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  by Bill Degnan - 01/10/2020 12:28
Ohio Scientific Challenger 1P mods
Here's a nice view of the BREAK/NO BREAK wiring and toggle activation switch. With this MOD, one can disable an accidental softboot caused by pressing the BREAK key on the keyboard. Click image for larger view.


BREAK mod pic2
BREAK mod pic3

Ohio Scientific Challenger 1P mods
Here's the view from the underside mid-board edge conenctor. From this angle one can see the TAPE toggle (bottom right) and to the left of the large circular fan opening, the serial port. (Follow the purple/blue/green wires) Click image for larger view.


wiring pic2

Ohio Scientific Challenger 1P mods
Pictured is a view of the mod wiring from the underside of the the corner edge connector. From here you can see the SUP-R-MOD RF adapter, video port and cassette ports. Click image for larger view.

wiring pic4
wiring pic5
wiring pic6
wiring pic7
wiring pic8
wiring pic9

More photos (full motherboard, power, etc.)

NEXT: I should have most of the schematics, or I can pretty easily plot out the circuits for these mods for support purposes. One would have read articles describing these mods, with schematics, from old magazines like 6502 journal or MICRO, Kilobaud, etc.

When I get the chance I will post more info if I discover something useful that is not already out there.

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