ive just finished repairing a commodore 1901 monitor i got here off macc.
it had loads of problems due to old age,but is now fully working with some extra features.
when i got this it had a bad mains switch that had fused contacts but that wasnt the end of this so i had to repair it.after the repair.
this had no colour on luma/chroma and was displaying black and white and needed a real overhaul as it had alot of problems switching between pal/rgb modes,so i thought i would service it and add a few nice features.
such as:
colour on composite
(i will document this later) its black and white normally...very interesting this one.
scart for rgb analogue input its digital rgb i normally as well on a 9 pin d sub as standard for the commodore 128 rgb output...
chroma luma repair with colour fix
interesting really, this monitor as its actually a thomson internally.
i will post a few pictures with various inputs being used to show the display quality and pictures of the front and rear,i will still have to fix the front flap as it has broken hinges...i'll do that at a later date as ive been very ill.
and a parts list of what i replaced and added to make this monitor really useful...
more later chaps...
here is a list of parts:
parts added:
1 toggle switch(was going to use a push to make latch switch but i havent got one )
1 scart socket
parts replaced:
1 mains switch(fused contacts monitor could not be turned on)
1 AN 5620 X (PAL)(on pal/rgb module) replaced to extend the life of the monitor)
2 BU508D's(tired components)
1 7812 regulator(as above)
1 TEA 2017(partly failed)
1 TDA 3506(replaced to extend life)
1 2K trimpot(i broke the original during the repair,doh)
removed one resistor grounding the chroma signal hence why it was black and white on luma chroma,cant remember the value.its on the back of the chroma port..didnt replace its not needed...
1 1.6 amp fuse due to corrosion.
i may also make a nice wiring loom for the tube neck assembly at a later date,original looks tired..
i'll upload pictures and descriptions later for anyone interested.no pictures of the actual repair that was a long night so didnt bother..