Oh dear, oh dear, oh dear!

This was the first time I had got a power supply working with the Atom. I knew it was a bit ill but I am afraid this is all that happens no matter what you press.

With the assistance of the Atom Technical Manual, I stripped the machine down to its most basic configuration without any luck. I have had every IC out of the circuit board at some stage to try to isolate the fault.

The only way to stop it doing this is to remove either of IC 6 or IC 30 (both a 74LS138) in which case you just get a grey screen, or the 6847 video display generator (presumably a very close relative of the 6845 CRTC used in the Beeb) in which case you get nothing.

The curious thing is that this screen display even comes up with the 6502 out. How the machine can process anything like generating a screen display without a processor in it is beyond me.

By the way, this is the first appearance on BeebMaster of my lovely Fidelity Colour Television Monitor. I have had it since about 1983 or 1984, when I was a small boy, and it was my first ever television set. It has had a few repairs in its time but still works perfectly. At one point it died but was revived. When I had my Spectrum in the late 1980s I was switching between the Spectrum display and the aerial so often that the aerial socket came loose and fell inside the set. It is now clamped in place with a bolt.

The nice thing about this TV set is that Channel 8 is reserved for a SCART input. It must have been one of the first televisions with SCART.

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