Composite Out

One of the things that have changed between the original ACE and these models is that there is no RF Out, the UM1233 was used to give access to analogue TV stopped being made some time ago and so it wasn't practicable to include one in the design.

 
Fortunately the input to the modulator was straight composite, so in theory it just need rerouting into the composite socket of  a modern TV and this is indeed the case but it needs a bit of amplifying
cation in order to work, so I have added the circuitry below, complete with a variable resistor to make sure it is not too bright.

It is basic 1 transistor amp and the transitor already used in the crystal circuit(Q1) the image seems very stable and sharp overall an improvement on the original image. I may do a similar amplification on the audio and output that for use via the monitor/TV speaker.

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