How do I get colour on video out?

Acorn Application Note 1 gives the following information:

Modifications for the BBC Model B and B+
On Issue 1, 2 & 3 boards a 470 PicoFarad capacitor should be fitted between the emitter of Q9 (identifiedby an "e" next to one leg) and the central leg. On Issue 4 and later, the capacitor is on board and can be connected simply by fitting link 39 which may be found next to the modulator in the far right hand corner of the PCB. On the BBC Model B+ link S26 should be made.

Modifications for the Master 128
On Master 128 issue 1 boards a 470 PicoFarad capacitor should be connected between the east leg of R137 and the east leg of R153 which are located directly to the east of the modulator. Connections should be made on the component side of the PCB with the leads of the 470 PicoFarad capacitor being soldered directly to the leads of the two resistors. On Master 128 issue 2 boards link LK11 should be made.

This page last updated 11-Apr-2016