CompyCoco2
This is a basic RF modulator style composite video board for the Tandy / Radio Shack Colour Computer 2
The channel 3/4 switch acts as a Colour / Mono switch, or you can use a jumper or other switch installed at JP1.
This is a little bit of an involved install, in that you not only have to remove the RF modulator, but you have to extract the MC1372 from the remodulator (or source new ones I guess) and then drill two mounting holes in the system board to mount the stand offs. You can lay the composite board on top of the system board to mark your holes before you drill. Make sure you remove the solder mask under the standoffs, as the composite board is grounding through there.
There were two styles of RF modulator in these computers, and this project is for the style where the RF modulator lays flat against the system board. This circuit is roughly based on a schematic in the Motorola MC1372 data sheet and what parts I had on hand.
The CRT is hard to photograph, but I included a picture. Image looks acceptable to me here, though I suspect it could be improved with some changes to the circuit.
This is free for non-commercial use. You're welcome to make these for personal use or friends for a nominal time and materials fee, but please don't sell them commercially in online stores or on eBay/sell my retro and such.
Thank you.
Happy SepTandy 2024!
CompyCoco2
*PCBWay community is a sharing platform. We are not responsible for any design issues and parameter issues (board thickness, surface finish, etc.) you choose.
Raspberry Pi 5 7 Inch Touch Screen IPS 1024x600 HD LCD HDMI-compatible Display for RPI 4B 3B+ OPI 5 AIDA64 PC Secondary Screen（Without Speaker）
BUY NOW
ESP32-S3 4.3inch Capacitive Touch Display Development Board, 800×480, 5-point Touch, 32-bit LX7 Dual-core Processor
BUY NOW
Raspberry Pi 5 7 Inch Touch Screen IPS 1024x600 HD LCD HDMI-compatible Display for RPI 4B 3B+ OPI 5 AIDA64 PC Secondary Screen（Without Speaker）
BUY NOW
- Comments(5)
- Likes(4)
More by lowlevel 76
-
CompyCoco2
This is a basic RF modulator style composite video board for the Tandy / Radio Shack Colour Computer...
-
Is72423Now
I needed a hard to find RTC72421 chip for my Amiga 2000 and opted to install a surface mount type in...
-
ASCIITRAN Apple II Keyboard Translator
This sits between an ASCII keyboard and the Apple II to 'change' the ASCII values to whatever values...
-
Compy 2600 - Atari 2600 Composite Mod (NTSC)
Encountered a rather poorly done composite mod in an Atari 2600 (NTSC) and decided the best way to c...
-
TI-99/4A Atari Joystick Adapter
The standard TI-99/4A Joysticks are pretty awful. I made this to let me plug my favorite Atari stand...
-
Apple IIc / IIe Paddle Joy
Now you can use those old apple II paddles on the IIc! Or if you have a IIe, you don't have to open ...
-
-
Commodore 64 1541-II 1581 Floppy Disk Drive C64 Power Supply Unit USB-C 5V 12V DIN connector 5.25
173 1 3 -
Easy to print simple stacking organizer with drawers
88 0 0 -
-
-
Modifying a Hotplate to a Reflow Solder Station
1141 1 6 -
MPL3115A2 Barometric Pressure, Altitude, and Temperature Sensor
642 0 1 -
-
-
V2 Commodore AMIGA USB-C Power Sink Delivery High Efficiency Supply Triple Output 5V ±12V OLED display ATARI compatible shark 100W
1456 4 3
1N3064 is what the Motorola 6847/MC1372 datasheets provided in their example composite circuit.
I think you can use a 1N4148 instead.
Hi David, there is no equivalent as far as I know. The MC1372 is a colour tv modulator chip... the intention is you carefully remove it from the RF modulator or source it somewhere else. I did have a look at the BOM and the mention of 8-channel analog multiplexer-etc is an error. I will try to update that when I can... but please ignore that. You need the MC1372. Sorry for any confusion.
Thanks for your response, OK Iets remove the MC1372 very careful!!