[Coco] Is there a modern replica CoCo for sale?

[Rocky Hill]

 Thank you for offering to "warehouse" components, that will be very  
helpful!
Assembling a CoCo 3 board from scratch was both a challenge and a  treat and I highly recommend doing it if you can. If you're interested  in building a CoCo 3 from scratch, keep in mind that there are a  handful of custom chips that are no longer made so you'll need to use  replacements designed by the community and that John Strong is in the  process of perfecting a CoCo 3 case. At the moment you can make a  working CoCo 3 board with what is available without killing a CoCo 3  and except for the slight offset with the RF-modulator it's complete.  
That said, you might have a CoCo3 board that was killed during a mod  and can't be fixed or the damage is so bad that it doesn't make sense  to repair the board. In that case you can use the chips from the bad  board and have a working CoCo 3 again. Another scenario could be one  where you want to mod your CoCo 3 but you don't want to risk damage  to the original board.
You can get the design from the bit-preserve project or from my fork  of the bit-preserve project which will have the latest updates.  
https://github.com/qbancoffee/bit-preserve  
There are many proposed systems in the project so you'll need to  navigate to the right directory after downloading.   
bit-preserve/Tandy-RS/TRS-80 Color Computer/Color Computer 3  bit-preserve/Tandy-RS/TRS-80 Color Computer/Color Computer 2/26-302x  

The CoCo plus plus board I'm working on will mostly be built with   surface mount components plus an assembly service making it cheaper   with fewer through hole components to solder.  

Thanks!  
Pedro  

    On Saturday, December 18, 2021, 06:26:03 AM EST, Charles Hudson <charles484 at twc.com> wrote:  
 
 FWIW I am interested in finding out more about the Model 3 and had 
considered acquiring one but actually would prefer to build one.  So if 
and when you finalize the design for the board please let us know.

When the BOM is finalized I might be able to act as an intermediary for 
some of the minimum-quantity items; for example if 10 germanium diodes 
are needed but Mouser or DigiKey only sell them in quantities of 500 I 
could "warehouse" them and pass them on to those who need the smaller 
quantity.

I guess what I'm saying is that I'd really like to see this come to 
fruition.  Good on you.

-CH-

On 12/17/2021 4:46 PM, Rocky Hill via Coco wrote:
>  Oh I've seen BSG like 4 times already and I think I'm gearing up for a 5th!
> So far the CoCo 3 board works and the only issue I have with it is that when the RF-can is mounted,the connector is offset by about 1mm. It still comes through the case, it doesn't crash into the plastic and it's usable, but I don't want to make the change to the PCB because at the moment I don't have an RF can to make the measurement.It isn't a big deal nor is it a show stopper but I would like to tweak it in the future
>
> I do have a BOM and I believe there is one in the repo. Each component has a part number associated with it and KiCAD can generatea BOM automatically from that info, so you can generate right now if you want. Luckily you can still get modern replacements for most of the components and even the PIA's are still available, part# W65C21N6TPG-14. You can get them from mouser electronics and it's a drop in replacement for the 6821.The components that are hard to get are of course(or is it coarse) the GIME, the SALT and DAC chips.
>
>
> There are a handful of components that are still available but are what digikey calls marketplace components which forces one to buya minimum amount plus an extra shipping cost. These are things like a handful of germanium based diodes that have lower forward voltagesthan silicon based ones and a darlington transistor used for the sound amplifier. I've already ordered some modern replacements that I thinkwill work so when that's figured out I'll place an easy to download BOM in the repo to make things easier.
> As far as the CoCo 2 board goes, I've already uploaded what I consider a finished board and the board is a drop in replacement forthe 26-3026 & 26-30267 model CoCo's. I have a video where I bought two halves of different model CoCo 2 cases from ebay and builta CoCo 2 with this recreation board. That was a fun project and I was able to buy a SAM, a VDG and a 6309 on ebay for around $20.00
> The PEPPER board works and as far as I can tell completely replaces the functionality of the SALT chip while also eliminating the need for Q1.With the PEPPER my CoCo's run cooler and draw less current. I put up instructions on how to order the assembled boards from JLCPCB in the repo.Also withthe PEPPER board you can directly power your CoCo with a DC power supply
> The Daquiri board works with everything I've thrown at it except playing photon. For some reason the little tank goes down when the joystick goes rightand it goes right when the joystick goes down.  I have no idea whats going on there but I would say that the Daiquiri board is 98% compatible with the DAC/ADCchip. Instructions are also in the repo.
> All of this stuff is open hardware and anyone is free to download and order from where they want. Contributions to designs are greatly appreciated as well becausethere are a lot of moving parts and more eyes and experience can be very helpful.
> I don't really sell any of this if that's what you were asking but I realize people may not want to go through the hassle of generating gerbers and ordering boardsto then assemble them so I might start a web store in 2022 for things like this. I have sold some stuff but not much.
> Working on this stuff is fun so.... my pleasure!
>
>
>
> -Pedro
>
>      On Friday, December 17, 2021, 01:18:09 PM EST, Ron Klein <ron at kdomain.org> wrote:
>  
>  I'm a big fan of that reboot as well.  I've been meaning to go back and
> watch the entire series again.
>
> As for the CoCo 3 board -- I didn't realize it was finalized yet.  That's
> great news.  Would you happen to have a BOM for all the necessary parts
> (minus things like the GIME, of course).  I know it won't be easy finding
> everything these days.  I have a spare CoCo 3 case, keyboard & GIME (need a
> power supply, though).  It may be time to bring a new CoCo 3 to life..
>
> Please let us know when your CoCo 2 board is ready (as well as the PEPPER
> and Daquiri boards).
>
> Thanks for all your work on these and for sharing your projects!
>
> -Ron
>
>
> On Fri, Dec 17, 2021 at 11:15 AM Rocky Hill via Coco <coco at maltedmedia.com>
> wrote:
>
>>    1>Athena is a CoCo 3 replica board and being a fan of the BSG reboot and
>> this being a clone board, I named it after "Athena" the good clonerather
>> than "Boomer" the bad clone. Yes I know they are cylons but they are
>> clones.....
>> You can get the kiCAD project from the bit-preserve project and order the
>> boards from your favorite PCB manufacturer.
>>
>> -Pedro
>>
>>
>>

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