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Last update November 15,2005

By Glen VanDenBiggelaar

Tandy and other third partied released hundreds, if not thousands of accessories for the CoCo. You must remember that this computer had a retail life span of over 10 year, and now 25 years later, there are still a loyal few who are making new products for the CoCo ( like Cloud9tech). I will try to just touch on the more important ones.

 


MASS STORAGE
Now, as you know, Hard drives were (and most storage) was very expensive in the '80's, and the simplest and cheapest storage device was Cassette tape. The were cheap, abundant and everybody knew how to use a tape deck. Certain companies tried to market "DATA CASSETTES" claming that your computer's data should only be backed up to them. They were about double the price of a regular cassette, but, we never saw any difference.

The most common "add-on" was the cassette deck. This was a full cassette Deck, and RS must have sold millions, not just for computers. Long after our CoCO was retired, the Cassette deck was and still is working great and being used today. We only had one saying when a program was being loaded with it. "Don't bump, breathe or even look at the cassette deck" otherwise we would have to re-load the program.

One of the first "tricks" I learned on the computer, was to put a music tape in and just type in "run" and the music would play though the TV's speakers. My parents thought I was a programming genius. There was at least 3 Models that Radio Shack sold-
CTR-80A #26-1206
CCR-81-This cassette deck came in 2 colors. White (shown Right, and an older gray/silver color to match the CoCo1.
CCR-82 Very compact # 26-1209

The tape drives were compatible with all Tandy computers (even laptops), not just made for the CoCo.



Floppy Drives and Controllers
Tandy and Motorola did not incorporate the Floppy Drive Controller on to the motherboard, like in today's computers. So, you had to buy both units. Sometimes, they were sold in sets (Have photo soon), or you could buy them separate. I will start with the different controllers.


Floppy Drive Controllers

 
26-3022
This first model of CoCo floppy controller was packaged in a long cartridge, and was introduced for use with the original CoCo. It uses a WD1793 controller chip, which requires +12V DC. For this reason, a multi-pak interface (or other source of +12V) is required to utilize this controller with a CoCo 2 or CoCo 3. This controller also uses an analog data separator circuit, infamous for its inherent unreliability. However, this controller is the only one capable of being modified (though with considerable difficulty) to allow use with high-density 3.5" floppy drives. All subsequent controllers use the WD1773 controller chip, do not use the unreliable analog data separator, do not require +12V (so they will work with any CoCo model), and are capable of double-density operation only.


Collection Photo

26-3029
This model was introduced for use with the CoCo 2 (as it lacked the original CoCo's +12V power supply), and is also mounted in a long cartridge


Collection Photo

FD-500 (26-3129)
This model is also mounted in a long cartridge. It appears to be identical to the 26-3029. (NOTE: Some Sources state that the Tandy name appears on these, but as you can see in this photo, that is not 100% accurate)

The "Tandy" logo 500
E-Bay Photo


Ebay Photo
FD-501 (26-3131)
One of the more 'modern' controllers (mounted in a shorter cartridge than the older ones), this is also the only Radio Shack model ever to feature gold-plated card-edge connectors. Due to the much higher reliability of gold contacts over tinned PC fingers, this is my personal favorite among all of the Radio Shack controllers. This model was introduced in the 1986 Radio Shack catalog.
Ebay Photo

FD-502 (26-3133)
This is the last Tandy controller. It reverted back to mere solder-tinned edge connectors, for whatever reason (cost?!). Unlike every previous model, this one uses a 28-pin ROM rather than a 24-pin ROM for Disk BASIC. This model was introduced in the 1988 Radio Shack catalog.
All Radio Shack (and some third-party) CoCo floppy controllers use a pair of 7416 open-collector buffer chips to communicate with the floppy drive(s). These chips can fail and cause various strange symptoms. They may be replaced with 7406 chips, which are more rugged (the 7416 is rated at 15V, while the 7406 is rated at 30V). Socketing the replacement chips makes future replacement much easier, should it become necessary.
UPDATE: It has been suggested by Robert Gault ( A big chief in the CoCo community) that these are the only controllers that will work properly on an un-modified CoCo 3. When recently asked about which controller is better for a CoCo 3 and Double sided drives, his response was:
"It is not likely that you would notice controller differences in normal use. The 501 controller is reported to be more useful for hardware hacking and running at different speeds. But it needs both 5 and 12v power so won't work with an unmodified Coco3. I think the 502 is a 5v only controller that would work with the Coco3.
The 501 should not need modification to work with double sided drives. That is a function of the DOS .
If you want to keep just one controller, I'd suggest the 502.


Collection Photo
Floppy Drives
  
26-3022 'Color Computer Mini Disk'
These original CoCo floppy drives were gray in color, matching the exterior of the original CoCo (and other early TRS-80 machines and peripherals). They use a 5.25" full-height TEC (Tokyo Electric Corp.) drive mechanism, infamous (like the mating controller) for reliability problems. The drive unit stands vertically, making it taller than it is wide. It was reportedly capable of accessing only 37 tracks or so physically, prompting Tandy's incorporation of the 35-track limit into Disk BASIC. These (and all subsequent) drives were double-density and, like all but the very latest model (FD-502), were single-sided. This resulted in a capacity of approximately 160 kilobytes per disk.
Ebay Photo
26-3029 'Color Computer Mini Disk'
This drive model had a white case, but was still a full-height, vertically-mounted assembly. These first two styles have 34-pin card-edge connectors on their rear panels rather than captive ribbon cables. The addition of extra drives required using additional case/power supply/drive units.
Ebay Photo
FD-500 (26-3129), FD-501 (26-3131)
All subsequent drives were also white in color, but were mounted horizontally and used half-height drive mechanisms. They shipped with a single drive (Drive 0) in the lower 'bay', and a blanking plate over the upper opening. These drives could be upgraded to a dual-drive system by installing the second drive kit in the existing case. Note that the kit included, and all dual-drive installations in these cases require, a 12-volt cooling fan. The units run acceptably cool with a single drive, but not with two drives. The 4 cm diameter, 1 cm thick brush less fans (as used on many CPU heat sink assemblies) work well in these cases.The 500 had 2 venting slots, 1 at the front and back.the 501did not have the venting slots on top, and the 502 had 2 rows of vents near the back.


