Philips G7000

From: Philip.Belben_at_powertech.co.uk <(Philip.Belben_at_powertech.co.uk)>
Date: Fri Aug 15 08:57:11 1997

> Assuming that there are no other connections to the 'Modulator' then one of
> those wires has to be a power rail. I'd guess (without seeing the device or

Oops! The connection to the PSU is another ground, so I guess you must
be right.

> the service manual) that the other 2 were luminance (Y) and (PAL-encoded)
> chrominance, or possibly composite colour video and audio if it feeds audio
> through to the TV.

If one is not composite video, where is the sync encoded? On Y (i.e.
making it composite mono)? I suppose this could just possibly be video
+ composite sync - just what I need.

> >> >> What chips _other than the 8048_ are in this device? Is the video side
> >> >> custom or does it use one of the many Philips video chipsets? (Philips
> >> >> Prestel terminals tend to be stuffed with their Teletext IC's, for
> >> >> example...)
>
> >Pretty boring, I'm afraid - 8245 and 6110 plus about 20 TTL chips. I
>
> What the heck are those?

8245 is a Nat Semi keyboard controller. This chip says Intel on it, but
I was assuming, probably very rashly, that it was the same thing.

6110 is a typo for 6810 :-), in fact Motorola MCM6810, a RAM chip.
Looking it up last night I discovered that it is in fact 128 by 8 (yes,
128 bytes!) so I cannot think what it is used for! (It is too slow to
be a video output buffer)

Philip.
Received on Fri Aug 15 1997 - 08:57:11 BST