinning out the Coleco VDP, it is definitely different than the Atari TIA, perhaps even slightly different than the coleco gemini one if they did it correctly. Lumas are different positions. I have no source for the Coleco tia. So if it's dead, i'm afraid you might, have a paperweight.

Just trying out some eeproms, winbond w27c512 anyone else use one of these for the no delay bios? I do a write and verify, data all seems to be there, but coleco fails to boot. Starting at 000000... Is this chip incompatible? Thanks.

Ok, So if you want an easy composite mod for your Expansion Module #1, do this. Using the Coleco LM318 board and circuit, and this picture, hook up these wires, Orange - Video in Red - +12V Black - Ground Audio can be grabbed from the top of R26. (Expansion adapter connector side, (Pic is upside down)) I tested it out and it looks good!

missing 6507 and 6532riot I know not atari 800xl but would be REALLY useful for 2600...

Check the voltages out of the powersupply, power it on and see if you get a bios splash screen.

Clean everything with isopropyl, switch, connector, should have nothing on it. Yes the adapter needs to be that big, 4 voltages and all... If you dont feel like sending your coleco away, bios can be bought here, same as the vram if it turns out thats the issue... http://console5.com/store/kits/bios.html

So for anyone who reads this later and wants to try tuning the RF portion of the coleco, check this thread. http://atariage.com/forums/topic/247913-refurbishing-a-colecovision-question/ In the picture, the top one tunes the sound. The bottom one tunes the picture. Make sure to change between channel 3 and 4, to get it adjusted properly.

Hey dude. Have you tried testing the CV by it's self on RF? I know over time in the RF circuit the inductors can drift and need to be re-tuned by a little bit. Perhaps the output frequency is off?

Btw he doesnt mention it in the auction but it looks like it might have an F18a board installed? Has vga connector...

No this is not normal. Btw the Ben heck mod uses a transistor. A better mod uses the LM318. http://solarfox.triluminary.net/hwh_colecoav_p4.php Same as most hook the audio direct to the chip, this can pass on dc voltage. A better audio attachment point is RF side of C88. Your video issue could be a couple of things. Bad vram or dirty cartridge connector. Clean your power switch and cartridge connector. Part 8 right near the end shows what it might look like on the title screen. http://www.colecovisionzone.com/page/coleco%20industries/tech.html

Ok, so replaced the processor with a known good one and it works. In reality only 3 chips in the module. Problem is the Coleco one is different than the Atari one. So if your's takes a dump, there wont be a replacement. Tried the Atari TIA in the EM1 and no go.