channelmaniac

I don't have it on my site, but if anyone wants one it would be a matter of ordering the EPROM and a custom programming fee then telling me you want the dual BIOS on it. It takes a 27128. Any speed or version (CMOS or non-CMOS) will work. It's so simple that there really isn't a need to put a "kit" together for it. All you need is: The BIOS chip 2 wire jumpers 3 pieces of wire 28 pin socket And, of course some simple hand tools, including an Xacto knife to cut the 2 traces for the mod. RJ

It's done and working well! The audio from the expansion module is there and sounds great. I'll get a pic taken tomorrow and update the doc then put them on the website. Sweet! Did you do the audio mod too? Tapping off of C88 works great and you get audio from the CV and from the Expansion Module. BTW: It wasn't my schematic, I just built a PC board for it.

I have a case bottom, but no top. It came with a board I refurbished. RJ

Open it up and swap the controllers around. Maybe you have a broken wire. If that's not it then you'll need to replace the AY-3-8914 Audio and I/O chip. Funny thing that Mattell (or should I say MattHell) did... they use a chip that is pretty close to identical to the AY-3-8910 chip which is commonly used in various arcade games but with a different register layout. Go figure.

I picked up a few tubes when I was out in the Bay area last year. I love scrounging surplus electronics places! The 4164 chips will work just the same as long as you have the extra address line tied high or low to keep it from floating and switching banks at random. Since it's on pin 9 and pin 9 is left tied high by the instructions I wrote up it'll work fine. They are all 1/4 watt. There's no need for anything bigger and I don't care to use anything smaller. Done! Thanks to BigO loaning me an expansion module I'll have it tested tonight for audio output with the different tap spot. If all goes well then I'll take a final picture of the audio tap spot and adjust the installation guide to finish it up. I already have 10 kits assembled and waiting - one goes to BigO for letting me borrow his module. Raymond

The 48 in 1 and 60 in 1 JAMMA boards run on an Intel XScale processor. RJ

It all depends on the parts you are looking for and what I have at the moment. I concentrate on chips so other parts aren't always saved - and the consoles I deal with aren't pretty enough to typically save case parts from. Everything gets shipped by USPS Priority Mail as that's really the easiest way to integrate shipping into the checkout on the website. RJ

Tops will work for many different GAL chips. I used one exclusively until I bought my ROMMax programmer from eeTools.com. Just beware... Your PC USB port must be able to supply enough power You cannot be running Vista The power issue shouldn't be a problem for GAL chips but IS a problem for older EPROMs. RJ

Hey Ninoy... Drive over to Lewisville. I'll hook you up with a TIA. I have a bunch sitting on antistatic foam that I haven't put up on the website yet. They go for 6.99 on my site. RJ

My favorite thing to build with an Altoids tin is something that goes BOOM. Fill it with Tannerite and take it to the rifle range. (At least as long as it's still legal to do...) Tannerite requires a large shock to be set off, hence the rifle range.

I think I know what your problem is. It's that you didn't get the "puckman.zip" file. You need that play the midway version which is the clone of puckman.zip. It has certain ROMs needed for the Midway version to work. BINGO! If the ROM file has any dependencies you'll need to download the other file too. For Pac Man and other derivitaves you must have the puckman.zip file. The other Pac Man files only have the ROMs that are different from the ones in Puckman. In other words, not a full set of ROMs needed to run. RJ

I for one *love* the concept and the archives of MAME. It allows me to play with different ROM images to see what corrupt code does to the game AND it's an amazing source for ROM images to repair real game boards.

My money is on the 6532 RIOT chip. RIOT = RAM, I/O, and Timer. The RIOT chip is the other 40 pin chip besides the TIA in the system. It appears that you have a RAM issue. RJ

OK... So this Colecovision has been upgraded to 5v only DRAM (MK4516), composite video, dual audio outputs, and a selectable BIOS. I documented the RAM upgrade and BIOS upgrades on my repair log site if anyone is interested. It's no longer finicky about power with the 5v only DRAM in it. A few zip ties to tame the wires and it'll be done. (The big black blob is the video upgrade board. It's enclosed in some heat shrink tubing.) RJ

PM sent. PM replied!

OK! That should be solved. According to the CV schematics that audio comes in on pin 31 from the expansion connector, goes up to the back of the board near the RF modulator and goes through C88 to meet up with the audio that comes from the SN76489 audio IC. If you take a hobby knife and scrape a bit of the coating from the ground plane between C88 and the RF modulator then you can tap the audio from the leg of C88 closest to the RF modulator and solder the ground wire to the ground plane where you scraped the coating away. I tried it tonight and it works well still from the audio IC but I don't have an expansion module to test it on. Does anyone have one they'd be willing to ship me for testing? I'll reimburse shipping costs and send a kit with it when I return it. RJ

Thanks! I'll have to get one of those mods and see what I can do on the audio part. I tried the mod with a 13" color CRT TV I have in the shop and with my Sony Bravia HD Monitor. RJ

It works, and it works very well! I have 15 kits almost assembled. I need to get the wires cut to size and put in the bags with everything else and they'll be done. I also put together a beta draft of installation instructions. (attached to this post) Once it's finalized I'll convert it to .pdf. Basically, everything needed is in the kit except for tools (of course) and a small piece of double stick tape to hold it in place. Now I just have to add up all the parts and pieces and figure out a price. RJ PS: I already see a grammar error and a glaring omission in the doc. I forgot to put the step in about putting the heat shrink tubing over the board and using a heat gun or lighter to shrink it. Colecovision_Audio_and_Composite_Video_Mod_Installation.doc

There's your static. The Nintendo switch box requires voltage to switch and the CV doesn't send it. Get a simple RCA video cable and a phono female to F male adapter. It'll plug right into the coax connection on the TV and work well. RJ

I should have 30 of them by the middle of next week.

Here's the pic of the assembled board. I used a single 75 ohm resistor instead of 2 150 ohm ones in parallel. Some tiny coax will hook up the inputs and outputs. I tried to keep the inputs, outputs, and their grounds close together to make it easy to use that kind of tiny coax. The +12v and ground for power are separated on the board but that shouldn't matter any since those are separate wires anyway. I'll try to get it installed tomorrow and post pics of what it looks like when running. I'm thinking that I can use some big pieces of shrink tubing to cover the whole board and just let the wires come out the open end of the tubing. That way it's easy to use some double sided foam tape to stick the board somewhere where it won't bounce around loose in the case. RJ

Maybe Mouser or Jameco... but Jameco has a high dollar minimum order. The op-amp used in that circuit isn't too easy to find as it's an old part. I just happen to have a local surplus parts store that had them. I'm digging out from under a LOT of repairs that have arrived in the past week. Once I get some breathing room I'll finsh up this modded one and let you know.

Not sure yet. I have to add up the cost of the board, components, wire, and jacks but first I have to test them. I still haven't assembled one to see how it looks. The one I built on a waferboard looked great and I expect this to work fine, but you never know with a video signal. I'll also mod that one with 4516 DRAM (5v only DRAM) for less power draw, cooler running, and more reliable operation and sell it on my website to see if there's a demand for pre-modded systems.

I did and liked the results. I designed a small circuit board for it (less than 1" square double sided) and ordered 30 of them. I'll be soldering them up into kits and putting them on my site. RJ

Carts are gone.