Thread: Zx81
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Old 14th Mar 2020, 10:44 pm   #62
John Earland
Join Date: May 2013
Location: Middlesbrough, North Yorkshire, UK.
Posts: 442
Default Re: Zx81

Originally Posted by SiriusHardware View Post
Turning the transistor pinout into a practical layout, this is how to physically wire everything up. (See attached). I've laid it out so that the incoming +5V and the incoming video-in arrive from roughly the right place and direction.

When you cut the incoming video-in and +5V wires do it about 5-7mm inside the modulator housing, the transistor's base and collector leads can then be soldered directly to the ends of the incoming wires.

The resistor can be soldered between the transistor's emitter and the inside of the modulator case which is a handy 0V point - if you do that, do it low enough down the inside so the modulator lid can still be fitted on afterwards.
That sounds perfect! All neatly hidden away inside. Probably need to insulate the exposed pins too.
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