SOLD: TRS-80 64k Color Computer $25

Off Topic MakerTrade
#1

I picked up a Radio Shack TRS-80 computer the other day for $25 and really don’t have a use for it other than it was a “good” idea at that moment. It seems to be in working order and does not have any accessories. This should really go to someone who would appreciate it, before it ends up in the back of my closet.

Looking to get the $25 I have in it back, or I would be willing to donate it to the appropriate committee.

TRS-80 64k Color Computer
Model 26-3003B
Serial 0020597

Computer https://drive.google.com/open?id=1byw2GtpcNNzdQc4u41xOe_qHK37fx-Zw
TV Output https://drive.google.com/open?id=12yTetWOtyrGmKPCop9NFh3MuIwcIH3Ik

1 Like
#2

Nice, one of the later white full sized ones with a melty keyboard. :slight_smile:

If I didn’t already have one I’d take it off your hands for the $25.

#3

If that was a CoCo 3, I’d be all over it…

#4

If I overpaid for it, feel free to make an offer, or heck, I might even trade it for some good craft beer :beers:

#5

I’ll give you 25 for it.

#6

Awesome, sent you a message.

#7

unrelated, got one myself anyone who’s buying know or wan to rpogram in color BASIC? Also got dungeons of daggorath if anyone wants to try

#8

Somewhere I have a handful of duplicate cartridges and some extra controllers that are good trade bait. :slight_smile:

#9

any chance you’ll be at the retro game meetup sat@6?

#10

Or retrocomputing at 3

#11

No.

I’ll be in Louisiana with my wife (a fellow DMS member) Robin while she presents:

https://www.natchitochestimes.com/2018/07/09/crnha-lunch-and-learn-the-great-raft-of-red-river-is-saturday-july-14/

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#12

Thurs around 6pm in front of the Makerspace building okay?

#13

That sounds very interesting Raymond!

#14

Back in the day I had a 16k model. I piggy backed on a set of 4116 Mostek RAM chips and soldered all pins except bank select which went off to another pin. Probably the only 32k Color Computer around.

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#15

Nice, Brady! I seem to remember our 16k model actually shipping with 32k. Hmmm …

Interesting … from wikipedia …

… The early CoCos only had eight RAM sockets, so upgrading to 32K requiring piggybacking two sets of 4116 chips and adding a few jumper wires. A later motherboard revision removed the 4K RAM option and were upgraded to 32K with “half-bad” 4164 DRAMs. These boards have jumpers marked HIGH/LOW to determine which half of the memory chip was good, in addition, they removed the -5V and -12V power lines used by the older DRAM types. This was transparent to the BASIC programmer since in either configuration 32K of memory was available. As memory production yields improved and costs went down, many (perhaps most) 32K CoCo 1s were shipped with perfectly good 4164 memory chips; many utilities and programs began to take advantage of the “hidden” 32K.

I guess I did remember that correctly.

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#16

Thanks for the background. This was in the 70s - more than a decade before Internet and decades before Wikipedia and the wonderful sources of info we have now. Right here in Carrollton, Mostek was producing more 16K RAM than anyone else in the world. A Mostek engineer friend sketched off a schematic and I got out the soldering iron not aware that it was a common procedure.

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#17

Started case rest

Phase 0ne
Phase 0ne.jpg2448×3264 1.49 MB
oration… Guts later