FD 500 Ebay Photo


FD 501 Ebay Photo
FD-502 (26-3133)
This drive unit is like the FD-501, with two notable exceptions. This is the only Tandy model ever to incorporate true double-sided drives, and its drive power connectors are like those of typical 3.5" floppy drives rather than those of normal 5.25" drives. The smaller power connectors are also reportedly wired differently than typical 3.5" drive connectors. As noted elsewhere, either a patched Disk BASIC or an alternative operating system is required to gain access to the second side of disks. A cooling fan must be installed for safe operation if a second drive is added.


FD 502 Ebay Photo


An interesting oddity about the 502's that was pointed out by a Dave F. The 502 came in 2 different cases (both manufactured in Korea) The "American Model" had Slots for venting with a wire screen underneath. On the back sticker,it stated "Custom Manufactured in Korea for Radio Shack"


The Canadian Market saw a slightly different 502. This had no "screen" and square holes instead of full slots.On the label, it read "Made in Korea, distributed in Canada, by Intertan Canada LTD.
Hard Drive Controllers
  
26-3145 
Talk about a rare item. I have only seen 1 posted up on e-bay and within minutes of the positing the bidding was up to $50.
The hard drive controller was to be used with Tandy hard drives that they made for the Model 1, 3 and 4 computers
The Controller package (E-Bay photo)

The TRS 80 15 Meg Hard Drive (E-Bay photo)
MPI
  
Multi-Pak Interface
In order for you to hook up more than one device at a time to the CoCo you needed the MPI.

silver old CoCo 1 Style
E-Bay Photo
The Multi-Pak interface Using this module you can load up to four cartridges and toggle back and forth without having to remove/load each cartridge .
There were 2 (that I know) produced, I am not sure of anything beyond cosmetic differences.
Original "old Co Co 1" Style model #26-3024


Photo from my collection
Newer style Model no 26-3124
Ebay Photo
Others  

Color Computer Appliance/Light controller ( 26-3142 )

Ebay Photo
There were a few modems produced for the CoCo


Ebay Photo
There was also a wide variety of printers

Joysticks- a few types were produced
26-3012B" Deluxe Joystick" and 26-3023
NOTE: These could also be used on the TRS-80 1000 Computer, and IBM had the same Joysticks made under the "IBM" logo for the PC Junior. I have even seen the 26-3023 Made for the Commodor 64 and Atari Computers exactly the same -just without the "TANDY" name on them. I will put photos of the clones up on a "photo" page soon.
The first "regular" joystick is in my opinion the best. It featured an all metal, tapered stick and instead of a "ball in socket" had actual hinges. It also had a thicker gray cord than the usual black. All 3 variations had the same catalog number, so it is unknown when Tandy changed design. The second model had a much thinner stick and a plastic "ball in socket". The plastic joining the stick to the ball, was very thin and consequently could be bent or broken quite easily. These just had the regular black cable. The final stick was an all plastic design hand had the word "japan" stamped on the bottom. these sticks were stronger than the second, but the thin plastic stick felt ocward compared to the original tapered stick.

Model 26-3008 regular Joysticks. These came in 3 different forms. the sticks were metal (early production) or plastic (like photo above).

The TRS-80 "Deluxe joystick" .This only had one fire button, but is identical in every other way to the "Tandy" Version. 26-3012

Mice-

Tandy made at least 2 different models of mice

the "Regular" one Button Mouse 26-3025.
Tandy called this the Color mouse, and it had the same "Feel" as the early Apple Mouse. It had a big steel ball inside and was quite heavy, with no access panel an the bottom, the only way to clean it was to take the whole thing apart.

Interesting side note:
The package shows a silver mouse, but so-far I have only seen black,with a big red button. Were the first produced silver (gray like the CoCo itself)? If I ever find out I will update the page.


E-Bay Photo

The Tandy Deluxe Mouse with 2 buttons 26-3125
This mouse was regular $69.95 here in Canada, a far cry from mice now. what is interesting to note, this mouse did not come with a "access" panel to remove the STEEL ball, so you had to disassemble the whole mouse to clean it.

Tandy did have nice protective packaging for their mice, it consisted of a big styrofoam block with a interlocking styrofoam cover and a cardboard sleeve for the graphics. The instruction manual sat nicely in the styrofoam "Cover".


Canadian Packaging with both French and English (photo from my Collection)

US Packaging (E-Bay Photo)
Third parties even made Mice

This one is called "The Rat" (E-Bay Photo)

TRS 80 Speech Sound Pak (26-3144)
This Cartridge made your CoCo talk.


E-Bay Photo
Tandy Stereo Music Synthesizer (26-3143). You could compose music from your keyboard.
E-Bay Photo
Tandy even made Graphics Tablets- Like the TRS 80 X-PAD
E-bay photo
Third parties like Koala Made graphics tablets for all 8 bit machines. This is officially known as the Koala touch pad. This unit is a lot smaller then the X-pad.
Arguably, one of the most useful accessories to the CoCo was the addition of the RS-232 Pak (26-2226). This controller made possible many things, including networking CoCo's, obtaining modem speeds unheard of, and communication with other devices such as printers etc.
E-Bay Photo
   
   

 

 

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